The Singapore Engineer November 2020

THE MAGAZINE OF THE INSTITUTION OF ENGINEERS, SINGAPORE

THE SINGAPORE ENGINEER

www.ies.org.sg

November 2020 | MCI (P) 004/03/2020

COVER STORY: PUB adopts smart tools to detect and preempt pipe leaks

PLUS

DIGITALISATION: Accelerating transformation of the built environment sector CIVIL & STRUCTURAL ENGINEERING: The use of Concrete Prefabricated Prefinished Volumetric Construction (PPVC) for Two Blocks of 40-Storey Residential Flats in Singapore PROJECT APPLICATION: Office complex planned entirely in 3D

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CONTENTS

www.ies.org.sg

FEATURES COVER STORY 10 PUB adopts smart tools to detect and preempt pipe leaks

New technologies help to minimise water loss from underground water pipes.

DIGITALISATION 14 Accelerating transformation of the built environment sector

A glimpse of some of the work being done in Helsinki, Finland.

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18 Winners of Year in Infrastructure 2020 Awards announced

A total of 14 Special Recognition awardees and 19 Award winners were honoured this year.

CIVIL & STRUCTURAL ENGINEERING 22 The use of concrete Prefabricated Prefinished Volumetric Construction (PPVC) for two blocks of 40-storey residential flats in Singapore The article outlines the pioneering application of a reinforced concrete (RC) composite shear wall system, utilising PPVC technology.

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PROJECT APPLICATION 32 Office complex planned entirely in 3D The project also uses digital solutions for formwork positioning and concrete monitoring.

35 Cold milling machines solve big challenge

They were used to precisely mill the spillway chute of the Oroville Dam, the highest dam in the US.

REGULAR SECTIONS 04 INDUSTRY NEWS 38 PRODUCTS & SOLUTIONS

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President Dr Richard Kwok Chief Editor T Bhaskaran t_b_n8@yahoo.com Publications Manager Desmond Teo desmond@iesnet.org.sg Publications Executive Queek Jiayu jiayu@iesnet.org.sg

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Editorial Panel Dr Chandra Segaran Prof Er Meng Joo Dr Ang Keng Been Mr Gary Chiam Dr Victor Sim Mr Syafiq Shahul Dr Alexander Wiegand Media Representative Multimedia Communications (2000) Pte Ltd sales@multimediacomms.sg

Design & layout by 2EZ Asia Pte Ltd Cover designed by Irin Kuah Cover images by PUB, Singapore’s National Water Agency Published by The Institution of Engineers, Singapore 70 Bukit Tinggi Road, Singapore 289758 Tel: 6469 5000 I Fax: 6467 1108 Printed in Singapore

The Singapore Engineer is published monthly by The Institution of Engineers, Singapore (IES). The publication is distributed free-of-charge to IES members and affiliates. Views expressed in this publication do not necessarily reflect those of the Editor or IES. All rights reserved. No part of this magazine shall be reproduced, mechanically or electronically, without the prior consent of IES. Whilst every care is taken to ensure accuracy of the content at press time, IES will not be liable for any discrepancies. Unsolicited contributions are welcome but their inclusion in the magazine is at the discretion of the Editor.

INDUSTRY NEWS

GOVERNMENT STATUTORY BOARDS AND AGENCIES

SENIOR MANAGEMENT CHANGES AT GOVERNMENT STATUTORY BOARDS AND AGENCIES

Mr Ng Lang

Mr Ngien Hoon Ping

Mr Simon Ong Hung Eng

Mr Ng Lang has been appointed Chief Executive of the Land Transport Authority (LTA). He has taken over from Mr Ngien Hoon Ping who has left the Administrative Service to join the FairPrice Group.

and the public transport operators have significantly improved rail reliability, from around 180,000 Mean Kilometres Between Failure (MKBF) in 2017 to over 1.6 million MKBF today.

Mr Ng was formerly the Chief Executive Officer of JTC Corporation (JTC).

He personally oversaw the system-wide upgrade of the North-South and East-West Lines, introduced the Rail Enterprise Asset Management System (REAMS), and built up local capability for rail testing. In doing so, he developed an ecosystem of supporting systems and capabilities that will help sustain high rail reliability.

Mr Tan Boon Khai, the former Chief Executive of Singapore Land Authority (SLA), has taken over as Chief Executive Officer of JTC, while Mr Simon Ong Hung Eng, Deputy Chief Executive of SLA, has been appointed as Acting Chief Executive of SLA.

Mr Ng Lang

Mr Ngien also led the delivery of several key infrastructure projects, such as Phase 1 of the ThomsonEast Coast Line, Mandai Depot and the new Lornie Highway. He helped to make active mobility safer and more sustainable, and introduced a new regulatory regime for a more competitive Point-to-Point Sector.

Mr Ng was appointed CEO of JTC on 1 September 2017. In this capacity, he oversaw the development of the nextgeneration industrial estates in Jurong Innovation District, Punggol Digital District and Woodlands North Coast.

The Land Transport Master Plan (LTMP) 2040 was also launched during his tenure, setting out the blueprint for a car-lite, well-connected, inclusive and sustainable land transport system that will meet Singapore’s future needs.

All the above senior management appointments took effect on 1 September 2020.

He also drove the rejuvenation plans for older industrial estates such as the development of Sungei Kadut Ecodistrict to support the transformation of manufacturing and anchor new growth industries such as in the agrifood technology sector.

Furthermore, he was credited with championing sustainability efforts across JTC’s industrial estates. This was accomplished through the implementation of a circular economy study on Jurong Island, greenery enhancement in JTC estates, and the introduction of large-scale SolarLand and SolarRoof programmes to reduce JTC’s carbon footprint. Within JTC, he also laid the groundwork to digitalise the way it works and transacts with customers.

Mr Ngien Hoon Ping Mr Ngien Hoon Ping was appointed Chief Executive of LTA on 12 November 2016. Under his leadership, LTA 04

Mr Tan Boon Khai

THE SINGAPORE ENGINEER November 2020

Mr Tan Boon Khai Mr Tan Boon Khai was appointed Chief Executive of SLA on 1 May 2015. In addition to strengthening SLA’s corporate governance structure, he also spearheaded a broad series of digitisation and digitalisation efforts to build a more integrated data-driven structure for SLA and its stakeholders, and drive innovation through better use of technology.

Together with GovTech, Mr Tan led SLA’s efforts to promote and enhance geospatial data and technologies for the public service and Singapore’s geospatial industry.

During his term, SLA received multiple awards and accolades for its service-centric and principal areas of work, including being ranked 1st in the Pro-Enterprise Panel (PEP) rankings in 2017, and also received key industry awards at various international geospatial forums.

Accelerating sustainable digitalisation of the built environment.

Finland is one of the most advanced countries in the world in adapting and developign digital tools to enhance the life-cycle of buildings – from design and construction to maintenance.

We at Helsinki Business Hub and KIRAHub have a long history in connecting companies in Singapore with Finnish technology and service providers in the digital built environment.

Learn more about the Singapore-Finland collaboration and opportunities for your company:

To grow your business, contact us and we will connect you with the right business partners as well as the relevant public sector decision makers in Finland.

Helsinki Busienss Hub is the international trade and investment promotion agency for the Finnish capital region. We help foreign companies to set up, grow and develop in Greater Helsinki, free of charge. Learn more: www.hbh.fi

KIRAHub is a non-profit association boosting sustainable digitalisation of the built environment in Finland.

Learn more: www.kirahub.org

INDUSTRY NEWS

PUB AWARDS DOMESTIC LIQUIDS MODULES CONTRACT FOR TUAS WRP PUB, Singapore’s National Water Agency, has appointed Sinohydro Corporation Limited (Singapore Branch) to construct the civil and structural components of Domestic Liquids Modules (DLMs) for the Tuas Water Reclamation Plant (WRP). The contract is valued at SGD 449.6 million.

Tuas WRP, a key component of PUB’s Deep Tunnel Sewerage System (DTSS) Phase 2 project, will be equipped to receive, for treatment, both domestic and industrial used water streams, from two separate deep tunnels. The plant’s two DLMs will house the various facilities, including biosorption tanks and membrane bioreactor systems, required to treat domestic used water, and will have a combined treatment capacity of 650,000 m3 per day which is the equivalent of about 245 Olympic-sized swimming pools of water. This treated water will undergo further purification to produce NEWater, while any excess will be sent for process needs or discharged into the sea.

Sinohydro’s bid for Tuas WRP’s DLMs contract was one of 14 that PUB received during an open tender exercise in November 2019. The contract encompasses civil & structural (C&S) works which were slated to commence in August 2020. Separate contracts will be called to equip the DLMs with mechanical & electrical (M&E) components. Construction work is expected to be completed by 2025.

It is the fourth major Tuas WRP construction contract awarded by PUB. The first was awarded in January 2019 to McConnell Dowell to carry out site development works.

Koh Brothers Building & Civil Engineering Contractor (Pte) Ltd and China Harbour (Singapore) Engineering Company Pte Ltd Joint Venture (JV) was appointed in July 2019 to build the Tuas WRP’s Influent Pumping Stations.

SembCorp Design and Construction had clinched the third contract for the plant’s biosolids treatment facility in March 2020.

Another seven construction tenders worth SGD 1 billion will be called before the end of 2021, including the plant’s Industrial Liquid Modules (ILMs) that will treat industrial used water.

Tuas WRP will have an initial treatment capacity of 800,000 m3 per day. The plant will be co-located with the National Environment Agency's (NEA) Integrated Waste Management Facility (IWMF) to collectively form Tuas Nexus which integrates solid waste and used water treatment processes to harness various synergies that will improve overall plant performance and optimise land use.

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The DTSS Phase 2 is a SGD 6.5 billion infrastructure project that will enhance Singapore's water sustainability by boosting PUB’s capability to reclaim and recycle water in an endless cycle. Upon completion in 2025, DTSS Phase 2 will convey used water from the western part of Singapore to Tuas WRP for treatment. DTSS Phase 1, which covers eastern Singapore and channels used water to Changi WRP, was completed in 2008.

AURECON LEADERS APPOINTED TO FIDIC COMMITTEE

Ms Tracey Ryan

Ms Stéphanie Groen

Two leaders from international engineering, design and advisory company Aurecon have been appointed to the International Federation of Consulting Engineers (FIDIC) Sustainable Development Committee to advise the engineering consulting industry on sustainability issues and on how to make a positive contribution towards combatting climate change.

