Wentworth House Partnership
Capability overview 2023/24
Wentworth House Partnership is the civil and structural engineering consultant within Keltbray.
Keltbray is a specialist construction engineering and infrastructure solutions group Our purpose is to redefine the way sustainable development is delivered. Based on our collective experience, we collaborate at the earliest stage to design and self-deliver innovative customer solutions across technically demanding built environment and infrastructure sectors. Working in partnership with our stakeholders, we are actively contributing to economic growth, social advancement and environmental protection.
Wentworth House Partnership | Capabilities overview | 2022
Contents GROUP OVERVIEW
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OUR SERVICES AND SECTORS
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EXECUTIVE SUMMARY
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– Introduction
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– Key people
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– Design capabilities, training and support
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– Case studies
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Wentworth House Partnership | Capability overview | 2023/24
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Group overview
A SUSTAINABLE BUSINESS MODEL
We are focusing our integrated services on solving customers’ engineering challenges in a rapidly changing world. The resilience of the Keltbray model and the commitment of everyone in the business has shown the resourcefulness, agility and above all else, the dedication to the customers we serve and the communities in which we operate.
WHO WE ARE Keltbray is a UK-leading specialist construction engineering and infrastructure services business, offering a range of self-delivered solutions for blue-chip public and private sector customers.
WHAT WE DO Operating in highly-regulated and safety-critical sectors, we are a key player in developing and maintaining Britain’s economic infrastructure and built environment, and in selective overseas markets. Our customers trust us to deliver certainty on their projects – to specification, safely, on programme, within budget and with care for the environment and the communities that host us.
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Our integrated delivery approach is underpinned by the significant investments we are making in the development of our people, our specialist delivery capabilities and our research and development agenda. It focuses our business on engineering innovation and delivery excellence to provide greater value for all our stakeholders.
WHY WE DO IT Our purpose is to redefine the way sustainable development is delivered. Our deep expertise means that we offer standalone and holistic services, to meet our clients’ complex and changing engineering demands to enhance, upgrade and decarbonise their capital assets.
Wentworth House Partnership | Capability overview | 2023/24
HOW WE DO IT Keltbray’s distinctive delivery model is based around a set of complementary capabilities that together constitute the way we go to work to deliver certainty through the smart solutions we provide for our customers.
SCAN TO WATCH OUR FILM
Watch our corporate film to find out what we do and how we are redefining the way sustainable development is delivered.
Our progressive approach seeks to break down the barriers to success inherent in traditional contracting models. Clients need to feel confident entrusting their investments with a delivery partner capable of turning vision into reality. They need to be certain the end result will meet their expectations – and will be completed to the agreed programme, budget and specifications. We believe that our unique delivery model has the potential to address these challenges – and the key to unlocking its benefits lies in deep and trusting client relationships that allow us to engage early on projects as a prerequisite to delivering greater value. It is only when clients and delivery partners – along with designers and others with vested interests – collaborate from the outset, as part of an integrated team, that opportunities for innovation in engineering can be fully exploited.
“Our sustainable business model provides progressive, long-term environmental, social and economic value to the stakeholders we serve”
STRATEGIC CUSTOMER RELATIONSHIP MANAGEMENT Inherent in the way we go to work, is a different kind of client/delivery partner relationship management approach – one based on establishing and maintaining long-term strategic relationships where both parties’ interests are aligned to deliver mutual benefit.
INNOVATIVE ENGINEERING EXCELLENCE We work collaboratively with our clients, supply chain and industry partners to de-risk project delivery and engineer solutions with a high degree of outcome certainty. Our multi-disciplined network of professional engineers can design, contract and supervise sustainable, high performance engineering and construction services in the public and private sectors.
Innovative engineering excellence
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Talented people
INTEGRATED SELF-DELIVERY MODEL
Future-proofed digital technologies, processes and equipment
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Strategic customer relationship management
Financial resilience
Integrated self-delivery model
EM PL O YE
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SUPPLY CHAIN PA RTN ER S
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By drawing on our specialist in-house delivery businesses and directly employed workforce, we have greater control over quality and productivity. It enables us to be more responsive, rectify issues and interface clashes quicker and achieve greater integration across the project phases. This brings an operational focus and intensity to project delivery that is very different to the traditional subcontracting model.
