Building response and ground movements induced by a deep excavation

This paper presents building responses and ground movements induced by an excavation using the top-down construction method. The ground surface settlement and lateral wall displacement for each excavation stage,were observed. The displacement performances of the soil were further studied by examining the strain field and displacement vector developing in a soil mass behind the wall. The centre of the vertical-strain concentration area was found to be consistent with the location of the maximum ground surface settlement. For a given distance from the wall, the maximum vertical soil movement occurred at a certain depth below the ground surface. The soil behind the wall had a non-zero volume change during excavation. Both consolidation and soil creep behaviour might contribute towards the volume change of the soil. Factors such as the type of foundation, the size of foundation, the length of the side of the excavation and the shape of the settlement profile may affect the building performance during excavation. Information regarding a building's location relative to the settlement influence zone is helpful in planning building protection measures during excavation.