The installation of three bridges over the A30 in Cornwall were required as part of a new £90 million bypass through Bodmin. These three bridges were constructed of steel bridge girders with bespoke precast concrete edge beams installed to form the parapets. PCC omnia planks were then installed to form the permanent formwork for the bridge deck.
The pairs of braced girders were delivered to site on specially laden vehicles and were up to 40m in length. MDA and client Kier worked closely during the planning stages of this scheme to ensure that all safety precautions could be installed at the earliest possible stage before the beams were lifted into position on top of the bridge abutments. By installing the combisafe edge protection solution at low level whilst the beams were still on the vehicle lorry, many working at height risks were eliminated.
Once the beams were erected and fixed into position, the MDA team began installing the bespoke PCC edge beams by having a ‘leading edge’ safety protection system in place and removing one section of combisafe, installing the edge beam and then re-positioning the combisafe on top of the edge beam to provide continual edge protection for MDA’s works and for the remainder of the bridge deck works.
The edge beams were lifted into position with a variety of cranes ranging from 90 tonnes – 200 tonnes and provided a perfect straight edge to the bridge and gave each bridge the same sleek look. The omnia planks were then installed creating the permanent formwork for the bridge deck before MDA completed the polysulphide sealing of edge beams and formwork to ensure there were no leaks during the concrete deck pour.
This project was completed on time, with an impeccable safety record throughout some terrible weather conditions. MDA delivered above and beyond the client’s expectations forming a relationship that has continued into the future.