Wentworth House Partnership | Capability overview | 2023/24
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Our services and sectors STRONG OPPORTUNITY PIPELINE Keltbray is positioned strongly in its chosen markets to take advantage of the visible opportunities and deliver stakeholder value.
Industry-leading business services
Keltbray operates an integrated construction engineering and infrastructure services business model. This is proving highly effective in diversifying our income streams across targeted sectors, locations and different phases of the value chain, helping to deliver a sustainable performance over the longer term.
MACRO-TRENDS Built Environment
Growth in building activity is forecast to pick up in 2023 and beyond, despite tighter monetary policy putting pressure on borrowing rates. The large backlog of work will help to mitigate the impact on building construction work done over 2023 and 2024. Supply-side constraints will subside and construction costs will re-base at a higher level. This correction in the mismatch between supply and demand will ease the pressures driving construction cost growth. Less carbon-intensive demand will also push investment levels and ramp-up activity over the next decade in the UK building and refurbishment market where Keltbray is well positioned.
Infrastructure
Outlook is positive and has been boosted by the government’s £650 billion National Infrastructure strategy, providing the highest levels of economic investment in our industry for decades. This has been further boosted by the Government's commitments to nuclear and renewable energy infrastructure investment to decarbonise the UK generation fleet and increase security of supply in an increasingly uncertain world. This will see civil engineering be the fastest-growing sector in the construction market.
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SPECIALIST ENGINEERING AND ENVIRONMENTAL SERVICES – Demolition and remodelling – Geotechnical engineering and deconstruction – Environment – Contaminated soil / ground water – Asbestos removal – Site remediation – Decommissioning and hazardous waste management
CONSTRUCTION SERVICES – Engineering design – Wentworth House Partnership – Civil engineering – Piling – Sub and super structures – Transport piling – Transport structures
Wentworth House Partnership | Capability overview | 2023/24
INFRASTRUCTURE SERVICES – Rail systems design – Wentworth House Rail Systems – Rail civil engineering – Rail overhead line electrification and distribution – Power transmission – Energy network distribution – Renewables – Highways civil engineering – Energy storage – Primary and distribution substations and telemetry
SUPPORT SERVICES – Preconstruction and commercial management – BIM and digital engineering – Civil engineering plant, lifting and haulage equipment – Project delivery support services: – Recruitment – Operational safety training – Occupational health and wellbeing
Dynamic growth sectors
Through our UK business network, Keltbray has a strong and growing presence in built environment and infrastructure sectors. Our business activities are shaped by the product innovation and delivery certainty of the services we provide to meet clients’ sustainable development challenges.
gineering and t en tal services s i l en ia ec ironm p v S n e
s on cti rvice tru se ns ring Co ee in
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nf r ee astr rin uc g s ture erv ices
Integrated self-delivery
I in g n e
Lo gis tica l serv support ices
Building
Energy
Rail
Transport
– Residential/ Commercial – Manufacturing – Industrial
– Civil Nuclear – Power Networks and storage – Renewables
– UK Network – Urban Transit – High Speed 2
– Highways – Aviation – Marine
Government infrastructure – Defence – Health – Law and Order
Public Utilities – Telecoms Networks – Urban realm and regeneration – Flood alleviation
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Wentworth House Partnership | Capability overview | 2023/24
Executive summary
Wentworth House Partnership Ltd (WHP) is a leading and innovative civil, structural and geotechnical engineering consultancy, providing design and checking services across all built environment sectors and industries including both temporary and permanent works solutions. Wentworth House Partnership, under the leadership of managing director Stuart Vaughan FICE MIStructE, is part of the built environment services offered at Keltbray. Employing over 70 engineering professionals, WHP can act as an independent consultant, as well as offering a complete range of multidisciplinary design and build services through Keltbray Group, including: – – – – – – – – – – – – –
Demolition and decommissioning Façade retention, needling and propping Basements – bottom-up and top-down Temporary stability and structural alteration (cut & carve) Tower and mobile crane foundations Gantries and grillages Structural steelwork and concrete Formwork and falsework Ground engineering (piling, earth retention schemes) Geotechnical analysis including 3D finite element modelling Historic and heritage structures Asset verification Emergency response engineering
Client drivers – – – – – – –
Efficient optimum solutions Innovation Modern methods Sustainability Collaboration Digital engineering Delivery to meet project programmes
