Redefining sustainable construction
HIPER PILE ®
The HIPER® Pile redefines deep foundations as low carbon, sustainable and reusable assets.
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Keltbray | HIPER® Pile Overview
Contents INTRODUCTION 04 UK COMMITMENTS & TCC
06
INTRODUCING THE HIPER® PILE
08
HOLLOW PILE
10
IMPRESSION PILE
12
PRECAST PILE
14
ENERGY PILE
16
REUSE 18 USES BEYOND PILING APPLICATION
20
CASE STUDIES
22
HIPER® PILE BENEFITS
26
CONCLUSION 27 ACKNOWLEDGEMENTS 28 REFERENCES 29 CONTACT 31
The HIPER® Pile has the ability to extend and reuse deep foundations, provide added value and reduce whole life emitted carbon.
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Introduction GLOBAL COMMITMENT TO CLIMATE CHANGE
Climate change presents a major threat to the world’s people, environment, economies and health. ICE, 20201
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Keltbray | HIPER® Pile Overview
The UN Intergovernmental Panel for Climate Change (IPCC, 2018) stated that human activities have already caused 1.0°C of global warming above pre-industrial levels. Given the high, and increasing, levels of CO2 in the atmosphere humanity’s immediate challenge is to limit the global temperature rise to between 1.5°C and 2.0°C by 2050.2 Impacts of 1.0°C rise are already being felt globally and many land and ocean ecosystems have been negatively affected. Construction has a vital role to play limiting global warming to 1.5°C. The building and construction sectors are responsible for 39% of all global carbon emissions, with 28% accounting for operational heating and cooling related emissions. Drastic changes are urgently required to manage both embodied and operational carbon.
Future climate-related risks depend on the rate, peak and duration of warming. IPCC, 2018 2
INTRODUCING THE HIPER® PILE
The whole is greater than the sum of its parts. The HIPER® Pile specifically addresses the challenges laid out in the Paris Climate agreement and a number of UN sustainability development goals (UN, 2015) by providing the tools to reduce embodied carbon within the deep foundations industry as well enhancing operational thermal energy efficiencies.3
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UK commitments and the Transforming Construction Challenge (TCC)
THE TIME FOR CHANGE IS NOW The HIPER® Pile development has been funded by UK Research and Innovation (UKRI) as part of the wider Construction 2025 (BEIS, 2013)4 drivers to achieve the following:
33%
reduction in initial construction costs and whole life costs
50%
lower greenhouse gas emissions in the built environment
50%
faster delivery from inception to completion for new builds and refurbishments
50%
reduction in trade gap for construction products and materials
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Keltbray | HIPER® Pile Overview
We are the world’s inventors, innovators and practical problem solvers. With every passing day the challenges posed by climate change grow greater. It is on us to step up and figure out what we can do to help address the problem. Skinner, 2021 4
We are honoured to launch the HIPER® pile at the Institution of Civil Engineers, this product can actively contribute to decarbonising the UK construction market and tackle climate change head on. Now is the time for radical change and the UK is leading the way to meet net-zero carbon targets by setting the world’s most ambitious legislative targets to cut emissions by 78% by 2035, compared to 1990 levels (BEIS, 2021). 5
The HIPER® Pile is a tangible and readily available solution to cut construction related carbon within the foundations needed to support UK infrastructure. It also presents an opportunity to stimulate the renewable thermal energy sector; a vital component to help the decarbonisation of UK power generation.
70%
Approximately 70% of global emissions are a result of infrastructure; from construction to energy consumption through occupancy.6 The HIPER® Pile is an innovative solution to address this statistic.
We want to continue to raise the bar on tackling climate change, and that’s why we’re setting the most ambitious target to cut emissions in the world. The UK will be home to pioneering businesses, new technologies and green innovation as we make progress to net zero emissions, laying the foundations for decades of economic growth in a way that creates thousands of jobs. Prime Minister Boris Johnson, 2021 5 Keltbray | HIPER® Pile Overview
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Introducing the HIPER® Pile It is time to view foundations as intelligent and reusable assets; they are no longer one-dimensional structural elements. The HIPER® Pile is an acronym for the Hollow, Impression, Precast, Energy generating, and Reusable pile. Individual HIPER® benefits can be utilised to meet specific project requirements. Whilst some benefits are interdependent; for example the precast element may only be constructed as a hollow pile, other elements such as impression piles may be incorporated on traditional solid bored piles.
