The ExCeL exhibition centre in London underwent a second phase of development to expand its facilities. This included constructing new North and South Halls and lorry ways totaling over 27,000 square meters. Post-tensioned concrete slabs between 240-300mm thick with deep beams were used. Over 16 weeks, BBR installed their bonded post-tensioning systems to strengthen the large slabs, meeting requirements for strength and fire resistance. The expansion increased ExCeL's capacity to host major international events.

1. EXCEL, LONDON, UK
International showcase
E
xCeL London represents a £150 million investment in the
exhibitions industry. The recent second phase of development has
pushed ExCel London to around 100,000 m2 of flexible flat floor
exhibition and conference space. Richard Gaskill of Structural Systems
– the BBR Network Member in the UK – describes this huge development.
ExCeL London is an international events and In addition to the vast halls totaling
conference centre, located in the Royal 65,000 m2, there are five on-site hotels
Docks, which hosts a variety of events from catering for budget and luxury clients, which
high profile exhibitions and conferences to provide 1,500 rooms, plus over 90 fully Hall. As part of their specification, they had
international association meetings, award serviced apartments, 45 meeting rooms and indicated that all strands should be 15.7 mm
ceremonies and sporting events. In 2012, the 3,700 on-site parking spaces. seven wire super-grade with a minimum
venue will host seven Olympic and five We teamed up with concrete construction breaking load of 279 kN.
Paralympic events. specialist P.C. Harrington Contractors, who Concrete strength was specified as a
This second phase of development was a had commenced a 47-week contract which minimum of 40 MPa and the design
further massive investment focused on included the groundworks, drainage, pile caps accommodated a one hour fire rating
providing superior world class event facilities and structural concrete for construction of requirement. Each hall was separated into
in London, as well giving added support to the new North Hall and lorry way, as well as pours – with the North Hall having 10 and
the capital’s ambition to host an ever the South Hall, lorry way and ramp. the South Hall 12. The lorry ways were split
increasing number of high profile domestic The scheme was designed by main into a further three and four pours
and international shows. This international contractor Sir Robert McAlpine’s in house respectively. The slab was nominally
events venue – now valued at around £300 design team who indicated a PT density of 240 mm thick, with 475 mm deep beams
million in total – is the largest and most 30 kg/m3 for North and South Lorry ways – which covered approximately 65% of the
versatile space in London. and 25 kg/m3 for both the North and South scheme – at centers ranging from 7.8 m to
10.5 m and a 600 mm deep beam at one
end. Pours 3, 6, 9 and 12 were
270 mm thick on the North Hall and
300 mm thick on the South Hall, with all of
these areas being adjacent to the lorry
ways. The area of the halls and lorry ways
together totaled 27,689 m2.
During our 16 weeks on site, we installed
our CONA flat 206, 306 and 406 bonded
post-tensioning systems. Internal pans, where
TEAM & TECHNOLOGY
OWNER ExCeL London
MAIN CONTRACTOR Sir Robert McAlpine
TECHNOLOGY BBR CONA flat
BBR NETWORK MEMBER
Structural Systems (UK) Ltd
44 CONNÆCT

2. BIW HOTEL, KINGDOM OF BAHRAIN
BUILDINGS
“ THE SLAB WAS NOMINALLY
240 MM THICK, WITH 475 MM DEEP
BEAMS – WHICH COVERED
Fast and five star
APPROXIMATELY 65% OF THE SCHEME
... ” B ahrain Investment Wharf (BIW) is a joint venture
between the Bahrain Government and Al Khaleej
required, were installed along each side adjacent to the lorry way to Development Company (Tameer). Roland Zachar, Design
allow post-tensioning to take place. Manager for BBR Network Member NASA Structural
The project has provided much-needed additional exhibition and Systems LLC, reports how they have helped to develop
conference space, as well as a 5,000 seat semi-permanent auditorium the wharf by post-tensioning the floor slabs of the new
at this venue. One of the more unusual features of the construction five star BIW Hotel.
process was that – after completion of the column pile caps – the The master plan of the US$2 billion BIW project is divided into
main contractor erected the steel frame and roof, while the four major sectors – an industrial park, business park, residential
suspended post-tensioned floor slabs for the exhibition halls and and service areas – totaling 1.25 million square meters of
lorry access way were constructed afterwards. Among the challenges rentable area. BIW is strategically located – near to Bahrain’s
during our construction period was the need to maintain access for International Airport, the Seaport, the highway leading to the
maritime exhibits during the London International Boat Show! l causeway linking Bahrain and Saudi Arabia, as well as the newly
proposed causeway between Bahrain and Qatar – for ease of
import and export of goods.
Given the significant overall length of the project, each level of the
Local insight: Docklands hotel was divided into three pours by the inclusion of expansion
joints. All 13 levels above the ground were designed as post-
tensioned flat slabs using the BBR CONA flat system with 305 and
505 anchorage sizes. The lower, more heavily loaded levels,
consisted of 220 mm deep post-tensioned flat slabs, whereas slab
depths of only 200 mm were required for the upper levels.
The majority of projects in the Middle East over recent years have
been carried out at a much faster pace than is typically experienced
in Europe. The period between signing the contract, finalizing the
design, mobilizing on site and pouring the concrete can be limited to
a matter of days – and this BIW job was a prime example. A price
he ExCeL exhibition centre sits close to the Isle of was agreed with the main contractor on Thursday, the letter of
T Dogs, in the heart of an area defined by its seafaring
and trading past. Although hard to imagine now, London
intent received on the following Saturday – and the first pour at
ground floor level was cast within a 10 day period.
Docklands was once a hive of activity, fuelled by the The whole project progressed at a similar pace – with all
arrival and departure of ships transporting goods from 21,000 m2 of post-tensioned slabs designed, installed, poured and
all over the world. The docks here grew up primarily in stressed in less than five months from us receiving the go-ahead on
the early 1800s, with later additions in 1880 and 1921. the project. In recognition of our excellent service during the
works, the contractor awarded us the design and installation of
l
However, by the 1970s, commercial shipping consisted
mainly of container ships which required deep water post-tensioned slab for the associated multi-functional hall.
berths. Thus, the old docks progressively fell into disuse
until the vision of regeneration was born in the 1980s. TEAM & TECHNOLOGY
Now, the shining Canary Wharf development – during OWNER Bahrain Investment Wharf
which Britain’s tallest building was constructed – stands MAIN CONTRACTOR Al Namal Construction Co.
as a beacon for regeneration and has established a TECHNOLOGY BBR CONA flat
second major financial centre in London. BBR NETWORK MEMBER
NASA Structural Systems LLC (United Arab Emirates)
CONNÆCT 45