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Introduction Wentworth House Partnership are a well-established and award winning specialist design consultancy, formed in 1999. With a track record for our imagination, initiative and high level of technical expertise, we are now recognised as one of the leading temporary works and geotechnical design consultancies in the UK. Health & Safety is a priority in all of our designs, and our philosophy is to cooperate with the Principal Designer and all other project stakeholders and produce method statements and risk assessments for all major works, ensuring the health and safety of both site personnel and the public. In order to provide the best possible service to our clients, WHP offers a flexible design package to suit individual requirements. We work closely with all parties to provide a personal service and fully understand their needs to achieve a satisfactory design outcome within the agreed programme. With our contractor-based mindset, we are focused on constructability, timely delivery and providing the best value for our clients. Our experience covers all areas of temporary works, refurbishment and foundations in the building and civil engineering sectors in commercial, residential and industrial buildings, including: cofferdams and deep basements, headings, needling, shoring, façade and party wall supports in busy city centres across the country. We also have wide experience of working with Grade I and II listed buildings. Sustainability is one of our prime considerations, and as part of our commitment to reducing embodied carbon we are one of the first temporary works consultancies to commit to specifying low carbon concrete. We have also led research to validate suitability of low carbon concrete, in collaboration with Keltbray Group with applications such as HIPER® Pile. 8
Wentworth House Partnership | Capability overview | 2023/24
Key people GROUP TECHNICAL DIRECTOR
MANAGING DIRECTOR
DIRECTOR OF STRATEGIC ENGINEERING
Craig Moorfield
Stuart Vaughan
Tim Lohmann
BEng (Hons), MIE (Aust)
MEng CEng FICE MIStructE
BEng CEng FICE FIStructE
Sustainable, specialist and innovative engineering services are core to Keltbray’s strategy and in his role, Craig leads the Group’s performance in engineering, research and development and innovation. He is also responsible for the corresponding technical and engineering assurance across the group, providing clients and key stakeholders with confidence in the sustainability of our solutions.
Managing Director of WHP, actively involved in and passionate about delivering efficient design solutions to our projects through focus on working with our clients to provide optimum buildable and safe quality solutions saving our clients time and money.
Tim has nearly 30 years’ experience in delivering and designing temporary works schemes, primarily in complex city centre environments. He started in construction with O’Rourke in the late 1980s and left after 15 years with them in a variety of engineering led roles. He has subsequently worked with an architectural precast supplier, and London based concrete frame contractor. More recently he established and ran a successful temporary works design business before leaving to join Wentworth House in 2015. He has experience of a wide range of demolition and construction techniques.
Craig was previously Head of Engineering for Multiplex Europe and brings a wealth of knowledge and experience gained from working across Keltbray’s core Built Environment and Infrastructure markets. He has led the development of cutting-edge construction methodologies and analysis techniques on some of the world’s most high-profile projects. Craig has an industry reputation as a leading technical expert in the sustainable design and delivery of complex buildings and infrastructure, and he plays a creative role in delivering innovative and sustainable solutions. His experience of successfully developing cuttingedge ideas greatly benefits the Group as it evolves its strategic focus towards expanding the opportunities to deploy Keltbray’s integrated self-delivery model into existing and new markets.
Proficient in a wide range of construction engineering solutions from façade retention, building stability and basement construction temporary works through to efficient permanent works solutions. 12 years main contractor experience delivering coordinated engineering solutions across a range of packages. Member/contributor of CIRIA committees.
Key projects – 100 Bishopsgate/I Bishopsgate Plaza & Devonshire Row – Earls Court Demolition – winner of ICE Coopers Hill War Memorial medal and BCIA temporary works award – K1 Knightsbridge – London Bridge Station Redevelopment, – Thames Tideway Tunnel – East – HS2 – S1/S2 – Nova East – Broadgate Tower – BBC Broadcasting House
Tim has also been chairman of the Temporary Works Forum, a not-for-profit business dedicated to improving the understanding and delivery of temporary works across the industry. He has been a judge for the BCI Awards and has also been instrumental in establishing the Centre of Excellence of Temporary Works and Construction Method Engineering at City University and the publication of a series of papers in The Structural Engineer on temporary works.
