STUDY ON EFFECT OF IN-SITU STRESSES ON PLASTIC REGION INDUCED BY EXCAVATIONS OF UNDERGROUND OPENINGS
地应力对地下洞室开挖的塑性区影响研究

Three-dimensional non-linear analyses are performed for the underground openings of Baoquan pumped-storage power station in Henan province. The influene of the horizontal in-situ stresses on the distributions of plastic zones is discussed. The Drucker-Prager model is used as yielding criterion. A relation among lateral pressure coefficient, material properties and distribution of plastic zone is also derived theoretically. The region for the yielding most likely to take place is found, and the distributions of plastic zones in terms of the lateral pressure coefficient are obtained. The theoretical study is then confirmed by three-dimensional non-linear analyses.