Field instrumentation has been installed to monitor the behaviour of a counterforted diaphragm retaining wall founded in over-consolidated clay during and immediately after its construction as part ofthe A406 North Circular Road, Great Cambridge Road Junction Improvement Scheme in North London. The construction sequence involved installation of the wall under bentonite followed by excavation below temporary props and casting of a permanent reinforced concrete prop slab below the final carriageway level. Measurements of ground movements, total lateral stresses and porewater pressures were made both during installation of the wall and construction of the underpass. The wall itself was instrumented to monitor the development of lateral movements and bending moments. (A)
Abstract