Wentworth House Partnership | Capability overview | 2023/24
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TEAM LEADERS
Serdar Dundar
David Kwong
John Laverick
CEng FICE FIStructE MHKIE MSc BSc
MEng CEng MICE
CEng MIMechE FICE
Serdar is a Civil Engineer with a unique balance of consulting and contracting experience from a wide range of major multidisciplined projects in the Civil Engineering and Building Industries. He has 21 years' of international design experience in large-scale infrastructure projects in Eastern Europe, Middle East, Hong Kong, Singapore and Australia.
David, Associate at Wentworth House Partnership, joined in 2011 as a Graduate Engineer. Throughout his tenure, he has gained diverse experience in temporary works and geotechnical design, working with both consultants and contractors on technically challenging projects. He also has expertise in pile designs and various piling construction techniques, acquired during his time at Keltbray Piling.
John is a Director at Wentworth House Partnership and leads our team of engineers and technicians based in Leeds, West Yorkshire. John has over 20 years’ experience successfully executing projects across multiple sectors including nuclear, defence, energy, highways, railway and complex demolition among others.
Recognised as originator of competitive and innovative solutions, combining specialized knowledge from construction in marine environment, construction of cut and cover tunnels and underground stations, construction of precast segmental bridges, longspan steelwork structures.
David's commitment to safety and quality is evident in all his roles, where he has been involved in numerous demolitions, façade retention, cut and carve, deep basement, and piling projects in busy city centres. Notably, he has served as the Contractors Responsible Engineer on significant projects, such as Crossrail West Stations and Museum of London, ensuring smooth operations adjacent to Network Rail interfaces. His contributions to WHP span various capacities, from acting as a Project Engineer on multiple ventures to leading teams of engineers within the organization. Some of his notable projects include London Wall Place, Palace Street, Earls Court demolition,UCL Institute of Neurology, Thames Tideway Tunnel East, HS2, and the HIPER® Pile on behalf of Keltbray Piling business.
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Wentworth House Partnership | Capability overview | 2023/24
John’s mechanical and heavy structural/civil background means he has particular expertise with complex engineering in heavy industries and in particular at the interfaces of disciplines. For instance, heavy craneage or complex lifting schemes, demonstrated by a recent project to decommission a fire damaged and partially collapsed wind turbine structure.
Tomasz Mochol
Surinder Mann
Kostas Leontaridis
MSc CEng MICE Eur Ing
MSc BEng CEng MICE
CEng MICE
Tomasz started his career working in consultancies in Poland on reinforced concrete and steel structure design and with a contractor on glulam design. On joining Wentworth House Partnership in 2006, he quickly adapted to UK codes and the specialities of temporary works design, and is now an accomplished designer with a broad range of temporary works design experience which he uses to good advantage on his client’s projects.
Surinder has led teams in structural design in the UK and US in the onshore and offshore sectors. More recently he has been responsible for the temporary works design in major buildings in the UK. He has extensive experience with onsite coordination and delivery of those projects.
Kostas has an MEng and an MSc from the Aristotle University in Greece and is Chartered with ICE since 2019. He has worked as a geotechnical engineer in Greece for nine years, until he joined WHP in 2017 as a Senior Engineer in Temporary Works, carrying out structural and geotechnical design, managing projects and leading teams of Engineers and Technicians.
Noteworthy projects he was involved in include Earls Court – demolition of existing super and sub structures directly adjacent and above rail tracks and assets, Blackfriars Station – removal of the existing railway station down to the foundations to allow new secant pile wall formation, and K1 Knightsbridge – retention of façades to four elevations.
Surinder offers a command of the requirements of demanding projects with tight deadlines and the coordination of the multiple and diverse parties involved in the construction process. Noteworthy projects include Miller Park baseball stadium permanent works design in Milwaukee and HS2 temporary works design.
His main areas of expertise include retaining structures and propping, deep excavations, slope stability and damage assessment of underground assets. Some of the major projects Kostas has worked on include Thames Tideway Tunnel East, K1 Knightsbridge, Heads of the Valley Road in Wales, xHoly Church of Protato drainage and foundation reinforcement in Mount Athos, Greece, and the design and rehabilitation of the unsanitary Dumpsite ‘Café’ in Montenegro.
Wentworth House Partnership | Capability overview | 2023/24
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TEAM LEADERS (CONT)
Theodore Litsos
Dylan O'Reilly
Michael Allen
MEng MSc DIC CEng MICE
CEng MICE
Lead Technician
Theodore is a Principal Civil Engineer experienced in the design and assessment of infrastructure projects in the UK. He is the team leader of our Bristol office, responsible for business development in South West and the wider UK infrastructure market.