The HIPER® Pile system combines its innovative functions in a novel ‘plug and play.’
HOLLOW Up to 70% material volume reduction
IMPRESSION Improving shaft friction capacity by up to 40%
PRECAST Embracing off site manufacture, improving quality and productivity
ENERGY 60% increase in thermal conductivity and derisks delivery over traditional thermal piles
REUSABLE The solution to enable a fully circular economy within deep foundations
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Keltbray | HIPER® Pile Overview
Arguably there has been no significant innovation within the piling and foundations industry since the development of the CFA pile in the 1960’s. ___ Significant programme and embodied carbon savings can be realised by combining individual elements of the HIPER® Pile; this is further enhanced when integrated with low carbon concrete technologies. The Hollow pile void is well-suited for thermal energy storage and generation to address operational carbon emissions. Use of the void eliminates the construction risks commonly associated with solid energy piles and increases the efficiency of the pile as a heat exchanger. The HIPER® Pile can be considered to be a long term asset for the structure continuing to actively contribute to sustainable whole life cycle models throughout occupation, decommissioning and redevelopment. This is achieved specifically through our ability to warrant its reuse and optional future enhancement in load bearing capacity.
Up to 90% whole life cycle carbon savings are achievable with the full HIPER® suite compared with traditional bored pile foundations.
Keltbray | HIPER® Pile Overview
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HOLLOW PILE Eliminating material, reducing embodied carbon OPTIMISATION BY DESIGN
160
1
140
Concrete volume (m3)
120 Solid pile
100 80
HIPER Pile
60 Material Savings
40 20 0 750
1300
1850
2400
Pile diameter (mm)
50000
2
Capacity (kN)
40000
Solid pile - structural capacity (C32/40)
30000
Solid pile - geotechnical capacity
20000
Hollow pile - structural capacity (C40/50)
10000
Hollow pile - geotechanical capacity
0 750
1300
1850
2400
Pile diameter (mm)
Carbon emissions (tCO2e)
30
3
25 Solid pile carbon
20 15
HIPER Pile carbon
10
Pile reuse carbon offset
5 0 750
1300
1850
Bored pile diameter (m) 1. Concrete volume savings for varying pile diameters 2. Compressive load capacity chart 3. Embodied Carbon chart for varying diameters
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Keltbray | HIPER® Pile Overview
2400
High factors of safety are adopted in the structural design of piles. Structural loads and geotechnical resistance are often imbalanced. At the head of the pile, the necessary structural capacity is at its greatest, and the geotechnical resistance is nominal. Conversely, at the base of a friction pile, the structural load has fully dissipated in the ground, however, the structural capacity remains equal to the capacity at the head of the pile. With a 200mm thick concrete annulus constructed for all pile diameters, the Hollow pile optimises the permissible stress on the concrete section and enables a reduction in concrete volume of between 30% for small diameter piles and up to 70% for larger diameter piles. The reduced structural stiffness of the Hollow pile also encourages incremental strain to develop as load is applied, thereby allowing the pile to mobilise greater resistance in the soil and provide enhanced load bearing performance.
Integrating Hollow piles with low carbon concretes can reduce embodied carbon by up to 80% compared with traditional large diameter solid piles. The Hollow pile optimises the load against concrete consumption; the larger the pile diameter, the greater the savings as a result of a disproportional increase in void diameter. Hollow piles may be cast in-situ or manufactured off-site using precast modular components to further increase efficiency and productivity on site. The Hollow pile is patented by City, University of London and exclusively licensed to Keltbray.
