| Rapid and long runout landslide is one of the main geological hazard in the world. Thereare the characteristics of sliding distance, sliding velocity, impact damage resistance. It caused agreat damage to the environment for human survival and life. At home and abroad for the rapidand long runout landslide made a lot of achievements in scientific research, but because of theearly recognition and spatial prediction ability for this kind is poor, difficult, bring about massdeath and casualty disasters still occur. So for the early identification of rapid and long runoutlandslide, law of motion and the study of the mechanism is of great practical significance.In this paper, Jiweishan landslide as an example, based on detailed field investigation andrelated survey technique application, compared with the characteristics of the terrain beforesliding and the deposit after sliding, established the motion geological model of rapid and longrunout landslide, analyses the main factors of Jiweishan landslide long distance movement.Sliding in the process of scraping and erosion mechanical model is established, and putsforward the significance of impact scraping and entrainment scraping in movement process, thecalculation formula of the scraping effect of landslide. In this paper, through research, obtainedthe following main conclusions and achievements:1. The establishment of Jiweishan landslide movement of rapid and long runout geo logicalmodel. Through the characteristics comparative study of the before sliding and the after sliding,summed up landslide movement process has undergoneas to high speed start, scrapingdisintegration, impact accumulation and debrisdeposit of continuous motion stage. In thisprocess, but also reflects the disintegration process: the sliding body from the whole bulk to thedispersions to debris body.2. This paper analysisscraping mechanical model of the rapid and long runout landslide inmovement process. The scraping effect is mainly divided into: impact scraping and entrainmentscraping. Collision scraping based on Hertz theory always occursat the collision stagefor thelandslide better integrity; Entrainment scraping based on the equivalent fluid always occurs inthe sliding body disintegrated into debirsbody, the high speed lead toeroding on theloose basallayer.3. Numerical simulation of Jiweishanlandslide based on DAN software. The FVF basal resistance rheological model that obtained the thickness, moving distance and velocitydistribution is consistent with the actual situation.And it is consistent with the geological modelof the movement. The scraping effect increased the landslide movement distance, alsoincreased the average thickness. |