Aurecon’s Managing Director for New Zealand, Tracey Ryan, has been named as Chair of the 11-strong international committee, while Stéphanie Groen, Aurecon’s Director of Coastal & Climate Change in Asia joins as a committee member.

The new committee will advocate, guide and monitor best practice in sustainable development across the global engineering and construction industry. In addition to publishing tools and guides to support best practice, the committee will advise the FIDIC board on all aspects of sustainable development as part of the organisation’s commitment to helping the industry achieve the UN’s Sustainable Development Goals.

INDUSTRY NEWS

MAJOR ROLE FOR BLACK & VEATCH

IN UK WATER PROJECT Black & Veatch has extended its AMP7 role with Thames Water after being appointed by main contractor Galliford Try as its Strategic Engineering Design Partner for two framework lots in London, UK. As engineering design partner to Galliford Try, Black & Veatch will be supplying engineering services on Lot 3 and Lot 6. The former covers non-infrastructure projects (water and wastewater treatment) across London, while the latter encompasses infrastructure projects (water and waste water carriage) in south London.

Lot 3 and Lot 6 programmes will focus almost exclusively on capital enhancement and capital maintenance upgrades of existing assets. The work will provide additional resilience for water supplies and protect the enviroment for communities throughout London.

“Black & Veatch and Galliford Try have a strong collaborative relationship, working together as GTBV joint venture for the Southern Water non-infrastructure programme in AMP7, GBV joint venture on Environment Agency frameworks and as part of the ESD joint venture for Scottish Water”, said Mr Scott Aitken, Executive Managing Director of Black & Veatch Europe.

Black & Veatch’s digital water solutions will be central to helping create assets which will support Thames’ investment, sustainability and customer service goals.

These include intelligent process and instrumentation diagrams (iP&IDs); 3D and 4D engineering, planning and virtual visualisation tools; and the ECO-X cloudbased digital ecosystem. iP&IDs are the first steps in the creation of a single source of engineering metadata.

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INDUSTRY NEWS

LEADERS FROM THE BUILT ENVIRONMENT SECTOR RECOGNISED

AS iBUILDSG DISTINGUISHED FELLOWS Six outstanding Built Environment sector leaders, whose professions straddle academics, architecture, contracting, engineering and real estate development, have been conferred the title of iBuildSG Distinguished Fellow. This is the first year that the iBuildSG Distinguished Fellow has been awarded. The Distinguished Fellows (in alphabetical order) are:

Mr Chia Ngiang Hong

Dr Ho Nyok Yong

Professor Lam Khee Poh

Ar Rita S L Soh

Mr Wong Heang Fine

• Mr Chia Ngiang Hong, Group General Manager, City Developments Limited (CDL).

• Dr Ho Nyok Yong, Chief Operating Officer cum Executive Director, Samwoh Corporation Pte Ltd. • Professor Lam Khee Poh, Provost’s Chair Er. Lee Chuan Seng Professor of Architecture and Building, and Dean, School of Design and Environment, National University of Singapore; and Emeritus Professor of Architecture, Carnegie Mellon University.

• Er. Lee Chuan Seng, Emeritus Chairman, Beca Asia Holdings Pte Ltd. • Ar Rita S L Soh, Managing Director, RDC Architects Pte Ltd. • Mr Wong Heang Fine, Group Chief Executive Officer, Surbana Jurong Pte Ltd. The iBuildSG Distinguished Fellow title recognises the exemplary contributions made by these individuals to the Built Environment sector. They were selected based on their active leadership in their professional community, commitment towards the key industry transformation areas of Green Buildings, Design for Manufacturing and Assembly (DfMA) and Integrated Digital Delivery (IDD), as well as recognition of their contributions on both the local and international stages.

The Distinguished Fellows will serve as inspiration and role models for BE professionals, especially in their roles as champions for industry transformation, lending their expertise through forums, panel discussions and as subject matter experts for the industry.

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Younger professionals can look forward to their mentorship. The first group of Distinguished Fellows will also be invited to sit on the panel for selecting for future iBuildSG Distinguished Fellows and play a unique role in peer reviews.

This year’s selection panel was made up of the Chief Executive Officers from the Building and Construction Authority (BCA), Housing & Development Board (HDB) and JTC Corporation. Moving forward, the panel members will include CEOs of BCA and JTC, and three Distinguished Fellows.

Mr Hugh Lim, CEO, BCA, said “On behalf of the selection panel and the industry, I would like to extend my congratulations to our inaugural iBuildSG Distinguished Fellows. Throughout their illustrious careers, they have contributed significantly in shaping the Built Environment to what it is today. As industry leaders, every one of them has spearheaded efforts to bring about change and achieve a forward-looking and progressive Built Environment sector, both locally and in overseas markets. I look forward to their continued contributions to the sector, as they impart their experience, knowledge and know-how to the younger generation of Built Environment professionals”.

INDUSTRY NEWS

The iBuildSG LEAD Framework and Conferment of Distinguished Fellows The conferment of the iBuildSG Distinguished Fellow title is the highest level of recognition under the iBuildSG Leadership Engagement and Development (LEAD) Framework which was launched in 2019, in partnership with the industry.

The iBuildSG LEAD framework is organised along five strategic thrusts, with each thrust offering benefits to firms and individuals. The five strategic thrusts are: Long-term, Engage, Align, DEvelop, Recognise (LEADER).

The objective of the LEAD Framework is to advance and recognise a core group of committed and experienced industry leaders to lead and drive sustained transformation of the Built Environment (BE) sector.

Under the framework, there are four levels of leadership that have been identified, cutting across the BE value chain: • Distinguished Leaders: These are leaders who are recognised for having made significant lifetime contributions to the Singapore BE sector, achieving local or international recognition for their contributions.

Distinguished leaders are characterised by their distinctive track record, the commitment that they have demonstrated to advance the sector, as well as their ability to lead their peers, both at home and abroad.

These leaders will be recognised as ‘iBuildSG Distinguished Fellows’(which is a lifetime conferment) under the LEAD framework.

• Senior Leaders: These are leaders in senior management positions in their respective firms, with strong professional recognition and track record. It is hoped that they will be committed to transforming the sector and are able to take on key leadership roles in Trade Associations and Chambers (TACs) or industry committees. Senior Leaders who demonstrate strong leadership roles in TACs as well as serve as active contributors to the transformation of the industry will be appointed as ‘iBuildSG Fellows’ under the LEAD framework. The appointment is for a term and is subject to renewal after each term.

• Young Leaders: This group consists of firm-nominated young leaders aged 35 and below, who demonstrate good business acumen and leadership potential. The LEAD framework will help to develop them as leaders in the BE sector, who can also contribute more actively to TACs or industry committees.

• Future Leaders: Future Leaders comprise the iBuildSG Scholarship and Sponsorship recipients. The intention is to groom them so that they will demonstrate commitment to a BE career, with a passion for innovation and digitalisation, and are committed to professional development and participation in TAC and industry events.

Collectively and jointly with accredited technical professionals, these leaders will form a cohesive core

and will be key drivers for the industry to advance internationalisation, drive collaboration and inculcate an industry-wide culture that embraces innovation and digitalisation.

PROJECTED CONSTRUCTION DEMAND FOR 2020 REVISED BCA has revised its projected construction demand for 2020 from the earlier forecast of SGD 28 billion - SGD 33 billion released in January 2020 to SGD 18 billion - SGD 23 billion. This comes after BCA’s mid-year review of construction contracts awarded in 1H2020, and upcoming public and private sector projects expected for the rest of the year.

The downward revision is due to a drop in private sector construction demand, and postponements in the award of some public sector projects from 2020 to 2021, as contractors and suppliers have asked for more time to assess the impact of COVID-19 on resource management and project implementation timelines.

Year

Construction demand (Value of contracts awarded, in SGD billion)

Public

Private

Total

2019

19.03

14.5

33.53

2020 (forecast)

11 – 14

7-9

18 - 23

Comparison of Construction demand in 2019 with that forecast for 2020

Construction demand is expected to recover to some extent from 2021. This will be supported by public residential developments and upgrading works, developments at the Jurong Lake District, construction of new healthcare facilities and various infrastructure projects such as the construction of the Cross Island MRT Line. It is important that the construction industry remains vigilant to prevent a resurgence of COVID-19 cases, which could bring the sector to a halt again. BCA will provide an update on the projected construction demand for 2021 and 2022 in early 2021.

BCA will continue to lean forward to provide assistance to the construction industry in various ways, including financial assistance to help firms tide through this very challenging period brought about by COVID-19.

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COVER STORY

PUB ADOPTS SMART TOOLS

TO DETECT AND PREEMPT PIPE LEAKS New technologies help to minimise water loss from underground water pipes.

Precious water can be lost through leaks and cracks in aged pipes over time and it is extremely difficult to locate such ‘hidden’ leaks until water reaches the ground surface or shoots up due to the pressure in pipes.

By turning to smart tools and new technologies such as leak monitoring sensors, inline pipe inspection tools and smartphone sensors, PUB, Singapore’s National Water Agency, seeks to enhance its leak detection capabilities to reduce water loss.

A network of 5,700 km of water pipelines conveys clean potable water to 1.6 million customers, island-wide. PUB has, in place, a comprehensive pipe maintenance and renewal programme, to ensure the water pipes and fittings are always in good working condition. Through regular inspection and replacement of old and leak-prone pipes, PUB now records 5 leaks per 100 km of pipes per year, which is about the lowest incidence of leaks in the world.

In 2014, PUB recorded 10 leaks per 100 km of pipes.

As most pipes are underground, small leaks often go unnoticed and eventually develop into bigger leaks. With the use of acoustic sensors and innovative technologies, PUB has been able to locate and repair developing leaks before a pipe burst occurs. This will reduce water service disruption to customers, as a badly leaking pipe would need to be shut-off for repairs.

Smart tools for more accurate and effective leak detection

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Leak monitoring sensor

Leak monitoring sensors were first trialled in 2017, with 120 sensors installed along approximately 70 km of large water mains, for early detection of developing leaks.

These sensors work by monitoring and analysing noise characteristics in pipes, to determine the presence of leaks. The data is collated in a centralised server, and advanced analytics are used to interpret readings and alert PUB automatically when a leak is identified. The sensors can accurately identify a leak along the pipe and determine its location within 3 m of the leak.

