Building Technology I - Precast Construction

BUILDING TECHNOLOGY I INDUSTRIALIZED BUILDING SYSTEM PROJECT 1 2018

Angela Wee Kah Man 0322970 Cha Yun Xian 0322048 Chin Shee Wei 0322499 Danica Gan Jia-En 0323708 Shum Li Sze 0322822

C O N T E N T 01 / Introduction of IBS 02 / IBS Design Concept and Framework 03 / Precedent Studies 04 / Technical Drawings 05 / Construction Sequence and Fabrication Process 06 / Construction Details 07 / Schedule of IBS System and Modular Components 08 / IBS Score 09 / References

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I N T R O D U C T I O N

What is IBS? History of IBS Type of IBS

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WHAT IS IBS ?

Industrial building design system (IBS) is also known as Prefabricated Construction and off-site Construction. It is a method of construction where the structural components of a building are fabricated under a controlled environment. They are produced off-site then later transport and assembled at the construction site.

It is divided into two systems which are : 1.Open System Open system refers to the IBS components are fabricated by different manufacturers.

2.Closed System Closed System is the IBS components are fabricated by a single manufacturer.

The content of IBS (IBS Score) is determined based on the Construction Industry Standard 18 (CIS 18: 2010); either manually, web application or fully automated CAD-based IBS score calculator.

HISTORY OF IBS

Crystal Palace 1850

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Eiffel Tower 1887

The concept of IBS can be traced back to 1624 in England which is a panelised timber house. During the Industrial Revolution of the 1700s, the first IBS building was a cast iron bridge in Shropshire, England. IBS then became more well known in the industrial field. For example, the Eiffel Tower in Paris, France was built using the IBS system.

IBS IN MALAYSIA

Tunku Abdul Rahman Flats

Rifle Range Road Flats

The implementation of IBS concept by using precast concrete building were introduced in Malaysia in 1966 when the government launched two pilot projects for precast housing which consist of the construction at Jalan Pekeliling Low Cost Flat in Kuala Lumpur (Tunku Abdul Rahman Flat) and the Rifle Range Road Flats in Penang. The aim of these projects is to actually speed up the delivery time and build affordable quality houses.

Kuala Lumpur Convention Center

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Bukit Jalil Sport Complex

Since 1980’s, there were intensive marketing strategies launched by the Malaysian Government to introduce modular coordination, its acceptance has received poor responses by the building industry. As a result even partial introduction of IBS such as lintels and staircase has not been possible.

In the 90s, demand for the new township has seen to increase in the use of precast concrete system in high rise residential buildings. In the booming period of Malaysian construction 1994 to 1997, hybrid IBS application are used in many national iconic landmarks such as Kuala Lumpur Convention Center and Bukit Jalil Sport Complex which were constructed using steel beam and roof trusses and precast concrete. Other than that, Lightweight Railway Train (LRT) and KL Sentral were constructed by using steel roof structure and precast hollow core.

TYPES OF IBS SYSTEMS Since the introduction of Industrial Building System (IBS) in Malaysia, the construction industry underwent a transitional change to become one which is more systematic and mechanised. Based on Construction Industry Development Berhad (CIDB), IBS is structurally classified into six main groups which are :

A. Precast System Precast System is the most used IBS construction method in Malaysia. It is produced by casting concrete in a reusable mold or “form’’ which is then cured in a controlled environment, transported to the construction site and installed. Example of such precast concrete are precast columns, beams, slabs, walls and 3D components such as balconies, staircase, toilets and etc. which are used mainly in schools, apartment, infrastructure projects and etc.

B. Steel Framing System Steel framing system is commonly used with precast concrete slabs, steel columns and beams.

It is used extensively in fast-track construction of skyscrapers, large factories, exhibition halls and spaces that require larger and wider areas. Besides, it is well known for its extensive used for light steel trusses consisting of cost-effective profiled cold-formed channels and steel portal frame system as alternatives to the heavier traditional hot rolled sections.

C. Formwork System Considered as one of the low-level or the least prefabricated IBS. Formwork system generally involves site casting and is subject to structural quality control, the products offer high-quality finishes, and fast construction with less site labour and material requirement.

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D. Block Work System This system includes the interlocking concrete masonry units (CMU) and lightweight concrete blocks. It is usually used for non-structural wall that acts as an alternative to conventional bricks and plaster. They may include a hollow core which make them lighter and improve insulation properties. It has the lowest IBS score in the IBS scoring system.

