BT award:

Winner

Holger Garden has played a pivotal role in the creation of new technology for the building industry with proven time, cost and practical benefits. A direct result of research in the aerospace and automotive industries, this new technology has now been transferred to the construction industry where it has already made history.

The asset value of the Boots building, where this technology was used, had eroded to zero as a result of corrosion in the steel frame, which was clad in terracotta. The cladding had also degraded, with open mortar joints and terracotta cracking and displacement.

Taylor Woodrow's design brief was to restore the steel beams to a condition 30% better than their original to support a change of use of the building. Garden proposed and managed the application of advanced composites to rehabilitate the beams, taking advantage of materials' mechanical and handling properties for the particular site environment.

Beneath the skin
The building records were so poor that the beam sizes could not be readily identified until the cladding had been removed, by which time overall building refurbishment was well advanced. Any repair solution had to be applied fast to satisfy the construction programme.

Garden demonstrated the lead time for replacing the beams would be 12 weeks but that just two weeks would suffice if the composite solution were used. Taylor Woodrow was awarded the job on a design and install contract. The solution was to apply carbon and glass fibre prepeg composites to the beams by hand as a form of reinforcement.

Prepegs are fibre mats impregnated with resin. This solution was extremely effective and implemented quickly and simply.

The composites are light and strong and offer lower transportation and installation costs than do traditional repairs, high strength and stiffness to weight ratios, shape freedom for moulding as reinforcement around unusual beam profiles, freedom from electrical chemical corrosion, and excellent creep and fatigue behaviour.

Pioneering
This was the first time prepeg composites had ever been used for heritage rehabilitation. Not only was Garden responsible for the research and development of this project, but he went on to manage the work on the Boots site. His biggest management contributions were to propose the composite solution to the various parties, agree the design and install form of the contract and warranty for the materials supply and installation, manage the design team, co-ordinate material supply and installation of site activities, collate health and safety and information for life-time records, and manage all health and safety risks on the contract.

Not content with pioneering this repair method by the use of prepeg composites, Garden is now involved with European norms, writing guidelines and British and European standards for this new construction project.

Congratulations to Garden on a project well done with new technology. The construction industry will be seeing and hearing a lot more of him.

Winner: Holger Garden
Contractor: Taylor Woodrow Construction Ltd
Client: Wheatley Construction Ltd
Contract: Boots Building, Nottingham

also Commended
Darrell Bergesen, Taylor Woodrow Construction; Stephen Evans, Carillion Building; Rod Grinsted, PPT Integration; Peter Turner, Marriott Construction; and Doug White, Wilson Bowden Developments.