PUB is also exploring the use of inline pipe inspection tools for leak detection in large water mains. The tool is inserted directly into the pipe, which allows for more targeted and precise inspection of the pipe wall, to detect any cracks or anomalies. Propelled by the flow of water in the pipe, these tools can easily survey long stretches of a pipe in a single deployment. One such tool is a ballshaped sensor that can determine the leak location to an accuracy of 2 m, by picking up acoustic or noise signature related to the leaks. PUB will be deploying these sensors to survey 500 km of pipes over the next five years.

The trial was successful, with the sensors detecting 13 leaks over a three-year period. In one incident, in 2018, the sensors alerted PUB to a potential leak on a 700 mm diameter water pipe alongside a major expressway. Upon excavation, a 13 mm hole was discovered at the bottom of the pipe, within 0.5 m of the location reported by the sensors. The hole was created due to corrosion. This early detection allowed PUB to promptly repair the pipe and prevent further water loss.

Following on from the trial, PUB plans to progressively scale up the number of sensors in the network and deploy 1,200 sensors for leak monitoring, islandwide, by 2021.

For smaller water pipes, the PUB leak detection teams were recently equipped with smartphone sensors, a portable and easy-to-use survey tool that has proven to be effective in locating leaks. The sensor, connected to a smartphone, is placed on pipe fittings such as hydrants and valves to pick up sounds from the pipe. The smartphone automatically digitalises and analyses the acoustic signal in real-time via a dedicated mobile application to check for leaks. Two sensors can be deployed on separate pipe fittings at once, to correlate their readings and determine the leak location within 2 m along the pipe.

THE SINGAPORE ENGINEER November 2020

COVER STORY

Listening stick

Inline pipe inspection tool

Noise logger and correlator

Smartphone sensor

Mr Ridzuan Ismail, PUB’s Director of Water Supply (Network) said, “PUB is always on the lookout for new technologies for early leak detection, so that we can minimise water loss in the network and increase the resilience of service that we provide to our customers.

With intelligent leak monitoring and detection technology, we are taking a more preventive and predictive approach and moving away from a resource-intensive operation that requires very specialised skills. This will bring us closer to our goal of transforming our operations through digitalisation, to become a smart utility of the future”.

Evolution of leak detection methods over the years In the early days of leak detection, operators and engineers listened for noise generated by water escaping, under pressure, from buried pipes. In the 1970s, mechanical tools such as listening sticks were used to locate pipe leaks. They had limited accuracy as they relied on the hearing and experience of the engineer. There could also be interference from ambient noises in the environment, such as from passing vehicles. Nonetheless, listening sticks are highly portable and particularly useful to confirm the precise location of the leak on site, prior to ground excavation to reach the pipe.

Correlation graph showing leak detected in water pipe

In the early 2000s, PUB started deploying noise loggers and correlators for more dynamic leak detection. Deployed during the night, the noise loggers would be used to inspect large areas of the pipe network and localise the leak to within a 100 m stretch of pipe. Thereafter, the correlators were used to determine the actual leak location on the pipe. Listening sticks, as well as noise loggers and correlators, are still in use today to complement the suite of tools for effective leak monitoring and detection.

Public feedback Public feedback is also an important channel that PUB taps on for leak detection. PUB’s call centre operates 24 hours a day.

All images by PUB, Singapore's National Water Agency THE SINGAPORE ENGINEER November 2020

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COVER STORY

Infographic on detecting leaks in water pipelines 12

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COVER STORY

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DIGITALISATION

ACCELERATING TRANSFORMATION OF

THE BUILT ENVIRONMENT SECTOR Helsinki, the capital of Finland, and Singapore are considered to be two smartest cities in the world.

‘The Singapore Engineer’ obtains a glimpse of some of the work being done in Helsinki, Finland, and the possibilities for collaboration with Singapore, from Ms Irma Ylikangas, Senior Business Advisor, Helsinki Business Hub, and Mr Teemu Lehtinen, CEO, KIRAHub.

Facilitating strategic parnerships ‘The Singapore Engineer’: Could you provide an introductory description of Helsinki Business Hub? Irma Ylikangas: Established in 2006, Helsinki Business Hub (HBH) is the international trade and investment promotion agency for the capital region of Finland.

As a non-profit organisation, its services are free-ofcharge.

TSE: What is the role of HBH and what are some of its achievements?

IY: HBH helps foreign companies to set up their business, grow and develop in Greater Helsinki which offers key business opportunities in (but not limited to) the following fields: • Information and communications technology.

• Health: personalised health & med tech.

• Smart & clean solutions, especially related to the built environment and sustainability, e.g. smart buildings, smart mobility, smart energy and the circular economy.

• Hotel investments.

HBH helps companies throughout their journey to Finland and the Greater Helsinki area - from the initial consideration to establishing and expanding their business. Its services include, for example, helping to find the best location for a business, matchmaking and finding co-operation opportunities with Finnish companies and research institutes, and finding deal flow from Finland or opportunities for expansion in Greater Helsinki.

HBH can also help organisations looking for specific technological solutions or strategic partnerships including in R&D. In 2019, HBH helped foreign companies to create almost 370 jobs, invest about EUR 78 million and kick-start almost 17 business deals in the Greater Helsinki region. Out of these 17 deals, six were with Singaporean organisations operating in the built environment sector. Solutions around robotics, automation, intelligent data and IoT or data management to improve indoor air quality have been especially successful.

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Ms Irma Ylikangas, Senior Business Advisor, Helsinki Business Hub. Image: Petri Mast.

TSE: Could you provide more information on the cooperation between Finland and Singapore?

IY: Helsinki has a long history of close co-operation with Singapore, and since 2017, there has been a special focus on the built environment and smart city topics.

Sharing information about new and innovative digital tools to increase information flow and efficiency of the construction process, has been our goal.

The digitalisation of the construction industry has been one area which the Finnish government has been supporting, to enable new innovations.

HBH has organised several business delegations to Singapore to match innovative Finnish companies with Singaporean organisations. KIRAHub has been a partner in these delegations.

HBH is cooperating with multiple leading organisations in Singapore, such as IPI Singapore, Building and Construction Authority (BCA), Enterprise Singapore (ESG) and Housing & Development Board (HDB).

Recently, HBH also started to cooperate with the Smart Urban Co-Innovation Lab which is Southeast Asia’s first industry-led lab for smart cities solutions development.

The Smart Urban Co-Innovation Lab has been initiated

by CapitaLand and is supported by the Infocomm Media Development Authority (IMDA) and Enterprise Singapore (ESG). It is operated by AIRmaker.

More information may be obtained from www.hbh.fi

DIGITALISATION

Innovation hub for sustainable digitalisation ‘The Singapore Engineer’: Could you provide a brief description of KIRAHub and its functions and objectives?

Teemu Lehtinen: KIRAHub is a non-profit association and an innovation hub for boosting sustainable digitalisation of the built environment sector. It was founded in 2018 to continue the work that started in the governmental KIRA-digi project (2016-2019). We work closely together with government, municipalities, private sector, research institutions and international networks, to build an open ecosystem for digital transformation.

Our aim is to achieve the following: • Create transparent ecosystems.

• Connect the right people and organisations.

• Promote the adoption of new solutions and flow of data.

KIRAHub’s vision is to make Finland a pioneer in the digitalisation of the sustainable built environment - one that can be a global benchmark for successful implementation of infrastructure for balanced and future-oriented lifestyles.

TSE: What is KIRA-digi? What is its scope?

TL: KIRA-digi is a project aimed at boosting digital transformation within the real estate and construction sector in Finland. The project was intended to act as a wake-up call for the sector which has been slow to take advantage of the digital route, in order to achieve productivity improvements through ICT, as other sectors have done.

The main objective was to get as many companies and stakeholders as possible, to experiment with new digital solutions within their processes and services. KIRAdigi was a joint effort involving the public and private sectors, that promoted digital experimentation, with 40% of government funding. A total of 139 experimental projects, worth almost EUR 13 million were started during 2017-2018, covering the whole lifecycle of the built environment - from land use planning and zoning, all the way to the project level which includes design, construction, operation and maintenance of the built assets.

The project also promoted better information flow with open data and APIs and analysed the needs for legislative changes, in order to achieve true platform economies within the built environment. There were follow-up initiatives, starting with the reform of the land use and building act, and the national data platform RYHTI. TSE: Could you briefly touch on the KIRA-digi experiments in digital land use planning, wind simulations with a city model, automating design processes, and BIM-based building permits?

TL: The digital land use planning project experimented with a digital platform for land use planning and zoning,

Mr Teemu Lehtinen, CEO, KIRAHub, Helsinki, Finland.

Image: Mina Nytorp.

that integrates data from different sources and visualises it for stakeholders. The platform also had a real-time chat function. The objectives were to make the land use planning process faster, to reduce waiting times and to accelerate the shared understanding and decisionmaking.

Coming to wind simulations, these are necessary, especially when planning areas for efficient construction close to the sea. Large constructed units and high-rise buildings can increase the negative effects of wind in the city. The wind has a significant impact on the micro climate, comfort and safety of the streets and pedestrian areas. 3D virtual models make it possible to study the effects of the wind in the current scenario and in the future. The wind in the city can be explored with techniques such as computational fluid dynamics.

Implementing wind simulations, at the earliest possible stage of planning, provides a good basis for planning a comfortable and safe urban environment. The simulations involved calculations using the ANSYS Discovery Live application which has been used in product development, in the German automotive industry, for example, for designing cars and exploring air flows.

In this pilot project, the application was tested, for the very first time, for modelling and analysing airflow behaviour, using information from a city model. The application produced very accurate results regarding information on both large and small areas. It would also be possible to model the wind and air pressure conditions, for example, on a single street.

Regarding the automation of design processes, it must be said that the construction process, with its many parties and numerous execution alternatives, is very difficult to manage as a whole. There are not enough resources for performing the calculations for different alternatives, with the selection often falling on the solution that has been used the longest. With machine learning methods, alternative solutions could be generated with computer programs.

Modelling a building’s details, according to an image, is a significant part of design, so even a partial boost to efficiency in this work could be immediately applied in practice. The main objective of the project was to THE SINGAPORE ENGINEER November 2020

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DIGITALISATION

find out how BIM data models of buildings could be applied as starting data for machine learning and what the requirements are for their application in building design. Various AI methods are applied for analysing the material, and tests are conducted to determine whether a proposal for a design solution can be generated on the basis of this material. The subject of a test can be, for instance, the creation of a detail for a joint in a single building.