1. Void forming liner installed within pile void 2. Fresh concrete placed to pile base and annulus
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IMPRESSION PILE
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Enhancing shaft friction, reducing material volume and waste DRIVING PRODUCTIVITY IMPROVEMENT
In-situ construction sector programmes are governed by the supply of just-in-time materials. This is particularly true of fresh concrete with the foundations industry consuming approximately half the volume produced in the UK. Productivity in piling is heavily influenced by the availability of concrete, site operating hour restrictions, LDSA guidance (LDSA, 2017) and further complications arise when the piles are constructed with fluid support. Pile bores are generally not permitted to be left open over 12 hours, so drilling commences in the early hours and concrete demand often coincides with other trades later in the day. Production rates are often inefficient to ensure that piles can safely be completed within the shift. 7 The Impression pile was created to maximise productivity by reducing construction risk and optimising pile design techniques. It is a novel technique with inherent flexibility. A bespoke
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2
hydraulically operated tool forms impressions along the exposed pile shaft. Enhancing the shaft profile shifts the mobilisation mechanism away from a traditional concrete : soil interface and towards a more efficient soil : soil interface, meaning a 750mm diameter Impression pile behaves as if it were constructed with a 930mm straight shafted pile. Extensive small scale centrifuge tests and field trials have been conducted on the Impression pile, demonstrating up to a 40% increase in shaft capacity. Increasing shaft capacity allows piles to be shortened, which can avoid the need for deep piles founded in water bearing strata. Eliminating the need for fluid-support piles improves quality control, avoids the need for base grouting, accelerates programmes and mitigates the challenges of storing large volumes of support fluid on congested sites. The Impression pile is subject to 2 patents pending.
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1. Drill pile using conventional rotary bored techniques 2. Impress pile from base upwards 3. Place concrete without pile bore
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1. The impression tool 2. An extensive range of detailed centrifuge model tests carried out at City, University of London 3. Pile behaviour mechanism 4. Small scale Impression piles investigating nodule spacing 5. On board cameras are used to monitor the in-situ bore profile to maintain high quality records during Impression pile construction
3
4
Impression piles are ideally suited to normally consolidated and overconsolidated clays such as those found within the geology of the London basin and elsewhere throughout the UK.
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TECHNOLOGICAL BENEFITS INCLUDE: Up to 40% increase in shaft friction Leaner, more efficient pile designs Pile length or diameter reductions minimising material usage and waste Practical solution to eliminate the need for fluid support piles
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Utilising off-site manufacture within large diameter pile construction FROM CONSTRUCTION TO PRODUCTION
Eliminating the volume of concrete within Hollow piles reduces the weight per linear metre, which therefore offers the unique potential for off-site manufacturing processes. This redefines the entire construction method of traditional large diameter piles, embracing a design for manufacture and assembly (DfMA) approach for deep foundations. Why change? Our records show that site teams spend approximately 40% of their shift waiting for ready mix concrete. More importantly, challenges on site result in large diameter pile concrete pours taking place late in the afternoon, often overrunning beyond the allocated working hours. This nuisance impacts social communities and repeat occurrences can fatigue the site team. The precast pile construction method mitigates these risks.
METHOD OF CONSTRUCTION Precast low-carbon concrete elements are delivered to site using just-in-time models. The elements are slightly undersized compared with the bored diameter and are stacked from the pile base. A bespoke system is utilised to guide each component into position and also provides the required structural capacity in the permanent condition. Once assembled to cut off level, the pile is capped and grout is placed between the precast outer face and the pile bore to provide the necessary skin friction.
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2
3
3
PRECAST PILE SEQUENCE 1. Pile drilled using conventional rotary bore techniques 2. Undersized precast pile elements are stacked within bore to the correct level 3. The hollow void is protected eliminating the need for pile breaking 4. Fresh grout forms the bond between the precast elements and the bored shaft The Precast elements can be combined with the impression tool enhancements to pile shaft friction, providing increased surety for the quality of construction and thereafter affording greater confidence that the piles can be re-used in the future. 14
Keltbray | HIPER® Pile Overview
1
2
Well controlled environments within off-site manufacturing facilities are well suited to low carbon concrete technologies. This further enhances the benefits of the overall HIPER® product as an environmentally friendly, high quality, low risk product.
