DDA modeling of the seismic response of large rock cavern complex
The discontinuous deformations analysis(DDA)method calculates large deformations and discontinuous problems using time-step solving,and provides an effective tool to analysis the seismic dynamic response of the rock mass engineering.In this paper,some investigations for the DDA modeling of the seismic response of large rock cavern complex are carried out.First,the existing seismic input methods including the multi-blocks Newmark method,large mass method and large stiffness method are implemented in the DDA program,and the applicability of these methods are discussed.Second,considering the characteristic of the seismic response of large rock cavern complex,a new DDA modeling including a coupling model and a force input method is presented,and can guarantee that the scattered waves are absorbed at both the bottom boundary and the lateral boundaries.Last,the modified DDA program with the new modeling is used for a case study.Simulations of the quasi-static and the seismic dynamic stages for the large rock cavern complex of the Dagangshan hydropower station in Southwest China are carried out.Considering the stress and the displacement after the sequential excavation,the most unfavorable movable blocks are found.Under the strong earthquake,seismic response of the large rock cavern complex can be visually divided into four phases,serious damage of the main machine building and local damage of the downstream side wall of the main transformer chamber are observed,and it is proposed that failures of the most unfavorable movable blocks is an early sign of collapse of the rock cavern complex.
Qian SHENG Xiaodong FU Yonghui ZHANG Jian CHEN
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics,Chinese Academy of Sciences, Wuhan, China
国际会议
The 12th International Conference on Analysis of Discontinuous Deformation(第12届非连续变形分析国际大会)
武汉
英文
61-61
2015-10-16（万方平台首次上网日期，不代表论文的发表时间）