The project on BIM-based building permits was a joint effort by three different municipalities (Vantaa, Järvenpää and Hyvinkää) and four different suppliers (Evolta, Gravicon, Solibri and Sova3D). The project sought to answer how well the targets set in the project description document would be met, and how the process should be changed or how the various software applications and their interoperability should be developed in the future. The project assessed the viability of the process, from the perspective of the authorities, applicants for permits, and designers.

More and more sites are designed in a model-based way but, for the processing of the permit, the 3D designs are still saved in the traditional 2D format.

This process results in extra work for both designers and building controllers. In future, the majority of buildings will be designed using data models, and their compliance with building regulations will be checked electronically, using artificial intelligence, by the designer, before the application for a building permit is submitted. The authorities’ task concerning the processing of permits will focus on examining the application from the perspective of the cityscape and the local plan and, on a case-by-case basis, approving justified deviations. Permits will be processed in a few weeks or days, instead of months.

KIRA-digi experiment: ‘The paperless construction site’.

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THE SINGAPORE ENGINEER November 2020

TSE: Could you elaborate on two KIRA-digi experiments - ‘The paperless construction site’ and ‘Managing concrete curing conditions with IoT on site’?

TL: The project on ‘The paperless construction site’ experimented with real-time transfer of information to people working on a construction site through augmented reality. The aim was to efficiently provide workers with information that was essential for their work stages and roles during the construction process.

The project conducted an experiment in which the workers in a construction project received crucial information, in real-time, for performing their tasks on the construction site, using augmented reality.

The information was provided in a digital and easy-tounderstand format and it was shared with the workers at the right time and location. The project also measured the impact of the information on productivity. The project was divided into the following stages: • Generation of a digital 2D work image of the key work stages for each worker.

• Extraction of relevant design information, required by each worker, from the data model, in the form of 3D images. Digital transfer of the information, in 3D, to a tablet or smartphone.

• Combination of the 3D images based on the data model with augmented reality, i.e. video images of the site, on the tablet.

• Enrichment of the information with 3D data that is crucial for the installation and, in combination with augmented reality, communication of the information to the right location.

The experiment was limited to a residential flat and a bathroom undergoing plumbing renovation which

DIGITALISATION

was carried out by Fira, a construction company. The experiment was carried out as a collaboration between Fira, and Sweco, an architecture and engineering consultancy. The augmented reality and location-based service were provided by the VTT Technical Research Centre of Finland.

Several key learning points emerged from the project.

• The feedback indicated a desire for better measuring accuracy and more specific measuring information directly from the screen.

• The experiment showed how challenging it is to execute a practical BIM on a small mobile screen.

• Users should be able to add feedback to the BIM, on the go, so there is a need for applications that enable two-way information transfer.

• At this stage, the BIM itself does not yet contain all the measurements that need to be shown to the user.

The project on ‘Managing concrete curing conditions with IoT on site’ developed a smart method for ensuring that concrete cures within the allotted time at the construction site. The timely drying of concrete on construction sites is important not only from a cost perspective, but also for avoiding structural damage due to dampness. Also, construction work, such as the the laying of carpets cannot proceed until the concrete dries.

At the same time, the project was able to map structures at risk and the progress in the curing of concrete placements.

A secondary objective was to assess the functioning of wireless data transfer methods (e.g. Wirepas, Lora and Sigfox) in a construction site environment. The project connected IoT (Internet of Things) solutions to dampness management systems used during construction. The IoT network included physical devices and machinery, such as air humidity and temperature sensors, that were

connected to the Internet. The project was carried out in a residential building under construction. Air humidity and temperature sensors were installed in the rooms to be monitored, and the measurement data generated by the sensors was transferred wirelessly to a cloud service.

Dampness in the drying concrete was measured at critical points. When the conditions were not optimal for the drying process, the system being developed alerted the site management to take action. The measurement data was analysed using machine learning methods. The aim was to find a way to improve the predictability of the drying process. The data collected in this project can also be utilised when planning the execution of future projects.

TSE: How can Finland and Singapore collaborate to further the digitalisation of the built environment industry?

TL: We started a close collaboration with Singapore during the KIRA-digi project and it has been really fruitful. There were delegations from both countries travelling back and forth to learn about solutions and implementation of digital processes. Both Finland and Singapore have a high ‘maturity level’ in the understanding of the possibilities in the digitalisation of the built environment and smart cities solutions.

Therefore, it makes sense to keep learning from each other. Going forward, I see a lot of potential for connecting different data platforms, and accessing data in a unified way on a global level, to be used in AI and machine learning solutions and digital tools for the built environment. Finland and Singapore could lead the way in this, globally, and I am really looking forward to a deepening of the collaboration on different levels between the governments, innovation hubs, companies and data platforms.

More information may be obtained from www.kirahub.org

KIRA-digi experiment: ‘Managing concrete curing conditions with IoT on site’.

THE SINGAPORE ENGINEER November 2020

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WINNERS OF YEAR IN INFRASTRUCTURE 2020 AWARDS ANNOUNCED A total of 14 Special Recognition awardees and 19 Year in Infrastructure 2020 Award winners were honoured this year.

Bentley Systems Incorporated, a leading infrastructure engineering software company, announced the names of the Year in Infrastructure 2020 Award winners and Special Recognition Awardees, on 21 October 2020, during the Year in Infrastructure 2020 Conference, held virtually for the first time.

The annual awards program honours the work of Bentley users in advancing design, construction, and operation of infrastructure throughout the world.

Sixteen independent jury panels selected 57 finalists from over 400 nominations submitted by more than 330 organisations from more than 60 countries.

WINNERS OF YEAR IN INFRASTRUCTURE 2020 SPECIAL RECOGNITION AWARDS Category: Advancing Project and Asset Longevity Winner: HDR Project: Marc Basnight Bridge Location: Dare County, North Carolina, United States –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Bridge Asset Performance Modeling Winner: Ulsan National Institute of Science and Technology (UNIST) Project: A Smartwatch on the Bridge Location: Ulsan, Ulju-gun, South Korea –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Industrial Asset Performance Modeling Winner: The Institute of Engineering and Ocean Technology / Oil and Natural Gas Corporation Limited Project: Challenges in Addressing Life Extension of Ageing Platforms in Western Offshore of India Location: Mumbai, India –––––––––––––––––––––––––––––––––––––––––––––– Category: Comprehensiveness in Industrial Digital Twins

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Category: Comprehensiveness in Transportation Digital Twins Winner: PT WASKITA Karya (Persero) Tbk Project: Railway Facility for Manggarai to Jatinegara: Package A - Phase II (Main Line II) Location: South Jakarta, Jakarta, Indonesia –––––––––––––––––––––––––––––––––––––––––––––– Category: Comprehensiveness in Urban Digital Twins Winner: JSTI Group Co Ltd Project: Hengjiang Avenue Rapid Transformation Project Location: Nanjing, Jiangsu, China –––––––––––––––––––––––––––––––––––––––––––––– Category: Comprehensiveness in a Connected Data Environment Winner: Roads & Transport Authority (RTA) Project: Collaborative Information System Implementation - Whole Lifecycle Common Data Environment Location: Dubai, United Arab Emirates –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Virtualization through Digital Twins Winner: Network Rail Project: Overcoming Challenges Under COVID-19 Lockdown Location: Wales and Western Region, United Kingdom –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Model-based Delivery through Digital Twins Winner: NYS Department of Transportation Project: Model Based Contracting - NYS RT 28 over the Esopus Location: Mount Tremper, New York, United States –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Mixed-Reality Workflows

Winner: Volgogradnefteproekt LLC

Winner: Liaoning Water Conservancy and Hydropower Survey and Design Research Institute Co Ltd

Project: Ethane-Containing Gas Processing Complex Construction Support

Project: Chaoyang Underground Pumping Station Project of the LXB Water Supply Project Phase II

Location: Ust-Luga, St Petersburg, Russia

Location: Chaoyang, Liaoning, China

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DIGITALISATION

Category: Advancing Sustainability Digital Twins Winner: Shanghai Institute of Mechanical and Electrical Engineering Co Ltd Project: Shanghai Electric Environmental Protection Group Technology Renovation and Expansion Project for Nantong Thermoelectric Waste Incineration

Category: Digital Cities Winner: City of Helsinki Project: Digital City of Synergy Location: Helsinki, Finland

Location: Nantong, Jiangsu, China

Category: Geotechnical Engineering Winner: Golder Associates Hong Kong Ltd Project: Tuen Mun-Chek Lap Kok Link Tunnel, Southern Landfall Location: Hong Kong

–––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Sustainable Architecture Winner: Swatch Ltd, Shigeru Ban, Itten+Brechbühl AG Project: Swatch Headquarters Location: Biel, Bern, Switzerland –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Sustainable Energy Winner: Guangdong Hydropower Planning & Design Institute Project: Guangdong Yangjiang Pumped Storage Power Station Location: Yangjiang, Guangdong, China –––––––––––––––––––––––––––––––––––––––––––––– Category: Advancing Sustainable Water Winner: Jacobs Project: San Jose Headworks Location: San Jose, California, United States ––––––––––––––––––––––––––––––––––––––––––––––

WINNERS OF YEAR IN INFRASTRUCTURE 2020 AWARDS Category: 4D Digital Construction Winner: DPR Construction Project: 2019 LSM DS Tech Upgrade Location: Durham, North Carolina, United States –––––––––––––––––––––––––––––––––––––––––––––– Category: Bridges Winner: Chongqing Communications Planning, Survey & Design Institute Co Ltd Guizhou Communications Construction Group Co Ltd Guizhou Bridge Construction Group Co Ltd Project: Digital Design and Construction of Taihong Yangtze River Bridge Location: Chongqing, China

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–––––––––––––––––––––––––––––––––––––––––––––– Category: Land and Site Development Winner: AAEngineering Group Project: Dzhamgyr Mine - Project Implementation in Extreme Conditions Location: Talas Region, Kyrgyzstan –––––––––––––––––––––––––––––––––––––––––––––– Category: Manufacturing Winner: MCC Capital Engineering & Research Incorporation Ltd Project: BIM Technology-Based Construction of Digital Plant for Iron & Steel Base in Lingang, Laoting of HBIS Group Co Ltd Location: Tangshan, Hebei, China –––––––––––––––––––––––––––––––––––––––––––––– Category: Mining and Offshore Engineering Winner: AAEngineering Group Project: Digital Twin of AKSU Plant: From Concept to Startup Location: Aksu, Akmola Region, Kazakhstan –––––––––––––––––––––––––––––––––––––––––––––– Category: Power Generation Winner: Shanghai Institute of Mechanical and Electrical Engineering Co Ltd Project: Shanghai Electric Environmental Protection Group Technology Renovation and Expansion Project for Nantong Thermoelectric Waste Incineration Location: Nantong, Jiangsu, China –––––––––––––––––––––––––––––––––––––––––––––– Category: Project Delivery Winner: Sweco Project: Sweco | Digitalisation with BIM Location: United Kingdom