E.

Prefabricated Timber System

Prefabricated Timber System consists of timber building frames and timber roof trusses. It offers an interesting designs from simple dwelling units to buildings requiring high aesthetical values such as chalets for resorts.

F.

Innovative System

Latest IBS incorporates ‘‘green’’ elements hence considered the innovative system in the industry.

Mixture of two elements such as polystyrene and concrete, to produce IBS components for use in the construction of a wall which has better insulation properties is one of the example of innovative system. Nowadays, with the advancement in technology and innovation, lots of new materials are being introduced in IBS.

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C O N C E P T &F R A M E W O R K

Advantages of IBS Disadvantages of IBS Structural Construction Process

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IBS DESIGN CONCEPT AND FRAMEWORK Advantages: ● ● ● ● ● ● ● ● ● ● ● ● ●

Disadvantages:

Reduction of unskilled workers Elimination of conventional timber props and decrease of timber supports Less wastage Less volume of building materials Increased environmental & construction site cleanliness Better quality control Safer and more organized construction site Reduced construction time Systematic Smooth finish Construction operation is not affected by adverse weather conditions Considerable cost savings due to reduction of workers on site Considerable cost saving due to faster project completion

● ● ● ● ● ● ● ● ● ● ●

Lack of aesthetic value High initial cost Require highly skilled workers Prefabricated elements are inflexible Transportation inflexible Limited supply Less job opportunity Water leakage due to poor connection Cracking Poor humidity control Environmental pollution

Prefabrication Process Of IBS Components

1.Design

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2.Production Line

3.Transportation to Site

4. Assemble & Erection On Site

5.Completion of Final Unit

Structural Construction Process Before construction, to ensure high efficiency and quality of installation, things like method and sequence of assembly, handling method of rigging system, temporary support, joint detail method and etc should be taken into consideration to avoid mistakes in installation of components which will cause structural failure.

1.

2.

3.

4.

Check for site accessibility for the delivery of precast elements Check delivery checklist for correct type, quantity and panel specification Conduct sample measurement to confirm on the accuracy of the dimension of components Check the locations and conditions of lifting

Next phase will be the installation of vertical precast components. First, 1.

2.

3.

4.

Check the positions and alignment of starter bars before installation During installation, check the stability of the erected props before releasing hoisting cable When carrying out grouting work, make sure the joint width between panels are within allowances designed The joint gaps should be consistent to allow for proper installation of sealant or grout to achieve high level of water tightness which can prevent water leakage.

The last phase is the installation of horizontal precast components.Checklist that need to be done are : 1.

2.

3.

4.

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Lifting of beam should be supported minimum at two ends Secure the formwork during casting Check the levelness between each component before sealing them Other will be mostly the same as vertical components casting

P R E C E D E N T S T U D I E S

Seri Jati Shah Alam Seri Baiduri Shah Alam

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SERI JATI APARTMENT @ SHAH ALAM Seri Jati is a low cost apartment located in the vicinity of Shah Alam, Selangor. This residence was developed for the lower and medium income citizens by the renowned SP Setia. Launched in the year 2012, this high density residence was completed in 2014.

The apartment have 6 blocks in total, whereby 3 blocks are 10 storeys high and the other 3 blocks are 11 storeys high, it has total 948 units.

Full IBS Factor: A. Precast 1. Load bearing and non bearing walls 2. Staircase 3. Column, beam, slabs B. Steel Framing System: 1. Prefabricated steel roof trusses

Partially IBS System: Precast system: Walls for roof Form work system: In-situ concrete structure Conventional Construction 1. Foundation 2. Ground floor 3. Transfer beam 4. Reinforced Concrete Slab

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system:

SERI BAIDURI APARTMENT @ SHAH ALAM Seri Baiduri is a freehold apartment located in Shah Alam, Selangor.

The apartment has 4 blocks with 10 storeys each. It has total of 640 units, 16 units per floor. Each block comes with two lifts. This residence was launched in the year 2012 and completed in 2014.

