Working with Multiplex over 4 weeks at Wembley
CAN was appointed to install specialist anchors beneath Wembley Stadium, providing the critical support required for the construction of the stadium’s iconic arch while working within a highly constrained environment.
CAN was appointed to install anchors into concrete basement slabs on the new national stadium at Wembley. This required the design, installation and testing of anchors to carry a 1550 kN working load, with a bond length of less than 2 metres. CAN produced a design proposal using high strength 63mm tendons, fitted with anchor blocks at their distal ends and secured with low-shrink epoxy resin. Because access to the anchor locations was restricted, this severely limited the choice of drilling equipment.
Holes were diamond-cored to an initial depth of 300mm to penetrate the heavy top mat of steel reinforcement. Holes were then extended down to a depth of 2500mm using a lightweight DTH drill mast mounted on a small sled. This utilised the maximum possible depth of concrete without hitting the slab’s bottom reinforcement cage. The drill mast was fitted with a vacuum dust collection system to maintain air quality in the confined space of the basements. Bars were de-bonded and inserted into the resin-filled holes.
Initial extended proving tests were carried out on a sacrificial anchor to ensure that the system, which had never previously carried more than 500kN, could work at treble the load. Bar extension was closely monitored over several extended loading cycles, and following successful completion of testing, work commenced on production anchors.
A total of 12 anchors were installed and tested. Tie bars were then attached to all anchors and extended 35 metres vertically to roof level, where they were connected to the arch stressing saddle. The arch lift was completed on schedule with anchors and tie bars each carrying the required 1500kN load.