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Category: Buildings and Campuses Winner: Voyants Solutions Private Limited Project: Bangladesh Regional Waterway Transport Project 1 – Shasanghat (New Dhaka) IWT Terminal Location: Dhaka-Shasanghat, Narayanganj, Chandpur, and Barisal, Bangladesh

Category: Rail and Transit Winner: POWERCHINA Huadong Engineering Corporation Limited Project: Innovative Application of Digital Engineering Technology in Shaoxing Rail and Transit Construction Location: Shaoxing, Zhejiang, China

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–––––––––––––––––––––––––––––––––––––––––––––– THE SINGAPORE ENGINEER November 2020

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Category: Reality Modeling Winner: Khatib & Alami Project: Geo-enabling Reality Model Tips and Tricks Location: Muscat, Oman

Category: Utilities and Communications Winner: Sterlite Power Transmission Limited Project: Sterlite BIM Location: Tripura, India

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Category: Road and Rail Asset Performance Winner: Roads and Transport Authority (RTA) Project: Collaborative Information System Implementation - Whole Lifecycle Common Data Environment Location: Dubai, United Arab Emirates

Category: Utilities and Industrial Asset Performance Winner: Shell’s QGC business Project: Evolution of Engineering Data, Documents and Information Management Location: Brisbane, Queensland, Australia

–––––––––––––––––––––––––––––––––––––––––––––– Category: Roads and Highways Winner: Sichuan Road & Bridge (Group) Co Ltd Project: BIM Technology Application on Chengdu-Yibin Expressway Location: Chengdu, Sichuan, China ––––––––––––––––––––––––––––––––––––––––––––––

–––––––––––––––––––––––––––––––––––––––––––––– Category: Water and Wastewater Treatment Plants Winner: Hatch Project: Ashbridges Bay Treatment Plant Outfall Location: Toronto, Ontario, Canada ––––––––––––––––––––––––––––––––––––––––––––––

Category: Structural Engineering Winner: WSP Project: WSP Overcomes Complex Challenges with Bentley’s Technology to Deliver Principal Tower Location: London, England, United Kingdom

Category: Water, Wastewater, and Stormwater Networks Winner: DTK Hydronet Solutions Project: Digital Water Network Engineering & Asset Management of Dibrugarh Water Supply Project Location: Dibrugarh, Assam, India

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Year in Infrastructure 2020 Awards Trophy and Yearbook: Detailed descriptions of all nominated projects are in the print and digital versions of Bentley’s 2020 Infrastructure Yearbook, which will be published in early 2021.

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LE QUEST (15 STY)

THE CLEMENT CANOPY(40 STY)

PARK COLONIAL (14/15 STY) Park Colonial (14/15 STY)

28 Sin Ming Lane #04-136 Midview City, Singapore 573972 Tel: +65 6291 6292 Fax: +65 6293 2196 Website: www.tw-asia.com

TW-ASIA Consultants Pte Ltd

COMPOSITE STRUCTURAL WALL AND METHOD OF CONSTUCTION THEREOF  SINGAPORE PATENT NUMBER 10201703972W  EUROPE PATENT NUMBER 3263795

AVENUE SOUTH RESIDENCE (56 STY)

Consulting Engineers Civil Structural

CIVIL & STRUCTURAL ENGINEERING

THE USE OF CONCRETE PREFABRICATED PREFINISHED VOLUMETRIC CONSTRUCTION (PPVC) FOR TWO BLOCKS OF 40-STOREY RESIDENTIAL FLATS IN SINGAPORE

by Wong Seng1, Heng Kim Huat1, Maey Leow Geok Mui1, Dr Tan Teng Hooi2, Chew Keat Chuan3, and Tan Chong Lin3 In line with the initiative of Singapore’s Building and Construction Authority (BCA) to promote productivity in the construction industry using PPVC technology, this article outlines the pioneering application of a reinforced concrete (RC) composite shear wall system, utilising PPVC technology, in the construction of a 40-storey residential development in Singapore.

INTRODUCTION The Clement Canopy is a high-rise, residential development located at Clementi Avenue 1 in Singapore.

It comprises two tower blocks of 40-storey apartments, with ancillary landscape, swimming pool and communal facilities at ground level. There is a multi-storey carpark with one basement level, linking the two towers. There are a total of 505 residential units in the development.

With support from BCA, TW-Asia Consultants Pte Ltd, the Civil & Structural Consultant, conducted research on RC PPVC technology and pioneered the design of a composite shear wall structural system, using this

To raise productivity, the Singapore construction industry has been encouraged to embrace the Design for Manufacturing and Assembly (DfMA) approach where significant portions of the work are done offsite in a controlled factory-environment. Prefabricated Prefinished Volumetric Construction (PPVC) is one such advanced and highly productive construction technology that speeds up construction significantly.

The Clement Canopy has adopted a RC PPVC system for the two residential tower blocks, in accordance with the requirements in Singapore, outlined in the Building and Construction Authority’s (BCA) Code of Practice on Buildability 2015.

The Temporary Occupation Permit (TOP) for the project was obtained in 1Q 2019. At the time of project completion, The Clement Canopy was the tallest building in the world, among projects that had adopted the RC PPVC system.

NEW RC PPVC TECHNOLOGY The developer of the project is United Venture Development (Clementi) Pte Ltd, a joint-venture between UOL Group Ltd and SingLand Homes Pte Ltd. UOL Group Ltd is one of the leading public-listed property companies in Singapore, with a diversified portfolio of development and investment properties, hotels and serviced suites.

––––––––––––––––––––––––––––––––––––––––––––––– 1TW-Asia Consultants Pte Ltd 2Singapore University of Social Sciences 3Building and Construction Authority 22

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The Clement Canopy. Image: Stanley Cheah.

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Site layout plan

technology. Accordingly, TW-Asia Consultants Pte Ltd obtained a Singapore Patent (No: 10201703972W) for its PPVC system.

It was through research, testing and continual development that this unique composite shear wall structural system was devised as one of the technical solutions for the PPVC methodology.

STRUCTURAL SYSTEM While the PPVC technology is new to the local construction industry, the core engineering design principles for structures and foundations, including compliance with design codes, remain the same as in conventional construction.

The superstructure comprises mainly two 40-floor tower blocks, ground-floor podium, and four levels of carpark (one level at basement and three levels above ground). The foundation system for the two tower blocks comprises bored piles whilst that for the podium and multi-storey carpark comprises jack-in spun piles. The superstructure system for the multistorey carpark adopts the one-way, full precast RC beam & slab system.

The superstructure for the two tower blocks adopts the RC PPVC system for a minimum 65% of floor area, in compliance with BCA’s Code of Practice on Buildability 2015. The balance of the floor area, which is mainly at the corridors, comprises conventional precast RC beams and slabs that link the PPVC modules to the lift & staircase shelter cores. The corridor floor structures provide an effective connecting mechanism to transfer lateral loads from the PPVC modules to the core walls.

DESIGN CODES AND STANDARDS The design of the structures is in complieance with the following design codes and standards: Loading • SS EN 1991-1-1: 2008 - General Actions - Densities, Self-weight, Imposed Load for Buildings • SS EN 1991-1-4: 2008 - General Actions - Wind Actions • NA to SS EN - Singapore National Annex to the relevant Eurocodes Design • SS EN 1990: 2008 - Basis of Structural Design • SS EN 1992-1-1: 2008 - Design of Concrete Structures • NA to SS EN - Singapore National Annex to the relevant Eurocodes THE SINGAPORE ENGINEER November 2020

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PPVC SYSTEM Modularisation For a PPVC project to be successful, early coordination among the Client, Architect, Engineers and Main Contractor (Builder) is essential to firm up the floor layout, in consideration of the Client’s requirements, factors and constraints affecting the PPVC modularisation, and transportation & logistics. Early confirmation of layout is also important to prevent abortive work that is counterproductive to the downstream activities.

Generally, the size and dimensions of modules are controlled by the transportation constraints and hoisting capacity of tower cranes.

In compliance with Singapore Land Transport Authority (LTA)’s regulatory requirements, to avoid police escort, the width of modules is to be contained within the 3.4 m overall transport vehicle width. The height of the modules and that of the trailer bed should also be considered, if the transportation route involves passing below overhead bridges and gantries with a clearance of 4.5 m.

Tower 1 PPVC modularisation

In addition, the roads around the site, site access and holding areas need to be studied properly, in order to facilitate truck deliveries, manoeuvring of vehicles, temporary storage and hoisting of the modules.

For ease of fabrication of the PPVC modules and connecting and installing them on site, such that productivity is improved, the PPVC modularisation considered the following: • The PPVC modules should be rectilinear in shape, as much as possible.

• The PPVC wall thickness should be uniform and standardised, as much as possible.

• The PPVC walls within each module should be aligned, as much as possible.

Tower 2 PPVC modularisation

For The Clement Canopy project, there are in total 1866 PPVC modules, including 862 in Tower 1 and 1004 in Tower 2.

The PPVC module sizes and weights are as follows: • Largest module size: 3.1 m (W) x 8.35 m (L) x 3.15 m (H) • Smallest module size: 3.0 m (W) x 5.75 m (L) x 3.15 m (H) • Maximum width of module: 3.1 m • Height of module: 3.15 m • Weight of module: 14 tons to 29 tons Floor slab The floor structure comprises an RC slab spanning across the module walls. The slab also works as a horizontal diaphragm, transferring lateral loads to core walls at staircase shelters and lift shafts.

Ceiling slab The ceiling structure comprises an RC slab supported on the perimeter walls or beam. Besides helping to brace the walls during transportation and installation, it also supports ceiling finishes and acts as a working platform during the PPVC installation process.

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PPVC concrete carcass components: The typical PPVC concrete carcass comprises a floor slab, two structural side walls, a ceiling slab and nonstructural end wall.

RC walls The wall structure comprises RC walls located on two long sides of the modules, supporting the top ceiling slab and bottom floor slab during lifting and transportation.

