The stabilization of the huge alluvial deposit on the left bank and the high rock slope on the right bank of the XiaoWan Hydropower Project

摘要

A huge alluvial deposit is located on the left abutment of the Xiaowan arch dam,which hasthe maximum height difference of about 470 m and the total volume of 5.4×106 m3. The natural slope ofdeposit is stable,but the properties and mechanisms of the deposit,as well as the boundary conditions areextremely complicated. Some parts of the deposit near the foot must be excavated to arrange the foundation ofworking machines,the concrete mixing system and the concreting operation platform. The creeping deformationsoccur during the excavating,and then the deformation gradually increases,which shows gradually extendingform down to upward with a drawing model. Based on the dynamic tracing of the developed deformation,a systematic suitable engineering reinforcing treatments is performed,which guarantees the whole stability ofthe huge deposit.