Over 100,000 Ancon Rebar Couplers were used in the concrete support towers, end piers and road deck of one of the longest cable-stayed bridges in the world at the Queensferry Crossing.
Reinforcing bars which strengthen the concrete deck, towers and end piers had to be reliably, mechanically connected end to end throughout the structure. To perform this hidden, but vital structural task, Bartec Plus Parallel Threaded Couplers were selected from the comprehensive Ancon range. Standard Type A and Type C Bartec Plus couplers, stainless steel BT couplers and Bartec Plus Headed Anchors, were delivered to site in a variety of sizes to match rebar diameters 12, 16, 20, 25, 28, 32 and 40mm, with the three largest sizes being used to join reinforcement running the full height of the three 680ft support towers.
BT stainless steel couplers, manufactured from 1.4462 duplex for optimum strength and increased corrosion resistance, were used to connect stainless steel reinforcing bars in the support towers, below and around the water line to accommodate tidal fluctuations.
Bartec Plus Headed Anchors were used in the support towers to provide an effective and proven method of anchoring the rebar end within the concrete. A headed anchor is essentially an oversized coupler capable of carrying the full tension load of the bar when it bears against the concrete in which it is cast. The Headed Anchor removes the need for a hooked rebar end and subsequently reduces congestion, simplifying bar placement.
Ancon couplers can simplify the design of reinforced concrete, speed up construction and, because there are no lapped joints, reduce the amount of reinforcement required. Furthermore, coupled reinforcing bar is not dependent on the integrity of the concrete and retains its strength if there is any concrete degradation.