Study On The Load-displacement Coupled Prediction Parameters And Catastrophic Dynamic Prediction Criterion Of The Landslides Induced By Extreme Rainfall

Slope instability under the influence of extreme rainfall have existed in the worldwide, and such geological environment problems accounted for a large proportion oflandslide disaster in China. Extreme rainfall events are different from ordinary rainfallevents, once occurs, it will not only affect the current state of landslide stability, but alsoendanger the life safety of personnel in this region. Debris landslide occupies a largerproportion in landslide disaster. Studying on dynamic evolution and catastrophicdynamic prediction criterion of such slope under the influence of extreme rainfall has avery important theoretical and practical significance.Selecting the landslide of extreme rainfall type as the research background, andsupported by the projects of National Natural Science Foundation of China “LandslideDisastrous Dynamics Mechanism of the Compound Water Environments in MajorWater Conservancy Engineering Region and its Prediction Model (Code No.:41372297)”, the Special Research Foundation of Doctoral Program of the Ministry ofEducation “Debris landslides seepage unload-load dynamic prediction method andinstability criterion research (Code No:20113721110002)” etc. Selecting Fanlingqianslope in the Laoshan region as the example, the thesis has carried out a study on thegeneralized model of the debris landslide by means of the numerical simulationsoftware-Geo-studio, and studied the parameter evolution of the displacement responseratio of dynamic increment and the verification of practical application&analysis at thesame time, some results are summarized as follows:1) On the basis of geological survey of Fanlingqian slope in the Laoshan regionand Xintan landslide Three Gorges region, and the data analysis of landslide geologicalcharacteristic, definition domain of extreme rainfall and variable rule of mechanicalengineering geological parameters are determined.2) On the basis of evolution of the landslide induced by extreme rainfall. Dynamicevolution characteristics of instability process are analyzed and explained.3) By means of the displacement response ratio of dynamic increment theory tothe prediction of debris landslide, the feasibility of using extreme rainfall changes asdynamic increment parameters and displacement changes as dynamic incrementresponse is discussed, it is Proved that the slope instability mechanism can be completely described by the displacement response ratio parameters of dynamicincrement.4) On the basis of the basic theory of damage mechanics and elastic-plasticmechanics, the displacement response ratio model of dynamic increment is establishedby geotechnical software-Geo-studio. If the displacement response ratio of dynamicincrement is1or fluctuated near1, slope is in undamaged elastic deformation stage; ifresponse ratio is above1and deviates Increasing, slope is in unstable elastic damagedeformation stage; if response ratio appears mutation, and even tends to infinity, slope isin the critical integral instability stage, and indicates that the slope is unstable.5) Setting Xintan debris landslide as an example on application analysis stage,actual development trend of slope is coincides with results analysis. Application of thedisplacement response ratio of dynamic increment can identify and predict stability ofthe state slope under dynamic rainfall condition, and the operation of dynamicparameters is showed...