|
contents | technologies | |||||||||
| Bamtec system for the concrete floor slab reinforcement  Winter weather is a curse to contractors. Anderson Construction, a reinforced concrete frame specialist, has overcome this problem. Using the Bamtec system for the concrete floor slab reinforcement from Hy-Ten in a development for Bellway at Tower Hamlets, they managed to sustain programme momentum to complete the framework on-time. The Christian Street development, known as Space One, comprises multi level blocks with a mixture of affordable housing and high specification apartments, duplexes and penthouses. Ground conditions required the use of augered concrete piles and ground beams, supporting a reinforced frame. Each floor plate was approximately 1000 square metres.Conventional concrete floor construction requires the precise manual placement of reinforcement bars according to the structural engineer's plan. Slow and labour intensive, this process is especially susceptible to delays due to bad weather. The Bamtec system overcomes many of these difficulties by the use of off-site manufactured carpets of reinforcement. Adrian Gibbs, group contracts manager for Anderson's explained, "During September through to February we had some foul weather on this job with many exceptionally wet days. Using the Bamtec system we were able to make the most of the available weather windows and progress the reinforcement installation. Each concrete floor slab was finished in two weeks so the frame could be completed to schedule and without holding up the following trades." The design of the Bamtec reinforcement carpets was closely based on the design of structural engineers SDP in St Albans. The original specifications were reinterpreted by Hy-Ten's design team, taking into account their wider range of reinforcement bar sizes. Hy-Ten has the largest range of re-bar sizes available in the UK, allowing greater precision when specifying reinforcement. Information from the CAD system is fed into Hy-ten's manufacturing process where reinforcement bars of the correct length and diameter are spot welded by robots onto steel tapes in precise sequence. The carpet of reinforcement is then taped and tagged with colour coding to indicate its position within the floor for correct installation. Less need for skilled labour is another important benefit given the high cost and scarcity of skilled operatives, especially in London. Once formwork is in place, the sequence of operation is straightforward. Tric Trac is used for spacing and the first layer of reinforcement carpets is rolled out over this in accordance with the plan. A second layer of reinforcement at 90 degrees to this is then rolled out to complete the lower layer. Prefabricated chairs are then positioned over the base layer to create the required depth before the final layers of reinforcement are installed. Other reinforcement detailing such as the manual placement of sheer bars is then completed before concrete pouring. "Bamtec addresses a range of issues that the construction industry faces," explained Hy-Ten director Richard Webster. "We can reduce skilled labour requirements, provide speedier installation and help contractors overcome setbacks due to weather, unexpected site conditions and a host of other problems. Having a system to speed frame construction provides contractors with a vital ability to get ahead or pull slipping programmes back on schedule." write your comments about the article :: © 2010 Construction News :: home page |