Unrecorded process waste accounts for 29% of all costs associated with errors across the construction industry. Expedition Engineering, 2016 8
Captions: (1) Base unit installation and (2) Precast hollow units
BENEFITS Precast pile construction methods offers the following benefits by: 3
Eliminating the need for traditional fresh concrete and reinforcement deliveries Improving productivity by reducing the time taken to concrete large diameter piles Minimising construction waste as piles are built upwards, not broken down to cut off level Improving health and safety by eliminating the need to break piles down
1. Precast caps designed to connect onto Precast piles to accelerate follow on works packages 2. Hollow precast segments of varying lengths and diameter to ensure pile is constructed to the required cut off level 3. Bespoke base unit with grout outlet ports
Improving quality through manufacture of the pile segments in a controlled environment Reducing non-conformances relating to steel levels being out of tolerance Keltbray | HIPER® Pile Overview
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010
ENERGY PILE Harnessing geothermal energy efficiently ELIMINATING THERMAL PILE CONSTRUCTION RISKS
From 2025 new homes will not be built with fossil fuel heating” Future Homes Standard, 2019 9
The international energy agency (IEA) predicted growth of geothermal power generation capacity to grow 3,600 to 4,500MW over the period of 2018-2023 at an average annual growth rate of 4.7% (IEA, 2018). The UK Government’s Ten Point Plan (BEIS, 2020) aimed for 600,000 heat pump installations per year by 2028 to support the drive to save “71MtCO2e between 2023 and 2032”, however only around 30,000 are currently being delivered. 10 16
Keltbray | HIPER® Pile Overview
Ground source heat pumps use low grade thermal energy to heat and cool residential and commercial structures, and balance on and offpeak demand. However, despite being an obvious renewable energy solution, thermal piles are not widely adopted across the UK.
WHY IS THIS? The construction of thermal piles in the UK is a fragmented and poorly managed process, with numerous interfaces presenting significant risks throughout. Considerable damage to thermal loops routinely occurs during the pile trimming process often resulting in delays and the need for costly remedial works. Concrete is also a poor conductor of heat which is ideal for insulating our homes. However concrete is undesirable for thermally active piled foundations as efficient thermal conductivity between the surrounding ground and heat exchangers embedded within the pile is vital to increase the heat pump efficiency and reduce operating cost.
THE SOLUTION Novel renewable energy solutions are urgently required to reinvent outdated global, national, and local networks. The HIPER® pile delivers a new, world-leading, integrated foundation system; meeting short, medium and long term sustainability objectives. Field tests have demonstrated that HIPER® Energy piles significantly outperform the conductivity of traditional solid thermal piles by over 60%. The void filled with water enhances thermal performance and reduces the thermal resistivity of the heat exchangers within the pile. HIPER® Energy piles also focus on resequencing the works to minimise trade crossover and eliminate the risk of damage. Conventional thermal loops are only installed in the Hollow pile void after the piling and groundworks activities have concluded. Therefore the installation, testing and commissioning are completed within a single visit and are removed from the critical path. In addition to the thermal energy generation potential, The HIPER® Pile also offers sizeable thermal storage capacity to manage on and off-peak demand. The sheer storage capacity means thermal energy generated within a single building can be shared across a district network, as well as also offering sufficient buffer capacity as the temperature changes throughout the seasonal cycles.
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Buildings can already produce more energy than they consume. We are working with the UK’s Active Building Centre on the integration of HIPER® pile solutions into the next generation of net zero, energy plus building structures.
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500%
Typical GSHPs are 400-500% efficient, undisruptive, durable and recycles heat energy, compared with ASHPs which have 300% operational efficiency.