Dylan joined Wentworth House Partnership in 2019 and leads our team of engineers and technicians based in Glasgow, central Scotland. With eight years working in site-based contractor roles, acting in Temporary Works Supervisor/Coordinator roles as well as Appointed Person for Lifting Operations for the duration of his career, Dylan has an in-depth knowledge of the engineering and delivery of reinforced concrete structures, including in situ, precast and post-tensioned, and the associated construction methodologies employed.
Michael is an experienced CAD and Tekla Technician. Primarily working in both steel and reinforced concrete (RC) detailing, he has worked on a variety of projects including RC retaining walls & stairs, precast service trench lids, various sized façade retention systems and steel frames as well as one off bespoke steel frame solutions.
Theo has designed concrete and composite (steel-concrete) bridges, carried out assessment of existing structures and structural inspections during the last decade. He has also successfully managed multidisciplinary projects on HS2 Enabling Works and Bristol Metrobus. More recently, he leads the temporary works design on the A30 Chiverton to Carland Cross project and provides temporary works support to our clients in Hinkley Point C.
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With experience including the delivery of new-build healthcare and education facilities and residential and high-rise structures, he possesses extensive experience in the management and coordination of temporary works from cradle to gate.
Wentworth House Partnership | Capability overview | 2023/24
He has a determination to present WHP information in a clear, concise, and efficient manner; that is easily coordinated with other disciplines and provides our client with the high-quality end product they require. Michael has a strong focus on supporting the CAD team and overseeing the development of all apprentices within the CAD team allowing for the next generation of technicians/engineers to build their full potential.
RESOURCES
Wentworth House Partnership employs over 70 staff from five regional offices: – – – – –
Esher (Head Office) Farringdon (London) Bristol (South West) Leeds (North England) Glasgow (Scotland)
Our workforce is more than
20% female We are multinational, with more than
fifteen nationalities forming our workforce.
Our engineering team, with handson guidance from our managing directors, includes students on year-long industrial placements and undergraduate apprentices, through to the senior team of associates and technical directors.
Design Designcapabilities, training and capability support WHP provide a full range of civil, structural and geotechnical design services for a national and international client base, on projects fees ranging from
£500 to £1m+ Temporary and permanent works design Tender support to main and subcontractors Category 3 independent checking Highways and railways asset protection WHP utilise a wide range of software packages, giving us the appropriate tools for the tasks being undertaken We have a commitment to support the construction industry, including authoring CIRIA Guides, participation/leading the Temporary Works Forum, preparation of British Standards, sitting on ICE editorial panels and judging for BCI & Ground Engineering awards
We have an established graduate apprenticeship programme, where school leavers join the business and we support them through day-release University courses in Civil Engineering. The students bolster their University learning with on-the-job experience and gain accredited degrees, ready to progress toward chartership with professional institutions. WHP has an established & successful training programme for The Institution of Civil Engineers and Institution of Structural Engineers, and mentoring of staff to chartership in one or both bodies.
The engineers design output is supported by our team of technicians who produce the design deliverables using BIM or 2D & 3D modelling as appropriate.
Wentworth House Partnership | Capability overview | 2023/24
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Case studies
Hinkley Point C
Nova East
Wynyard
Energy and infrastructure
Integrated substructure
Emergency response
Hinkley Point C (HPC), is the first nuclear power station to be constructed in the UK since Sizewell B was commissioned in 1995. The project will construct two nuclear European Pressurised Reactors (EPRs), with a combined energy output of 3,200MW. This is estimated to provide around 6% of the UK electricity demand.
The Nova East project is located in Central London, near Victoria Station, and when completed will comprise of a 17-storey superstructure with a basement up to three levels deep. Below ground level the project is constrained by various third party assets including TfL/LUL Victoria Line tunnels, shafts and access links; Thames Water (TW) Kings Scholars Pond Sewer (KSPS) and Western Deep Sewers and associated bridging structures; as well as the existing Nova North building with adjoining basement substructures.
In September 2020, Wind Turbine 6 at Walkway Wind Farm in County Durham caught on fire resulting in extensive damage to the plant. The wind farm has been operational since 2008 and consists of 7 x MM82-2MW Turbines, the facility is owned and operated by EDF Renewables UK.
