Concrete repairs and high pressure water jetting preparatory works

Cattlelaith Bridge, is a 4 span simply supported agricultural access bridge spanning the M62 near its junction with the A1. The structure was maintained by the client the Highways Agency and their maintenance agent Carillion WSP.

The bridge was suffering from impact damage at a number of locations which had been caused by high vehicles coming into contact with the underside of the bridge.   Topbond previously repaired these impacted sites using High Pressure Water Jetting (HPWJ) and sprayed repair techniques.  However the impact to the outer edge beam was considered by Carillion WSP,  the maintaining agent, to be so severe, that the damaged beam had to be removed from the bridge and be replaced.

To remove the damaged edge beam, the deck had been cut through longitudinally with a floor saw and the damaged beam lifted away.  In preparation for the installation of the new beam Topbond were asked to propose a scheme to remove the remaining cantilevered edge of the deck and expose the existing shear reinforcement projecting from the top of the second (now outer) beam. 

Topbond achieved this by using HPWJ to form a slot over the top of the second beam to expose the bent over shear links and the deck reinforcement.  The water jetted slot extended down, between the top edge of the beam and the underside of the cantilevered deck. 

The cantilevered edge of the deck had previously been attached to a crane with strong backs bolted top and bottom.  Once sufficient concrete had been removed, the remaining steel reinforcement was cut through to free the deck, which was then lifted down to a vehicle at road level to be removed from site.  This process was repeated in phases until the beam was fully prepared.

Prior to the installation of the new beam Topbond undertook further sprayed repairs to damaged areas of the bridge.