The tarmac ramps and hinged covers were put in place to allow work to be carried out at night on the replacement of the expansion joint - before being lowered again in the morning for the rush hour traffic to pass over.
The only problem with this system was the noise created by the cars, lorries and coaches as they clattered over the joint at often more than the regulation 30mph. Residents in nearby flats overlooking the flyover have had to endure months of disturbance as the works have progressed.
Over the last few weekends, the new expansion joint has been installed - during a full closure of the flyover to allow the concrete to set without any undue vibrations. Working throughout the 48 hour weekend closures, day and night teams worked continuously to ensure that the road was ready for Monday morning.
|Installing the expansion joint - at night|
|Aligning and levelling the joint|
The specialist joints allow the bridge to expand and contract with changes in temperature and are made up of two interlocking "combs" that are expected to move by 100mm on each side of the bridge between a cold Winter and hot Summers' day. Movements of 20mm are not uncommon during a single 24 hour period. The teeth maintain a road surface whatever the gap in the concrete bridge underneath.
|The new joint in place|