Wentworth House Partnership (WHP) were contracted to this project as temporary works designers for the various contractors on the HPC site. The majority of WHP’s work has been for the joint venture principal contractor with the provision of a resident engineer acting as temporary works coordinator on their behalf, as well as working directly for the subcontractors. WHP commenced work on HPC in 2020 and to date have provided rebar stability designs and CAT3 checks of the steel liner components for the reactors during the temporary condition.
WHP were involved during the tender June/July 2019 providing consultancy guidance for the contractor’s bid, and then appointed to develop the project proposals with Keltbray's Demolition and Civils/Structures business during a subsequent PCSA agreement period ending December 2019, with main temporary works designs starting in earnest in January 2020. WHP were also involved for the advance works on behalf of Keltbray's Piling business who had already been appointed by Landsec to carry out the piling works for the project, which involved plant load assessments and analysis of the secant pile walls for structural design. WHP provided design solutions for tower crane foundations, steel gantries to support plant, excavation propping, core stability assessments and a ground movement assessment.
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Wentworth House Partnership | Capability overview | 2023/24
Keltbray's Decommissioning business was contracted to partially dismantle the wind turbine by lifting the blades and nacelle plus the uppermost tower section to ground level using a large crane. WHP (acting on behalf of Keltbray's Decommissioning business) were instructed to provide technical consultancy services to the project, and provided designs for working platforms, structural strength during lifting, bespoke storage pedestals, and lifting arrangements for the nacelle and tower sections. WHP also provided specification and supervision for non-destructive testing of the turbine.
Aberthaw
Hurst Castle
Smithfield Avenue
Industrial decommissioning
Emergency response to Heritage
Emergency response to Heritage
Keltbray's Decommissioning business was awarded a contract for the demolition of an experimental Carbon Capture Plant (CCP) located within the Aberthaw Power Station (APS) site. The plant consisting of various low level structures with the addition of four high-level modules each with their own steel frame. Due to the APS site being situated on the coast with access to a docking facility, these high-level modules were constructed off-site and shipped directly from China. Upon arrival, they were lifted whole (steel frame and vessels) into place, where they were then bolted in to base plates which were installed prior.
Hurst Castle is an artillery fort established by Henry VIII on the Hurst Spit in Hampshire, England, between 1541 and 1544. It formed part of the king's Device Forts coastal protection programme against invasion from France and the Holy Roman Empire, and defended the western entrance to the Solent waterway. The early castle had a central keep and three bastions, and in 1547 was equipped with 26 guns. It formed one of the most powerful forts along the coast.
Smithfield Market is a series of structures in the City of London that have historically been home to a wholesale market, namely the General Market, Poultry Market, West Market and East Market, which were constructed between 1866 and 1883. Below these is a cut and cover railway tunnel and sidings, supporting the ground floor and upper levels on a system of wrought iron members and masonry jack arches.
Following the collapse at Didcot, the client had implemented a policy stipulating that any design requiring pre-weakening, must be Category 3 checked. WHP were appointed on this project only for the checking of one design. WHP were tasked with firstly Category 2 Checking the design provided by Keltbray Decommissioning, then by selecting and liaising with a Category 3 Checker. The category 2 check consisted of assessment of the frames as a whole, stability of the structure after pre-weakening and the force required to rotate the modules.
On 26 February 2020, during a storm, a portion of the western wing external perimeter wall collapsed. The client was aware of serious issues with the eastern wing foundations due to undermining as a result of coastal erosion. The collapse in the western wing was in an area showing no signs of structural distress prior to the collapse. WHP designed a temporary shoring system using scaffold with individual geometry to suit each case-mate. The shoring system incorporated a protection deck and protection access routes using ladder beams.
The structures are intersected by three public highways, all of which were covered by a glass roof structure supported by precast concrete purlins and trusses. Works were initiated on this project due to a series of structural collapses on East Poultry Avenue where precast concrete gutters, each weighing approximately 6000kg, failed at their fixing points and fell to the ground on the public footpath below. Keltbray were called in to assist City of London in making the area safe. WHP developed and designed a scheme which allowed for the safe removal of the gutter units. As a preventative measure, a decision was made that the similarly constructed gutters on West Poultry Avenue should also be removed. This was slightly more challenging because the substructure was more susceptible to overloading. Further inspections suggested that the precast concrete roof purlins were also at risk of collapse, requiring WHP to design temporary supports.