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1. HIPER® Energy pile void being filled with water 2. Heat exchanger system within Energy piles 3. Energy piles group loop array
30m deep Hollow Pile (drilled - external / void diameter, mm)
Upper Bound capacity Peak Output (KW)
Lower Bound Peak Output (KW)
Estimated Additional geothermal capacity per m depth
Construction Output (piles per week)
750 / 350
3.70
3.20
0.143 – 0.165kW
25
900 / 500
4.50
3.90
0.184 – 0.213kW
20
1200 / 800
6.00
5.20
0.271 – 0.313kW
15
1500 / 1100
5.65
7.54
0.371 – 0.429kW
10
1800 / 1400
7.86
9.10
0.483 - 0.558kW
8
2100 / 1700
9.22
10.65
0.608 – 0.703kW
6
2400 / 2000
12.20
10.70
0.746 – 0.862kW
4
Two 900mm diameter HIPER® piles provide the equivalent heating & cooling output as a single 200m deep geothermal borehole. The construction of one deep geothermal borehole takes approximately 2 days, whilst one 900mm diameter HIPER pile can be completed within 2 hours.
Keltbray | HIPER® Pile Overview
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REUSE From linear to circular economy A FULLY ACCESSIBLE, ASSESSABLE AND EXTENDIBLE PILE, DESIGNED WITH REUSE IN MIND
On congested inner-city development sites, where land is highly valuable, construction programmes are tight and vehicle movements are restricted, existing piles should ideally be incorporated in the new scheme. However, the quality of historic records, the time at which existing piles can be surveyed combined with attitudes towards risk and warranty often prevent the reuse of existing piles. Existing piles are now frequently removed; adding time, considerable cost and ground risk to a project. Worse still these existing piles, once removed are routinely replaced with deeper or larger diameter piles, often coinciding with the original pile position.
THE HIPER® PILE ALLOWS: 1. Pile reuse owing to the ability to inspect and survey the piles during building occupancy; 2. Standardisation of building layouts to support DfMA approaches; 3. Transmission of wireless monitoring pile performance data to support the structural assessment; 4. Access to increase the pile length at a later date to accommodate larger loads. HIPER® piles may now be viewed as a significant asset for future schemes rather than a potential hindrance to scheme redevelopment, saving time, cost and reducing risk.
Our aim is to offer a use and reuse warranty to our clients at the point of installation.
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Keltbray | HIPER® Pile Overview
The HIPER® Pile is suitable for any function where space is at a premium. The value offered to our clients is multiplied through the multifunctional use, reuse and potential to enhance capacity for future generations. Keltbray | HIPER® Pile Overview
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Uses beyond piling applications The HIPER® Pile void provides a unique opportunity to exploit additional value. Some possibilities include: RAIN WATER ATTENUATION AND STORAGE: The pile void can store large volumes of rainwater to meet the design weather event requirements with added drainage functions. This eliminates the need for excavations associated with installing large attenuation tanks. Therefore, no temporary works or additional retaining wall structures are required, shortening programme durations and reducing project costs.
BATTERY STORAGE: HIPER® Piles can be constructed adjacent other renewable energy hubs such as solar and wind farms, collecting and storing surplus energy. The void may be viewed as a “chamber” of considerable volume and are rapidly installed with conventional piling techniques, compared with excavation methods which require extensive temporary works support. Incorporation of efficient technology such as Phase Change Materials further enhances the energy storage potential.
CONTAMINATED MATERIAL STORAGE: The cost of transporting, treating and disposing of contaminated soil is excessive. Large numbers of vehicle movements contributes to road congestion and the stockpiling of contaminated material impacts on local communities. The HIPER® Pile void provides developers the unique opportunity to storage these materials on site to significantly reduce the volume of material taken off-site for treatment.
THERMAL STORAGE FOR DE-ICING INFRASTRUCTURE: HIPER® Piles constructed adjacent to or beneath critical infrastructure can be connected to ground source heating. A network of HIPER® Energy piles provides the system capability to ensure that critical infrastructure such as road, airports, train lines, and port infrastructure remains serviceable throughout the year, mitigating the risk of delays to end users.
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Keltbray | HIPER® Pile Overview
Keltbray | HIPER® Pile Overview
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Case studies Case study analyses have been completed on three commercial contracts. Each project required low grade heating & cooling systems, however these systems were either proposed through air source heat pumps (ASHP) or ground source heat pumps (GSHP) using 150-200m deep thermal boreholes and/or conventional solid thermal piles.