These walls are connected with the walls of the adjacent modules via reinforcements in high strength grout within the joints to form a sandwiched composite structural wall. The sandwiched wall system is designed to behave as a single composite entity subjected to compression and bending actions. These walls are load-bearing and participate in the lateral load-resisting mechanism of the building.

CIVIL & STRUCTURAL ENGINEERING

Ceiling height With a 3.15 m floor-to-floor height, the PPVC module system is able to achieve a maximum clear height of 2.790 m.

Horizontal floor diaphragm action The horizontal floor diaphragm action is achieved by connecting the walls and slabs of the adjoining PPVC modules together, using high strength grout and reinforcement, and linking the modules together to the in-situ floor slabs and lift/staircase shelter core walls.

TOWER LATERAL LOAD PERFORMANCE ETABS software was used to model the performance of the tower blocks under lateral loads. The building top displacement and inter-storey drift ratio are controlled to be less than 1/500.

The performance of the towers under lateral loads are as follows: Block 1

Block 2

Total building top displacement ratio, δ/H

1/1235 ≤ 1/500

1/1178 ≤ 1/500

Inter-storey drift ratio, δ/h

1/965 ≤ 1/500

1/909 ≤ 1/500

Lateral displacement under wind actions

Mode

Block 1

Block 2

1

4.74

4.92

2

3.95

4.06

3

3.51

3.05

Mode shape - time period(s)

TOWER ROBUSTNESS The tower blocks have been checked for robustness under notional horizontal load to ensure they are capable of resisting a notional design ultimate horizontal load applied at each floor or roof level, simultaneously equal to 1.5% of the characteristic dead weight of the structure, between mid-height of the storey below and mid-height of the storey above, in accordance with SS EN 1992-1-1:2008 & the Singapore National Annex.

The PPVC modules are linked together and to the in-situ floor slabs and lift/staircase shelter core walls.

Structural ties, such as horizontal floor ties and vertical ties, are provided and checked to comply with the provisions in SS EN 1992-1-1:2008 & the Singapore National Annex.

DURABILITY The structures have been designed to Structural Class S4 (Design working life of 50-years) with Exposure Class XC3 (Corrosion induced by carbonation - moderate humidity) to SS EN 1992-1-1:2008 & the Singapore National Annex.

Overall 3D Model

FIRE RESISTANCE The structures have been designed for a fire resistance of 1.5 hours. Fire compartmentalisation is achieved by the separation of floors by the floor slabs, separation of vertical compartments by RC wall or rated partition. For plumbing risers located within the PPVC units, the horizontal compartmentalisation is maintained with the risers segmented into separate compartments at each floor.

PPVC WALL PROTOTYPE LOAD TESTS Prototype tests were carried out to study the behaviour of the sandwiched composite walls under the actions of compression and bending. The test results show that the sandwiched wall panels are able to work as a single composite entity.

Typical Floor Models created using ETABS

Compression test The test sample was loaded with upto two times the working load and it was able to sustain the load without failure. No delamination was observed at the concrete/ grout interface and hence, the sample was able to behave as a single composite entity under compression.

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Bending test The test sample was loaded until it failed. The sample was observed to have failed because of bending, with flexural crack lines forming on the surface. No delamination was observed at the concrete/grout interface and hence the sample was able to behave as a single composite entity under bending.

PPVC CONCRETE CARCASS FABRICATION The typical PPVC module concrete carcass comprises a floor slab, a ceiling slab, two structural side walls and end non-structural wall/door/window. The concrete carcass, with the embedded pipes for M&E services, were manufactured in Johor, Malaysia. The concrete carcass was built using a 2D fabrication method. The fabrication of the module walls was done first, followed by the fabrication of the slab. A structural ponding test was carried out at the precast factory to check for watertightness of the floor structures and the wall/slab joints.

Compression test set-up

Bending test set-up 26

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Fabrication of module wall

Fabrication of module floor slab

Completed PPVC concrete carcass ready for delivery to fit-out factory

CIVIL & STRUCTURAL ENGINEERING

The following critical activities, including checking, were carried out: • The checking and control of module dimensions, verticality and levels, to ensure that they are within tolerances, to ensure that the impact to the GFA and net usable space, is minimal.

• Ensuring that the precast mould is rigid and stable, with proper mechanisms to adjust dimensions, and checking the dimensions of the modules after mould assembly and after demoulding.

• Ensuring that the M&E services embedded in the concrete carcass are coordinated properly and accurately with the adjacent modules, so that the connection of the modules on site, later on, would be accurate.

TRIAL INSTALLATION The PPVC modules for each residential unit had to be subjected to trial fitting at the fit-out factory, to ensure module levels and dimensions are correct and the adjoining modules match each other, before delivery to site for final installation.

PPVC FIT-OUT WORKS The completed PPVC concrete carcasses were then delivered to the fit-out factory in Singapore for further architectural finishing works (installation of floor and wall finishes; painting work, as well as installation of window frames & glazing, doors, and wardrobe & cabinets) and M&E fit-out works (installation of water & sanitary pipes, electrical conduits & ducting, electrical sockets and light switches), as per the requirement in the COP on Buildability 2015. Waterproofing works were also carried out in the fit-out factory to ensure water-tightness of the wet areas.

Element

Minimum level of completion off-site

Floor finishes

80%

Wall finishes

100%

Painting

100% base coat, only final coat is allowed on-site

Windows frame & Glazing

100%

Doors

100%, only door leaves allowed for on-site installation

Wardrobe and Cabinets

100%, only wardrobe and cabinet doors allowed for on-site installation

M&E including water & sanitary pipes, electrical conduits & ducting

100%, only equipment and fixtures allowed for on-site installation

Electrical sockets and light switches

100%, only light fittings allowed for on-site installation

The minimum level of finishing and installation of fittings to be completed off-site, as per the COP on Buildability 2015.

Architectural finishing and fit-out work in progress

Installation of M&E pipes and fittings in progress THE SINGAPORE ENGINEER November 2020

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The following critical activities, including checking, were carried out: • Markings were made on a flat platform base, similar to a floor layout plan, and alignment guide pins were provided.

• Modules were placed as per the markings on the drawings and the platform.

• Floor levelling and verticality were checked.

• All finishing and fit-out works were completed in place.

• Proper labelling (QR coding) was done for the completed modules that were ready for delivery to site.

INSTALLATION OF PPVC MODULES ON SITE Upon delivery of the PPVC modules to site, heavy duty tower cranes with lifting frames were used to hoist the PPVC modules to their final position in the building.

Among the main challenges during installation was, for example, ensuring that the lifting frame and PPVC module were concentric so that the module does not tilt during hoisting and final positioning. The surface of the concrete that would come into contact with the first layer of modules had to be levelled, the positions of walls had to be surveyed and marked, and alignment guide pins were provided to facilitate positioning of modules.

Suitable locations had to be found for positioning the tower cranes, taking into consideration the reach of the cranes as well as their lifting weight compared to the weight of the modules. The space available for delivery and offloading of the modules and their temporary storage also had to be considered.

PPVC module arrangement at the fit-out yard, similar to the floor layout plan.

Alignment guide pins were provided at the corners of the PPVC modules to adjust the horizontal dimensions and facilitate installation of the modules. Backer rods and grout stoppers were provided to prevent grout loss during in-situ grouting of the joints.

Upon installation of the PPVC modules, the gaps between the adjoining modules were joined together with high-strength grout, resulting in a composite structural wall system. The PPVC modules were also connected to the adjacent floor structures and lift/ staircase shelter walls.

M&E services in the adjoining modules were connected and light fittings, equipment and fixtures were installed.

Final architectural floor finishing, painting work and the installation of door leaves, wardrobe and cabinet doors, were also accomplished during this stage.

Control of water seepage at the joints of the PPVC modules was generally achieved by applying a layer of fibre mesh and cementitious waterproofing membrane.

Floor layout plan

Trial fitting of adjoining PPVC modules for a typical dwelling unit 28

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Installation of modules had to be done in a planned sequential order, both horizontally and vertically.

CIVIL & STRUCTURAL ENGINEERING

For this project, the total time taken to install the PPVC modules was approximately 12 months. The average floor cycle time was six to nine days. As expected, building the first two to three floors required a longer cycle time, on account of the initial learning curve needed to acquire knowledge on module installation.

M&E services within the modules The M&E services in a typical PPVC module generally include the following: • Vertical stacks used for sanitary pipes • Connections for vertical pipes, using hubless C I pipe fittings or uPVC loose socket fittings.

• Water distribution pipes crossing between modules • Electrical cables crossing between modules with the help of junction boxes

BUILDABLE DESIGN AND CONSTRUCTABILITY Based on the guidelines in BCA’s Code of Practice on Buildability 2015, by adopting PPVC technology, this project registered a marked improvement in the Buildable Design Score and Constructability Score. The total Buildable Design Score achieved was 95 which is higher than the minimum required score of 88, while the total Constructability Score for this project was 67 which is higher than minimum required score of 60.

MANPOWER PRODUCTIVITY By adopting PPVC technology, the manpower productivity achieved for this project site was 0.613 m2/manday. Compared with the Singapore Year 2017 Industry Average Project Productivity Data for Residential (non-landed) projects, which shows a manpower productivity figure of 0.357 m2/manday, there is a 72% productivity improvement as a result of using PPVC technology for The Clement Canopy project.

CONCLUSIONS • This project has successfully adopted the PPVC technology for the RC composite shear wall system in the construction of the two 40-storey residential towers in Singapore.

The M&E services within the modules include sanitary pipes, potable water distribution pipes and electrical cabling.

TRANSPORTATION & LOGISTICS To ensure the successful adoption of the PPVC system in the project, the transportation & logistics had to be planned and coordinated properly, thereby establishing a smooth supply chain for the delivery of modules to the different locations for the various stages of work, from production to final site installation. The following processes were involved in the adoption of the PPVC system.

• Fabrication of the concrete carcass for the PPVC modules in the precast factory • Application of architectural finishes / installation of M&E fittings to PPVC modules in the fit-out factory • Installation of PPVC modules on site In this project, the average floor cycle time for module installation on site was about seven days, the fittingout works at the fit-out factory was typically one to two floors ahead, and concrete carcass production at the precast factory was typically two to three floors ahead.

• The adoption of the PPVC system in this project has achieved a marked improvement in the Buildabile Deign Score and the Constructability Score, based on the guidelines in BCA’s Code of Practice on Buildability 2015, with 95 points and 67 points, respectively. The project also achieved a manpower productivity of 0.613 m2/manday, which is more than the manpower productivity figure included in the Singapore Year 2017 Industry Average Project Productivity Data for Residential (non-landed) projects.