Wentworth House Partnership | Capability overview | 2023/24
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Case studies cont.
A30 Chiverton to Carland Cross
Earls Court
8 Bishopsgate
Highways and infrastructure
Demolition
New build, reinforced concrete
The A30 Chiverton to Carland Cross scheme encompasses the construction of a new 8.7-mile dual carriageway which will connect with the existing A30. National Highways’ proposal also includes the replacement of several roundabouts, the construction of new bridges, access roads and junctions, as well as the retention of the A30 for local traffic. The scheme’s objectives are to reduce congestion, connect communities, and improve safety, operation and efficiency.
Earls Court (EC) was an extremely large project in the centre of London, located in a highly residential area with major rail interface. The project involved the demolition of two exhibition centres – EC1 and EC2.
8 Bishopsgate Tower is a new 50-storey mixed-use project being developed in London. It will replace the existing 6-8 Bishopsgate and 150 Leadenhall Street buildings and provide 5,600,000sq.ft of office retail and public space.
WHP was appointed as the Temporary Works Designer by the demolition contractor Keltbray. The high complexity of the project was a result of both structural nature and site constraints, which included London Underground and Network Rail lines and depots, the Empress State Building and the adjoining residents. There were many challenges associated with different aspects of activities involved in this project. From the design point of view they included huge, varied and complex structure of EC1, EC2 and surrounding infrastructure; complex engineering roof temporary works design, varying forms of construction leading to differences in quality and construction type throughout the buildings; Temporary Works undertaken in the vicinity of London Underground and Network Rail possessions.
Keltbray began demolition work at the City of London site in 2018 and continued with piling, construction of substructure and construction of the two towers which form the 24-storey south and 50-storey north cores of the superstructure.
Having been awarded the scheme by National Highways, the Costain/Jacobs partnership has appointed Keltbray to deliver 14 bridge structures. Keltbray will support the partnership in developing and delivering engineering-led structural bridge solutions, maximising the use of modularisation and modern methods of construction to identify and construct standard bridge elements to ensure greater buildability and quality. WHP have been involved in the project both as direct consultants to Costain and to Keltbray, providing Temporary Works structural designs of overbridges, underbridges, precast BEBO arches, and small-span structures. WHP has also provided efficient solutions for the design of crane platforms, slope stabilities, lifting arrangements for heavy items, soil nailed slopes, haul roads, rebar stability and demolition works.
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The design works included over 100 greater and smaller items, from which most important were: Main Roof deconstruction, where 1300T heavy and 126m x 76m in plan and 24m-high truss roof has been re-framed and lowered by 28m; Bridge 19 removal, where a heavy bridge had to be removed in a quick and least-disturbing manner; removal of the heavy RC portal beams over LU tunnels using a ‘super crane’.
Wentworth House Partnership | Capability overview | 2023/24
Over a 3-year period, WHP were engaged by Keltbray to develop detailed design of all the temporary works required from piling stage to the completion of the cores. WHP scope covers a wide range of temporary works including design for temporary hoist bases, access platforms, formwork and falsework, steelwork gantries, complicated embedded plate connections for permanent steelwork, and temporary supports for jump form. In addition to design of temporary structures, WHP carried out stability assessment of the cores during construction stage. This involved structural modelling of the partially constructed superstructure to represent various intermediate stages of construction, verification of the structural strength of core walls, provision of additional reinforcement where required.
Devonshire Row
Belfast
East London project 1
Demolition
Emergency response
Post-construction stability verification
The Devonshire Row buildings comprise 142-150 Bishopsgate and 1-17 Devonshire Row. The buildings date from the 1870's and have a total of four storeys above ground with a mansard roof and one level of basement. London Underground's Metropolitan line runs directly beneath the buildings. As part of the redevelopment and extension of the existing Devonshire Row buildings, Keltbray were awarded the contract for the demolition and the structural alterations package. Subsequently WHP was instructed to undertake the temporary works design.
In August 2018, a fire badly damaged a listed building in the centre of Belfast. This left the perimeter walls standing and the inside largely destroyed. Because of the dangerous nature of the structure, the surrounding area was closed. WHP were involved in developing a scheme to make the remaining structure safe to allow the surrounding area to reopen and to start the rebuilding works on the retained building.
