A database has been established of the pattern of ground and wall movements measured at sites where bored pile and diaphragm retaining walls were being used for the construction of retained cuttings, cut-and-cover tunnels and deep basements. Results were obtained from a large number of instrumented highway and building schemes in the UK and also, where they are considered relevant to UK practice, from elsewhere in the world. The variation of surface ground movements with distance during wall installation and bulk excavation are separately reported. The zones of movement which develop are related to the type of wall construction, the ground conditions and the stiffness of the support system used during excavation in front of the wall. The results are of value both in establishing the most probable movement and acceptable limits when using the Observational Method to control construction and also in assessing the effects of construction on neighbouring buildings and buried services. (A)
Abstract