Project
Case study 1: Small scale office scheme, London
Scope
40no 900dia piles Traditional solid vs HIPER® Piles
HIPER elements
Hollow
Piling / Thermal borehole Programme savings
Carbon saving tCO2e *
Concrete volume saving
Cost saving
25%
55%
32%
10%
21%
46%
65%
10%
32%
54%
45%
0%
Impression Precast Energy Reuse
Case study 2:
47no 1800dia piles
Hollow
Large scale commercial scheme, London
traditional solid vs HIPER® Piles
Impression
Case study 3:
500no 750dia traditional solid
Large scale infrastructure scheme, London
Energy Reuse
vs. 260no 1200dia HIPER® Piles
Hollow Impression Energy offered as added value to client
*NB: Carbon savings do not take into account reuse or operational carbon savings from the use of the thermal void.
Case study 1 SMALL SCALE TEMPORARY STRUCTURE, LONDON The original scheme comprised straight shafted 900mm diameter piles to support a relatively small scale temporary structure. The structure was designed to provide significant amounts of heating and cooling throughout the day and initially proposed the use of ASHP systems located on the roof structure. Keltbray worked closely with the Main Contractor and Client to develop a practical value engineered solution using the full HIPER® Pile suite of innovations. Key benefits from this study are:
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Keltbray | HIPER® Pile Overview
1. HIPER® Piles were on average 20% shorter to resist the original structural loads. 2. Impact of the ASHP system was largely eliminated, with 100% of the heating and 80% of the cooling loads supplied by the HIPER® Energy Pile solution. 3. Overall programme shorter by 25% compared to the solid pile scheme. 4. A reduced number of vehicle movements was positively received by the Local Authority. 5. Annual energy consumption savings of approximately 20% are achievable compared with a gas-fired boiler heating solution.
Works are currently undergoing final design before a start on site in summer 2021.
Case study 2 LARGE SCALE COMMERCIAL OFFICE, LONDON The original scheme, constructed in 2016 with works completed for Principle Contractor, Mace, comprised 47no 1800mm diameter piles, 39m deep. Each pile was constructed with traditional geothermal heat exchanger loops attached to the cage, extending to the toe of the pile, and were installed during the pile installation works.
Keltbray team installing traditional geothermal loops within the solid piles
This project was retrospectively analysed to quantify the benefits of replacing conventional solid piles with HIPER® Piles. A value engineered solution was developed incorporating all in-situ elements of the HIPER® Pile using temporary works liners to form the 1300mm void, and the results are presented in the table below:
Conventional as-built pile
HIPER Pile
1.8 : 0
1.8 : 1.4
Bored : Void Diameter
Benefit
Average Bored Length
39
36
8% saving
Average Concrete Length
28
25
11% saving
Nodule Volume (m3)
0.18
Total Volume Muck Away (m )
5131
4736
8% reduction
571
527
8% reduction
3349
1181
65% reduction
447
158
65% reduction
1018
685
33% reduction
190
65
66% saving
34
27
21% saving
Energy Generation (MWhrs/yr)
1650
3253
97% increase in capacity
EFFC CO2 calculation (tCO2e)
1100
590
46% reduction
Total Muckaway Vehicles Total Concrete Volume (m3) Total Concrete Vehicles Total Vehicle Movements Steel Tonnage Piling Programme Days
Comparison between the as-built piling package and a HIPER® Pile value engineered
100% 90% 80%
23% reduction
70%
35% reduction
60% 51% reduction
50% 40%
67% reduction
30%
66% reduction
73% reduction
20% 10% 0% Muckaway (m3)
Concrete (m3)
Combined tCO2e HIPER Pile Solution
Steel Tonnage
Vehicle Movements Programme Days
Solid as-built pile
Percentage improvements of a HIPER® Pile value engineered solution compared to the as-built piling scheme
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Case studies
Case study 3 LARGE SCALE INFRASTRUCTURE PROJECT, LONDON The original scheme comprised 500no small diameter straight shafted 750mm diameter piles to support a large infrastructure. On average, pile lengths were 30m, however the site was relatively constrained and required the installation of over 100no deep geothermal boreholes. A 1200mm diameter HIPER®
Pile solution was developed comprising half the number of the conforming 750mm diameter bored piles. This scheme provided significant savings on carbon, programme and concrete volume. Although this scheme did not present a cost saving on the piling package, the project was significantly de-risked by
eliminating all boreholes, and the programme implications for the follow-on works were considerably attractive. This case study also offered an opportunity to appraise the impact of replacing some multiple small diameter piles within a single cap, with a single larger diameter HIPER® Monopile.
