M6 Higher Walton – Under bridge Security Measures
In Higher Walton, the M6 goes over the A675. The existing bridge consists of 13 steel bridge beams approx 2.5M deep spanning onto the bearing shelf at both the north and south abutment.
We were asked by the client to design, fabricate and install ‘bridge security anti-access measures to both bearing shelves. The need for these works was twofold; stop any terrorists tampering or getting access to existing bearings and stop the public loitering and graffiti the steelwork.
Our design consisted of galvanised steel frameworks securely resin fixed to the existing bearing shelves and fitted with 1”x 1” galvanised mesh frames. The framework and panels had to be profiled to suit the existing bridge beams and no connection was allowed to any existing steelwork or soffit bridge deck. A lockable gate was also required at each end of the abutment. All fixings are ‘anti-vandal’ type to discourage access.
Due to nature of the existing bearing shelves/plinths and the varying existing beam sizes/configuration, a total of 28 unique frames were required. Due to this the fabrication and quality control of all these panels was extremely labour intensive. Off-loading and access was done from the M6 northbound hard shoulder with all tools and equipment fed from on site generator. The on site works took 3 weeks to complete.