Study of the ground behaviour during deep excavation of a hydropower project

摘要

The study of behaviour of the ground, during deep excavations, cannot be overemphasized. This leads to an appropriate adjustment in the design of foundations, if so dictated for the reasons of safety or economy. The authors have drawn an interesting comparison between the predicted and the monitored rebounds of a 24 meters deep excavation for the power house of a hydroelectric project, in a thick alluvium of fine to medium sands, present in a medium-dense to a dense condition. The prediction of the rebound has been made by the analytical procedure given by Perloff and Baladi, based upon the analogy of a strip excavation. The subsequent rebounds have been measured with a system of the magnetic probe extensometers, having a series of embedded spider magnets.