20000
Pile structural capacity (kN)
18000
1no 2400dia HIPER monopile
16000
1no 2100dia HIPER monopile
14000
1no 1800dia HIPER monopile
12000
750dia
1no 1500dia HIPER monopile
10000 1no 1200dia HIPER monopile
8000
600dia
1no 900dia HIPER monopile
6000 4000
450dia
2000 0
1
2
3
4
5
Number of small diameter piles per cap
Pilecaps with multiple CFA piles vs HIPER® Monopiles It has become standard practice across the industry to select the most economic solution based on unit price. This often means excessive numbers of small diameter CFA piles are constructed, with as many as six piles incorporated within a standard arrangement pile cap. It is known that 600mm diameter CFA piles provide the most cost effective, linear value for the structural load carried and are typically installed on residential schemes. Construction of the pile cap impacts the overall project programme, muckaway and raw material vehicle movements as well as quality and the health and
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Keltbray | HIPER® Pile Overview
safety risks related to HAVS from pile trimming. A large diameter HIPER® Monopile eliminates the need for multiple piles, pile caps and optimises the volume of concrete within the foundation package. An analysis presented in the graph below introduces a single HIPER® Monopile, comparing the structural capacity with that of multiple small diameter CFA piles. For example, a single 900mm diameter HIPER® Pile, using 0.43m3 concrete per linear metre, has the same structural capacity as four 450mm diameter CFA piles, which consume 1.13m3 concrete per linear metre. This gives a 60% saving on concrete and accelerates programmes owing to significant reductions in pile numbers, volume of pile trimming, cap
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Structural capacity of multiple small diameter piles within a conventional cap, compared with a single HIPER® Monopile
construction, and spoil and raw material movements. Similarly, one 2.1m diameter HIPER® Pile gives greater structural capacity than five 600mm diameter CFA piles, giving a 15% saving on concrete volume consumption. This analysis presents one facet of the benefits of larger diameter HIPER® Monopiles. However, additional benefits can be coupled with this foundation solution; such as enhancing thermal energy heating and cooling capacity to improve the advantages of the overall scheme. This, allied with the fact that, following future investigative survey works, large diameter HIPER® Piles can easily be incorporated within future schemes and are therefore fully reused as intended.
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HIPER® Pile Benefits The HIPER® Pile plays a key role in the decarbonisation of UK construction in the short, medium and long term.
THE HIPER® PILE PROVIDES PRIMARY BENEFITS INCLUDING: – Productivity enhancements of up to 30% – Enhanced thermal conductivity of over 60% compared with traditional solid thermal piles – Tangible method of reducing long-term operational carbon related to new buildings – Improved shaft friction of up to 40% – Concrete material savings of between 30 & 70% (pile diameter dependant) – Embodied carbon savings of up to 80% – The ability to reuse, extend and re-warrant
ADDITIONAL BENEFITS TO OPERATIONAL STAFF AND THE WIDER COMMUNITY INCLUDE: – Reduced vehicle movements during construction and decommissioning – Improved air quality owing to fewer vehicle movements – Improved health and safety for site operatives owing to simplified, lean construction processes – Improved quality management to avoid programme delays – Resequencing of works and package management to reduce contractual risk – Mitigation of ground risk for future developers as piles can be reused Keltbray has a total of five patents pending on a suite of fully integrated HIPER® Pile inventions and are the exclusive license partners of the Hollow pile from City, University of London. 26
Keltbray | HIPER® Pile Overview
In conclusion The HIPER® Pile was developed by critically reviewing the inefficiencies, challenges and risks faced in the deep foundations industry. Refined processes, sustainable materials and newly available technology have been combined to present significant additional value to our clients, society as well as the potential to decarbonise construction in the UK and beyond. The developments comprise a suite of engineering enhancements; some of which can be adopted in isolation whilst others are interconnected.
