Study On The Failure Modes And Process Of Typical Collapse In Yushu, Qinghai-tibet

Tibetan Autonomous Prefecture of Yushu, northwest China’s Qinghai Province in the hinterland of Qinghai-tibet plateau, the boundary between balyanlkalla plot and qiangtang block near the jinsha river suture zone. Geological environment is very complex, collapse disasters occur frequently, caused and potential collapse disasters have been a serious threat to personnel and property safety. Therefore, study on the rules for reservoir develop distribution and the failure modes and process of collapse, will has guiding significance for the prevention and harnessing of the collapse disaster.Firstly, through field investigation, this paper collected field and indoor data, according to geological environment background of research area, analyzed the types of collapse disasters in the area; studied the forming conditions and influence factors of collapse disasters; summarized the developmental characteristics of collapse disasters. Think that internal factors such as topography and geomorphology, rock and soil body types play a control role in slope disaster development, external factors such as precipitation, human engineering activities induce and aggravate slope disaster development. Viewed the development of collapse disasters in the study area has timeliness and spatiality.Secondly, on the basis of analyzing the collapse characteristics in the study area, using the way of combining theoretical analysis and numerical simulation, study the failure modes and process of the four kinds of typical collapse disasters in the study area. The results by studying the failure modes of collapse prove that toppling collapses emerge vertical fractures influenced by unloading effect, but there has a holding power at the foot of slope; Sliding collapses’ crack and bedding plane are connected and then be destroyed with the affect of friction force in the slope surface and gravity, usually the angle of slope is slightly greater than the slip plane Angle; Pull-splitting collapses formed extension fractures by the force of tension,but there have no holding power below slopes; Sluggered collapses emerge vertical fractures influenced by the gravity and vertically frictional force. Through research the failure process of collapse, this paper has got several conclusions below: the major failure process of toppling collapses is topple; the major failure process of sliding collapses are slippage-fall; the major failure process of pull-splitting collapses is pull splitting-fall-topple; the major failure process of sluggered collapses is slugger-slippage.Finally, in view of four kinds of failure modes collapse disasters, put forward preventive and management measures, to guide the collapse disasters’ prevention and government.