• Advantages realised from the adoption of the PPVC system in this project are as follows: - Improved productivity and hence early project completion - Improved site safety as on-site activities are reduced tremendously - Improved quality of end product as most activities are done in a factory-controlled environment - Vast reduction in noise and dust pollution on the job site

ACKNOWLEDGEMENT The authors gratefully acknowledge the involvement and support of all the project team members who have contributed one way or another to the successful completion of the project.

REFERENCES 1. Code of Practice on Buildability 2015 Edition – BCA Publication 2. Design for Manufacturing and Assembly (DfMA) – BCA Publication THE SINGAPORE ENGINEER November 2020

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CIVIL & STRUCTURAL ENGINEERING

Delivery of a PPVC module to site

Installation and stacking of PPVC modules

Hoisting of a PPVC module 3D view of PPVC modules in a typical residential unit

Final positioning of a PPVC module 30

THE SINGAPORE ENGINEER November 2020

Checking of joints between adjoining modules before in-situ grouting

CIVIL & STRUCTURAL ENGINEERING

PROJECT DATA Project The Clement Canopy Location Clementi Avenue 1 Site area 45,633 m2

Installation of PPVC modules commenced in April 2017, for Tower 2, and in May 2017, for Tower 1. Photo taken in May 2017.

GFA (including bonus balcony & PES GFA) 50,196.3 m2 Gross Plot Ratio (including bonus balcony & PES GFA) 3.85 Number of tower blocks 2 Total number of storeys 40 Building height AMSL 140 m Typical storey height 3.15 m

Installation of the PPVC modules in progress. Photo taken in November 2017.

Total number of residential units 505 Number of residential unit types 8 Project contract period 36 months Contract commencement date 1 June 2016 Project TOP 1Q 2019

PROJECT CREDITS Client United Venture Development (Clementi) Pte Ltd Architect ADDP Architects LLP Main Contractor Dragages Singapore Pte Ltd Civil & Structural Consultant TW-Asia Consultants Pte Ltd

The installation was completed in 12 months, that is, in March 2018, for Tower 2, and in April 2018, for Tower 1. Photo taken in April 2018.

M&E Consultant J Roger Preston (S) Pte Ltd

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PROJECT APPLICATION

OFFICE COMPLEX PLANNED ENTIRELY IN 3D The project also uses digital solutions for formwork positioning and concrete monitoring.

When the Citygate office complex in Göteborg, Sweden, was designed, the planners were not just thinking about square metres and building height, they also placed great importance on sustainability.

As well as being a new landmark for the Gårda business district, the building will be a flagship for ecological construction and social responsibility. For example, using special ‘green concrete’ will save 250 t of carbon dioxide.

The façade is being made from recycled aluminium, thus saving natural resources. The plans are intended to secure LEED (Leadership in Energy and Environmental Design) certification for the completed building.

Ecological building construction is not the only important issue for Skanska, the project’s developer and construction contractor. The well-being of the future users has equal priority, and Citygate will receive the WELL Building Standard certification on completion. To meet this standard, the building must meet several requirements, such as good access to daylight and electric lighting with appropriate colour temperatures.

BIM (Building Information Modelling) is also playing a significant role in the construction process. Using BIM, buildings can be planned, built and operated more efficiently and by using fewer resources. Defined procedures and processes were established in the early project stage.

The 3D formwork planning for the building, that the BIM experts drew up, was particularly important for providing crucial input about feasibility and savings potential at an early stage, thus helping the customer to optimise processes.

planning delivered by Doka seamlessly into its own Revit model.

A digital collaboration network of project participants was set up in the construction project management software BIM 360, which provided all participants with a shared 3D model that everyone could access without the need for any other custom software. This meant that clashes could be identified earlier (e.g. between the insert-moulded horizontal and vertical tensioning cables for prestressing) and eliminated before execution.

DokaXact and Concremote save time and ensure accuracy

Before the official start of construction, engineers from Skanska, Doka (who provided the formwork solutions) and Alimak (who provided the construction hoist) were able to move virtually through the 3D building core, inspect the Doka SKE50 automatic climbing formwork in detail, and clarify interaction with the construction hoist to ensure access at every construction stage.

DokaXact has a decisive role in achieving workflow efficiency and ensuring precise construction of Citygate's building core. The system is based on measurement sensors installed at predefined points of the formwork, communicating wirelessly with a central processing unit.

Surveyors and the site construction team use DokaXact to quickly and accurately position the wall formwork on the automatic climbing system.

However, before reaching this phase, Doka's BIM experts created 3D formwork solutions using the DokaCAD for Revit planning software. DokaCAD for Revit is an Autodesk Revit plug-in that allows native, automated formwork planning in BIM software. One of the major advantages in using this system was that the customer was able to integrate the formwork

Using the DokaXact app, which guides the construction site team through the process, step by step, the formwork can be positioned for the next concreting

3D planning and digital project management

32

Citygate, a 144 m office complex in Gårda, Göteborg, Sweden, will be completed in 2021. Image: Skanska.

THE SINGAPORE ENGINEER November 2020

“DokaXact makes life easier for the surveyors, who do not have to be present as often during adjustment of the formwork panels. That saves time”, said Niklas Jarlström, Production Manager, Skanska.

PROJECT APPLICATION

The planning software, DokaCAD for Revit, was used to draw up 3D formwork plans taking into account safety, time and costs.

The building is currently growing skywards with the help of Doka's SKE50 plus automatic climbing formwork.

stage with millimetre accuracy. Data about the current position and progress are transmitted via a cloud and can be viewed and re-used from anywhere.

DokaXact has a decisive role in achieving workflow efficiency and ensuring precise construction of Citygate's building core.

“Our specialist teams and the surveyors save lots of time during the formwork adjustment. The app is very reliable and easy to operate”, said Daniel Dahlgren, Supervisor at Svensk Armering & Betongbyggen AB, the subcontractor.

The entire inner formwork in the building core, 48 m long and with an area of 220 m², is positioned in only 25 to 30 minutes. Getting one side of the formwork positioned accurately is essential for the installation of the reinforcement in accordance with the plans. The ±10 mm construction tolerance for the building core was maintained throughout each storey and was confirmed by measurements of the surveyor.

Concremote is used to improve the planning of the construction project, but that is not all. It gives the client access to real-time data from anywhere, any time. This means that information about the concrete performance can be analysed and appropriate construction measures can be launched at the right time, e.g. formwork striking.

In the Citygate project, the real-time concrete strength data is being used to achieve the planned cycle time of one storey per week.

Concremote is used to achieve the planned cycle time of one storey per week.

SKE50 plus automatic climbing solution Due to the required space inside of the building core, the SKE50 plus automatic climbing formwork with a mast system was used. This allows enough clearance to lift prefabricated wall and ceiling elements into place, while it is still convenient for striking formwork.

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PROJECT APPLICATION

PROJECT DATA Project Citygate Location Göteborg, Sweden Building type Office building

Height 144 m During a virtual tour of the building, the technicians and the customer were able to get a precise idea of the planned formwork solutions before construction began.

Number of storeys 36

Office space 42,000 m² Start of construction Second quarter of 2020 End of onstruction Second quarter of 2021

PROJECT CREDITS Client Skanska A view into the building core, showing the safe access from the construction hoist to the Doka automatic climbing formwork.

“The solution is a well-thought-out system which simplifies the work and can contribute to keeping cycle times short”, said Mr Jarlström.

The Monotec tie-rod system is used at the upper waler level of the Top 100 tec large-area formwork.

The tie-rods can be easily operated from the outer top platform, which speeds up forming works under safe working conditions and avoids the need for ladders and additional scaffolding on the inside. For efficient installation of the prefabricated reinforcement cage, the SKE50 plus automatic climbing formwork with a travelling unit was used for the outer platforms. This features a wall formwork that can be retracted by up to 95 cm.

For safety reasons, specially built stairs and ladders were used as walkways between the different levels.

Safe access from the construction hoist to the Doka automatic climbing system was also ensured throughout construction.

All images by Doka, unless otherwise stated 34

THE SINGAPORE ENGINEER November 2020

Subcontractor Svensk Armering & Betongbyggen Architect Henning Larsen Architects Formwork solutions provider Doka

CONTRIBUTION BY DOKA Products SKE50 plus automatic climbing formwork Framax Xlife framed formwork Top 50 large-area formwork Top 100 tec large-area formwork Monotec tie-rod system DokaXact formwork positioning system Concremote concrete monitoring system Services 3D planning with DokaCAD for Revit and BIM 360 Formwork instructors

PROJECT APPLICATION

COLD MILLING MACHINES

SOLVE BIG CHALLENGE They were used to precisely mill the spillway chute of the Oroville Dam, the highest dam in the US.

Temporary solution makes milling in two passes necessary At an altitude of 235 m, the earthfill embankment dam on Lake Oroville holds back the waters of the Feather River. After several weeks of rainfall, the dam reached its maximum water level of around 4.3 billion mÂł in the winter after only 50 days. As a result, the owner, the California Department of Water Resources, had to initiate flood control measures at an early stage. The water was discharged in a controlled manner over the top of the dam structure at the level of the dam crown and the adjacent spillway.

Due to the large quantities of water and the extremely high water pressure, however, the 55 m wide, main concrete spillway eroded to such an extent that rehabilitation was unavoidable. The damage was initially minimised provisionally by filling the erosion in the surface with rolled concrete, so that the owner could open the overflow system during the winter months, if necessary, explained Chris Anderson, Project Manager at the subcontractor, Anrak, who provided the milling service. This temporary material

had to be removed prior to final concrete paving with Portland cement, however, in order to achieve the desired surface quality. To complete this task, the contractor decided to use two cold milling machines from Wirtgen.

Ensuring reliability and precision Eight days had been scheduled for the removal of the first layer of rolled concrete.

The lower section of the spillway was about 300 m long. The milling depth required was approximately 5 cm. This job was performed by the W 2100 equipped with an ECO Cutter milling drum. This milling drum is fitted with up to 50% fewer picks at larger tool spacings (LA) than a standard milling drum. Fewer picks mean a lower cutting resistance, making it possible to mill hard surfaces such as concrete. This process was followed by the W 210i with a standard LA15 milling drum to give the milled surface the finer texture required to pave the new concrete layer.

During the job, both machines used the Level Pro leveling system developed by Wirtgen.