Full IBS Factor: A. Precast system: 1. Column 2. Beam 3. Slab 4. Staircase B. Steel Framing System 1. Steel Roof Trusses C. Precast components: 1. Precast wall, column, beam 2. Precast hollow core slab 3. Precast toilet pod 4. Precast staircase & landing 5. Precast load bearing walls

Partial IBS Factor: 1. Reusable system formwork for in-situ concrete structures 2. Custom window and door sets

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Conventional Construction: 1. Foundation 2. Ground floor 3. Transfer beam 4. Reinforced Concrete Slab

T E C H N I C A L D R A W I N G S

Floor Plans Structural Floor Plans 4 Elevations 2 Sections Exploded Axonometric

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EXPLODED AXONOMETRIC Prefabricated Timber Roof Truss

Doors

Precast Windows

Precast Staircase Hollow Core Slab Cast In-situ Lift Core Precast Planter Box Precast Bathroom Pod Precast Concrete Beam

Precast Concrete Wall

Precast Concrete Column Cast In-situ Stump

Cast In-situ Footing

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S E Q U E N C E &

P R O C E S S

Construction Sequence Fabrication Process

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Footing to Stump

Stump to Ground Beam

1.

1.

2.

3.

2.

3.

4.

5.

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The site is cleared and pegged with the correct position of foundation.

The formwork is built to the side of the pad footing and supported by other wood to prevent the formwork from collapsing when the concrete is being pour into it.

Rebars are bent and tied together before the being lowered and placed inside the formwork.

Stump reinforcements are then erected. The length of rebars are extended beyond the stump level and act as starter bars for column above.

Concrete will set and curing shall be performed to avoid excessive lost of water during hardening.

The formwork is built beside the stump.

Rebars are bent and tied together and placed in the formwork.

Concrete is poured into the formwork and curing shall be performed to avoid excessive lost of water during hardening.

Cast-In-Situ Slab

Pad Footing to Precast Concrete Column

1.

1.

2.

3.

4.

5.

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Erect the slab formwork using conventional scaffold framing and timber combination or using system formwork.

Apply releasing agent using rollers for ease of striking.

Main reinforcement bars laid at bottom layer of the slab spaces evenly according to design or drawings.Tie the reinforcement bars at both ends to maintain the spacing and tie the distribution bars to the main reinforcement bars.

After completing the slab top reinforcement, clean and blow away the dust by using compressed air.Check all the formwork gaps and ensure that they are plugged before concrete placement.

Check the concrete slab surface and ensure it is sufficiently dry after 12 hours.Spray water and flood the concrete to cure and repeat when it’s needed.

2.

Precast columns are installed on top of the stump and secured by a steel base plate joint.

A layer of concrete is cast to secure and protect the joint.

Precast Concrete Column to Precast Concrete Beam

Cast In-situ Lift Core

1.

1.

2.

3.

The lift core is casted on site using the jump form system as it is suitable for construction of multi-floor vertical concrete elements.

Precast Concrete Wall to Skeletal Structure

Precast Bathroom Pod

1.

1.

2.

3.

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Beams are casted in plants away from the structure in a very controlled environment and then sent to site.

Beams are rested on the column’s corbels.

Steel angles are welded to plates anchored in the wall and slab to secure the beams.

With the Skeletal structure intact, precast concrete walls are slotted into place.

The edges of the walls are grouted with cement to seal the gaps.

Metal plates are embedded between wall panels to further secure the walls.

2.

Precast bathroom pods are placed before the covering of the slab.

It is slotted 50 mm below the floor finishes to prevent water spillover.

Hollow Core Slab to Beam Connection

Precast Concrete Staircase

1.

2.

1.

3.

4.

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Hollow core slab are set on bearing pods on concrete beams Steel reinforcing bars are inserted into the slab keyways to span the joint The joint is grouted solid The slab may remain untapped as shown, or tapped with several inches of cast in place concrete

2.

Landing with beam is rested on column on four sides braced with steel plate.

Staircase with anchor plates are then slotted onto the landing, the gaps are grouted with cement.

Superstructure to Timber Roof Truss 1.

2.

3.

4.

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After the completion of the superstructure, prefabricated timber roof truss are secured to the roof beams using angle metal plates and steel dowel.

The roof trusses are arranged at a span of 1000mm.

A ridge beam is used to hold the truss in place.

Purlins are bolted to the rafter to secure the roofing material.

Roof Truss to Roofing Material 1. Roof shingles are then attached to the purlins of the roof.