The scope of the works included extensive needling of the existing brick walls, a small section of façade retention, structural demolition (bottom-up), floor assessments and wall propping. Because the existing buildings are directly above the Metropolitan Line, there was requirement from LUL that the load on the tunnel will never differ more than 10% of the original design.
The design approach to the public safety cordon involved the use of empirical techniques, as well as advanced simulation software. The design approach for the façade retention scheme was complicated by the poor ground and buried services, as well as having to allow for installation with no access inside the building. The solution developed by WHP involved the use of shipping containers as structural components, as well as fibre-reinforced foundation rafts. The scheme was successfully installed, and access to the city centre has been reinstated.
WHP were assigned the task of investigating a residential tower in East London for structural deficiencies, and proposing remedial solutions. The 28-storey building is an RC structure comprising of flat slabs and frames, with the lateral stability provided by cores and shear walls. Some of those shear walls do not extend down to the foundation and are interrupted at Levels 01 and 09, where they are supported by two columns on the floor below. The scope of WHP’s work included the analysis of an FEA model of the building to identify the areas of concern, calculate the stress envelopes and propose a strengthening strategy where necessary. Additionally, the slabs underneath the walls and the supporting columns were also examined to identify potential issues. WHP were also assigned the task of designing a temporary works solution to facilitate installation of the permanent strengthening works to the columns. The proposal was to employ a method to temporarily unload the columns on a system of steelwork support frames and hydraulic jacks to allow the strengthening works to be installed.
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Case studies cont.
East London project 2
10 Dover Street
HS2
Structural strengthening with CFRP
Detailing and Drafting
Infrastructure and Rail
A 10-storey reinforced concrete residential building, already constructed, has been re-assessed by a structural engineering consultancy and found to suffer from structural deficiencies. More specifically, an existing 675mm thick transfer slab at the ground floor, which transfers loads from ground-to-first-floor columns to the vertical elements of the upper basement has been identified to have been insufficiently detailed for bending resistance. WHP was employed by the original developer of the structure, in order to develop a carbon fibre reinforced polymer (CFRP) solution for strengthening the affected slab.
A London-based steelwork fabricator approached WHP to procure design of their steelwork when the task was already 50% complete, as the previous engineer had failed to deliver.
HS2 is a new high speed railway linking up London to the Midlands and North of England. Area East Phase S1/S2 is the section north out of Euston Station near the Hampstead Road Bridge. This section of the works involves the exit of the HS2 line from Euston station in a new cut as it heads north.
WHP was assigned the assessment of the ground floor transfer slab, based on an existing global model of the 10-storey, 2-basement RC structure, and the development of a CFRP scheme, applied to the soffit of the slab, aiming to increase the bending strength to resist the action effects, as calculated by the re-assessment. The identification of the defective areas in the building was led by the permanent works structural engineers. WHP provided a due diligence assessment of the stress state of the affected transfer slab and developed a strengthening solution, consisting of applying layers of CFRP plates at the areas of the slab soffit that had insufficient steel reinforcement.
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Dover Street was an existing 6-storey building in Mayfair, London. The owner wished to modernise and make the most of the space available. This would require the existing shell to be retained, but the interior to be mostly rebuilt, with a steel frame supporting composite steel decking. The spatial constraints of the existing building and those around led to a number of interesting connections. The steel member size, location and loads were determined by others, WHP took those and in combination with the architectural constraints developed a fully detailed scheme to allow offsite fabrication and onsite installation of the steelwork required by the scheme. A number of connections had already been designed by the original detailing engineer, these were to be checked for suitability and the connections that remained were to be designed, detailed and fabrication information produced from this. There was a mixture of site fabricated and shop fabricated elements.
Wentworth House Partnership | Capability overview | 2023/24
WHP have been engaged in several temporary works designs such as: working platform designs; sheet pile designs for capping beam construction for secant pile walls; tower crane support frames; checks for surcharges adjacent to existing national rail retaining walls; design of large temporary berms.
This report was written, designed and produced by Keltbray Communications Team. No part of it may be reproduced without the prior permission of Keltbray Holdings Limited.
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SAFE, EFFECTIVE AND INNOVATIVE DESIGN SUPPORT FOR UK CONSTRUCTION
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