Balfour Beatty's tender price of US$24.4 million for the expansion joint work is some US$8.9 million higher than had been budgeted for, so cost savings or reallocation of funding will be required before the contract can be awarded, said Feta.
Forth Road Bridge chief engineer and bridgemaster Barry Colford said: "We engaged an experienced firm of consulting engineers to estimate the cost of this job, but the disparity between their estimate and the actual bids demonstrates just how unpredictable the costs of carrying out maintenance works on large bridges without major disruption to traffic can be. This job in particular is unique so there's very little to compare it to. The joints we're replacing are the oldest and largest of their kind in Europe and to keep the traffic flowing during the works we've come up with an engineering solution that is a first for a major suspension bridge." Engineers plan to construct temporary "mini-bridges" on the bridge surface to lift traffic over the work areas.
Another announcement made today is that a routine inspection has identified cracks in some of the heavy-duty nuts where the steel ropes holding up the roadway are attached to the main suspension cables. Nine out of a total of 1,888 similar nuts were found to have cracked. Four on the west cable have already been replaced and the remaining five will be replaced over the coming year. FaberMaunsell has been appointed to investigate the cause.
Feta has also reported that the dehumidification project to fight corrosion in the main suspension cables has made significant progress, despite delays caused by poor weather. The majority of work on the west cable above the roadway has been completed and work is progressing on the east cable and the sections underneath the bridge.