C O N S T R U C T I D O E NT A I L S

Construction Connection and Details Substructure Connections Column to Beam Connections Slabs Connections Walls Connections Staircase Connections Roof Connections

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CONSTRUCTION CONNECTIONS AND DETAILS

Prefabricated roof truss

Superstructure

Substructure

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Precast system

Cast-in situ

SUBSTRUCTURE CONNECTIONS

Reinforced bars

300 x 300mm stump 900 x 900mm footing

Wire mesh

Reinforced ties

Metal plate with embedded anchor bolts 300 x 300mm Ground floor beam

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150mm cast in-situ slab

COLUMN TO BEAM CONNECTIONS Intermediate beam connection

Edge beam connection

Steel angle welded to plates anchored in wall and slab unit Reinforcement ties Corbel contributes to required bearing Bearing pad

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SLABS CONNECTIONS Slabs to Beam Connection

Slab to Slab Connection

Concrete topping reinforced with steel mesh

Grout fills in the gap between both hollow core slab to them.

Tongue

High-density plastic bearing strips

Concrete topping reinforced with steel mesh

Balcony U-plate

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Grout

Groove

Grout to lock adjacent hollow core concrete slab.

WALLS CONNECTION Slab to Wall Connection

Wall to Wall Connection Adjacent wall

Corner wall Grout

Embedded metal plate Grout to cover the grooves

The void of hollow core slab is grouted at ends to bind into the precast wall

50mm bearing length with high density plastic bearing strips

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Steel dowel extends into the wall panel for structural continuity

STAIRCASE CONNECTIONS

Staircase connection

Landing to brick wall connection Staircase to floor slab connection

Blockwork

100mm bearing

Bearing with metal plate

30mm dowel hole 25mm packing Screed finish

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ROOF CONNECTIONS

Column to roof beam connection Roof beam to roof truss connection

Purlin Wall plate Steel dowels to connect Precast beam to prefabricated roof truss.

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Angle metal plates

S C H E D U L E

Column Schedule Beam Schedule Slab Schedule External Walls Schedule Internal Wall Schedule Foundation Schedule Planter box schedule Door Schedule Windows Schedule Staircase Schedule Toilet Pod Schedule Roof Truss Schedule

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COLUMNS SCHEDULE

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BEAMS SCHEDULE

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BEAMS SCHEDULE

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SLABS SCHEDULE

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EXTERNAL WALLS SCHEDULE

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INTERNAL WALLS SCHEDULE

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FOUNDATION SCHEDULE PRECAST PLANTER BOX SCHEDULE

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DOORS SCHEDULE WINDOWS SCHEDULE

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TOILET PODS SCHEDULE STAIRCASE SCHEDULE

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ROOF TRUSS SCHEDULE

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I B S S C O R E IBS Score Calculations

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IBS SCORE CALCULATION A. Construction Area i) Construction Area Ground Floor = 250.0 m² ii) Construction Area 1st Floor = 250.0 m² iii) Construction Area 2nd Floor = 250.0 m² IV) Construction Roof Area = 250.0 m² Total Construction Area = 1000.0 m²

B. Structural System i) Beams: Precast Concrete Beams ii) Columns : Precast Concrete Columns iii) Floor Slab : Precast Hollow Core Slabs iv) Roof Truss : Prefabricated Timber Roof Truss

C. Wall System i) Internal Wall : Precast Concrete Panel and Cast In-Situ ii) External Wall : Precast Blockworks and Precast Concrete Panel

D. Other Simplified Construction Solutions i) ii)

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Column 300 x 300 mm

Beam 300 x 300 mm Beam 300 x 450 mm iii) Wall 150 x 2400 mm Wall 150 x 3000 mm Wall 150 x 3600 mm Wall 150 x 4200 mm iv) Slab 150 x 200 mm Slab 150 x 750 mm Slab 150 x 1050 mm Slab 150 x 1200 mm

v) vi)

Window 600 x 600 mm Window 1200 x 1800 mm Door 900 x 2100 mm Door 1350 x 2000 mm

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R E F E R E N C E S

BOOKS Ching, Francis D. K. (2011). Building Construction Illustrated. Hoboken, NJ: Wiley.

WEBSITE https://prezi.com/rc7gpflwwpcy/industrialized-buildingsystem/ https://mummyku.weebly.com/uploads/5/2/5/4/52547 687/topic_4_buildability_of_design.pdf http://www.midf.com.my/images/Downloads/Research /EqStrategy/SpecialReports/Construction-IBS_MIDF_140 214.pdf http://cidb.gov.my http://www.ibscentre.com.my/

OTHERS Malaysian Standard 1064 : Part 4 : 2009 Malaysian Standard 1064 : Part 5 : 2009 Malaysian Standard 1064 : Part 10 : 2009 Construction Industry Standard 18 (CIS 18: 2010)

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