At an altitude of 235 m, the embankment dam on Lake Oroville holds back the waters of the Feather River. This makes it the highest dam in the United States.

THE SINGAPORE ENGINEER November 2020

35

PROJECT APPLICATION

Anrak’s CEO, Tom Schmidt, had high praise for the Wirtgen milling machine used together with the Level Pro system. He said, “It is both reliable and extremely precise. The evenness of the surface is perfectly uniform and the machine always has excellent traction. The latter is important when milling rolled or Portland cement concrete. And the vibrations that are unavoidable when milling such a hard surface do not affect the Level Pro system”.

Logistical challenges After the flat-bed trucks had transported the cold milling machines to the upper end of the spillway, the machines were lifted onto the structure with the aid of lattice boom cranes and driven onto the area in need of rehabilitation via specially constructed ramps.

Here they faced the next challenge - milling on a 30° gradient. This challenge was solved by attaching steel cables with a total length of more than 450 m to the blades of a large wheel loader and to the rear of the large milling machines, thus securing the machines while work was being carried out.

In the process, the heavy steel cables were attached to several hundred trolleys that are normally used for transporting heavy furniture in order to prevent them from rubbing against the ground.

“We used the trolleys to prevent the texture of the freshly milled concrete surface from being damaged”, explained Tom Chastain, Applications Specialist at Wirtgen America.

onto tracked vehicles with a capacity of 5 m³. These machines are mainly used in open-cast mining, but their manoeuvrability also made them valuable for steep gradient milling at the Oroville Dam. As soon as the tracked vehicles were filled, they unloaded the milled material at the lower end of the spillway so that it could be transported to a nearby concrete plant.

There, the concrete milled material was reprocessed into new concrete for the subsequent construction project.

After the ‘milling the spillway’ sub-project had been reliably completed within the scheduled time-frame, the entire rehabilitation project costing USD 1.1 billion was completed on schedule after around two years.

All images by California DWR

Wirtgen cold milling machines prepared the Oroville Dam’s spillway for the repair project.

Application expertise and safety The machines have a working width of 2.2 m, and it took an average of two hours to remove an entire length.

“In order to achieve the desired surface quality, but also for safety reasons, the cold milling machines were operated at a low advance rate of approximately 3 m/ minute”, said Chastain.

In the end, the W 2100 and the W 210i had each milled 28 full lengths. The cold milling machines loaded the milled material directly 36

THE SINGAPORE ENGINEER November 2020

Before the cold milling machines could begin their work, they were lifted by lattice boom cranes, and placed on the surface to be milled.

PROJECT APPLICATION

Steel cables attached to a wheel loader secured the Wirtgen cold milling machines.

Safety played an important role during the rehabilitation project. In order to protect the workers and their equipment, cargo containers secured the lower end of the spillway.

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PRODUCTS & SOLUTIONS

MANITOU ASIA INTRODUCES THE 220 TJ-X AND 220 TJ+-X AERIAL WORK PLATFORMS Manitou Asia has introduced two high-capacity compact aerial work platform (AWP) models - the 220 TJ-X and 220 TJ+-X. Manitou Asia is part of the Manitou Group, a world leader in equipment for operation on rough terrain, material handling, access and earthmoving.

Capable of reaching a height of 22 m, the 220 TJ-X is light and compact, and has a basket with a capacity of of 230 kg, while the 220 TJ+-X has a basket which can take up to 350 kg of load. This capacity remains, regardless of the articulated arm’s position or the telescopic extension.

The machine’s compact dimensions give operators the desired manoeuvrability, especially on construction sites with a heavy load of machines. With an overall fold-up size of only 8.04 m, the 220 TJ-X is built to facilitate transportation and meet the expectations of rental companies.

Powered by a 4-cylinder, 26 kW diesel engine with a variable speed pump, the telescopic booms of the 220 TJ-X and 220 TJ+-X ensure ease and precision when in use. A built-in system also automatically adjusts the engine’s power accordingly, to reduce fuel consumption and total cost of ownership.

The machines are also installed with a hydraulic block to provide smooth and rapid movements with complete safety. The jacks taper off before stopping, giving added comfort and eliminating risks arising from jerky movement. A system patented by Manitou automatically adapts the speed according to the degree of extension of the boom, to maintain constant speed regardless of the basket’s position.

Designed for use in tough conditions, the machines are ideally suited to handle uneven ground and environments with high salt content and high temperatures.

For example, in the San Juan viaduct bridge building project in the Philippines, with a tight working environment and multiple crossings, the default 4-wheel steer of the 220 TJ+-X enabled the operators to manoeuvre it around with ease. Its rough terrain capability also tackled all kinds of crossings on site while its versatility made it possible for the machine to be used on a floating platform during construction as the viaduct was built on a canal.

Apart from being highly durable and able to boost productivity, these AWP machines are equipped with IIIA engines to reduce noise during use, to as low as 106 decibels.

Like all new Manitou machines, the 220 TJ-X & 220 TJ+-X are connected machines to enable users to optimise usage and maintenance of their machines. This allows Manitou to accurately analyse data to reduce the total cost of ownership for operators.

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THE SINGAPORE ENGINEER November 2020

The new aerial work platform models can help to boost productivity.

Image: Manitou Group.

AWP model

220 TJ-X

220 TJ +-X

Type of wheel drive (WD) / wheel steer (WS)

4WD / 2WS

4WD / 4WS

Capabilities

Oscillating axle + differential locking 360° continuous rotation

Basket capacity

230 kg per 2 persons

350 kg without restriction per 3 persons

Basket dimensions

2,100 x 800 mm

2,300 x 900 mm

Working outreach

17.6 m

17.8 m

Machine dimensions

9.8 x 2.49 x 2.47 m

10 x 2.49 x 2.52 m

Weight

11,850 kg

13,800 kg

Technical specifications of the 220 TJ-X and 220 TJ+-X

PRODUCTS & SOLUTIONS

NEW AERIAL WORK PLATFORM

INCREASES OPERATIONAL EFFICIENCY

The 260 TJ-X aerial work platform is designed to increase the operational efficiency of worksites. Images: Manitou Group.

The 260 TJ-X aerial work platform (AWP), from Manitou Asia, is equipped with a supersized basket that can lift three operators or 400 kg in load up to a height of 25.9 m. The machine is designed to increase the operational efficiency of any worksite.

The 260 TJ-X’s overall unfolded length of 7.88 m makes transporting it a breeze. Optional features of the machine include the Easy MANAGER and the SMS (Safe Man System), an operator protection system that is fully compliant with industry safety standards.

Targeted at operators requiring a large working area and flexibility of use, the 260 TJ-X is built with an offset of 19.7 m, pendulum travel of +/-70° and capacity for continuous 360° rotation of the turret. Its off-road and four-wheel drive abilities also assure a high-crossing capacity across difficult terrains.

The machine’s performance has already benefitted Kwan Yong Construction for its school building project in Singapore. Limitations in the previous machine used had undesirably increased the frequency of transferring raw materials to the specified height, causing delays in the project timeline. After switching to the 260 TJ-X, Kwan Yong was able to lift significantly more raw materials with one transfer, along with tools and other heavy equipment, owing to the 400 kg capacity basket. The time-saving proved crucial in enabling the contractor to complete the project on schedule.

Size is not the only advantage of the 260 TJ-X. Its high-precision hydraulic movements ensure maximum operator comfort and its system to reduce noise to 106 decibels effectively moderates noise pollution.

In addition, the AWP’s remote control feature gives users a clear view of the entire AWP and the ability to steer the basket to the optimal position.

The machine also reduces the Total Cost of Operation (TCO) and is equipped with a diagnostic aid for faster maintenance operations and minimal machine downtime.

Height

Basket capacity

Machine dimensions

Weight

26 m

400 kg

2.48 m x 7.88 m

16,380 kg

Technical specifications of the 260 TJ-X THE SINGAPORE ENGINEER November 2020

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PRODUCTS & SOLUTIONS

NEW CATERPILLAR DOZER LOWERS OWNING AND OPERATING COSTS The new Cat D9 dozer, from Caterpillar, replaces the D9T model and offers customisable configurations to meet application needs around the world. Built on a legacy of longevity and proven reliability in the field, the new Cat D9 lowers overall costs per unit of material moved by up to 3%. Efficiencies gained through a new torque converter with stator clutch reduce fuel consumption by as much as 5%, and the new dozer reduces maintenance and repair costs by as much as 4%.

The new dozer features the proven Cat C18 engine which has a range of exhaust after-treatment solutions available.

The D9 also features differential steering for a tight turning radius and the ability to maintain ground speed while turning, to keep productivity high. The suspended undercarriage delivers more track contact with the ground for less slippage and greater productivity.

The versatile D9 can be equipped with blades and attachments from a wide range available, enabling it to work efficiently in a variety of applications, including production dozing, site maintenance, fleet support and ripping. For companies engaged in heavy construction, quarry and aggregates, landfill, bulk materials handling and forestry applications, the D9 Dozer is expected to deliver low owning and operating costs while maintaining high productivity.

standard rear-view mirrors, the new D9 affords the operator clear lines of sight to front and rear working areas. The optional four-camera system offers a 360° view around the machine and ripper to further enhance operating safety. Adding bottom guard retention pins and eliminating lift cylinder grease points also bolster safety.

A new design with advanced ergonomics, the cab features intuitive controls that are easy to access and operate. Its cloth air-suspension seat provides operator comfort throughout the entire shift. The suspended undercarriage reduces shock load transfer to the undercarriage by as much as 50%, resulting in a smoother and more comfortable ride. The new operator station comes fully equipped with large, highdefinition touchscreen displays and new electronic architecture that is scalable to meet the customer’s technology needs.

Integrated technology Sensors integrated into the new Cat D9 provide access to advanced operating technology. Machine management tools provide customers with dozer information. Other features include the Available Automated Blade Assist, the Cat AutoCarry option and the Automatic Ripper Control option.

Reduced maintenance and enhanced safety Featuring a frame that absorbs and withstands highimpact shock loads encountered in severe applications, the new D9 offers design improvements that reduce maintenance and repair costs. The newly integrated AutoLube system results in fewer grease points to limit daily maintenance procedures. Extended filter change intervals, simple component removal and continuous fluid level monitoring also aid in further lowering operating costs.

A new ground-level service centre provides convenient access to the engine shutdown switch, access/egress lighting and optional powered ladder operation. With

The new Cat D9 dozer.

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