By rethinking standard construction processes, the HIPER® Pile presents a low carbon, productivity enhanced foundation solution, integrating thermal potential whilst extending the applicability of whole life cycle models across the entire construction industry We would be pleased to provide early stage advice for the integration and adoption of HIPER® Pile elements on your projects and to develop truly value engineered, bespoke solutions. If you would like to learn more about the HIPER® Pile and the development process CPD sessions are available on request.
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Acknowledgements The HIPER® Pile developments were funded by UK Research and Innovation as part of the Industrial Strategy Challenge Fund, through the Transforming Construction Challenge programme. Funding for a Knowledge Transfer Partnership was supported by Innovate UK.
The product gratefully acknowledges the support and participation of its consortium members and associates:
Arup Geotechnics City, University of London Converge DB Group (Holdings) G-Core Ltd Access to trial sites during the development was provided by:
Landsec Mace Berkeley Homes
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Keltbray | HIPER® Pile Overview
References
1. ICE, 2020, State of the Nation Report: Infrastructure and the 2050 net-zero target. Available at https://www.ice.org.uk/ ICEDevelopmentWebPortal/media/Documents/News/ICE%20News/ State-of-the-Nation-2020-Infrastructure-and-the-net-zero-target.pdf . Accessed 05/03/2021 2. IPCC, 2018: Framing and Context. In: Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above preindustrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty. In Press. Available at https://www.ipcc.ch/sr15/chapter/chapter-1/ accessed 06/05/2021 3. United Nations, 2015. Sustainable Development Goals: 17 Goals to transform our world. Available from https:// www.un.org/ sustainabledevelopment/sustainable-development-goals/ 4. Construction 2025: industrial strategy for construction - government and industry in partnership. 1st ed. [ebook] London: Department for Business, Innovation & Skills (BIS). Available at: https://www.gov.uk/ government/uploads/system/uploads/attachment_data/file/210099/ bis-13-955-construction-2025-industrial-strategy.pdf [Accessed 13 March 2017]. 5. BEIS, 2021. UK enshrines new target in law to slash emissions by 78% by 2035 Available at https://www.gov.uk/government/news/uk-enshrinesnew-target-in-law-to-slash-emissions-by-78-by-2035. 6. Ritchie H and Roser M (2020) CO2 and Greenhouse Gas Emissions. Our World in Data, Oxford, UK. Available at https:/www.ourworldindata.org/ co2-andother-greenhouse-gas-emissions (accessed 20/11/2020)] 7. LDSA, 2017. Foundations; Guidance Notes for the Design of Straight Shafted Bored Piles in London Clay. LABC, UK 8. Expedition Engineering Ltd., 2016. Get It Right Initiative; Improving value by eliminating error. Research Report, Revision 3 – April 2016. Available at https://getitright.uk.com/live/files/reports/3-giri-researchreport-revision-3-284.pdf accessed 22/03/2021 9. Ministry of Housing, Communities and Local Government, 2021. The Future Homes Standard: 2019 Consultation on changes to Part L (conservation of fuel and power) and Part F (ventilation) of the Building Regulations for new dwellings. Available at https://assets.publishing. service.gov.uk/government/uploads/system/uploads/attachment_data/ file/956094/Government_response_to_Future_Homes_Standard_ consultation.pdf accessed 12/03/21 10. BEIS, 2020. The ten point plan for a green industrial revolution, Policy paper. Available at https://assets.publishing.service.gov.uk/government/ uploads/system/uploads/attachment_data/file/936567/10_POINT_PLAN_ BOOKLET.pdf
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Keltbray | HIPER® Pile Overview
Work with us to incorporate these elements in your project at an early stage of design. FOR FURTHER DETAILS CONTACT: Stuart Norman
Managing Director
Asha Panchal
Technical Manager
Asha.Panchal@keltbray.com
Chris Beynon
Estimating & Design Manager
Chris.Beynon@keltbray.com
Stuart.Norman@keltbray.com
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INNOVATION IN ENGINEERING
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