Remote sensing interpretation and risk prediction analysis of Benduo high deformation body in Tibet

This article takes the Benduo high deformed body in the upper reaches of Yigong Zangbo as an example, combined with the methods of field ground survey, UAV integrated photographic survey, optical remote sensing dynamic investigation and numerical simulation prediction, the development characteristics and possibility of the Benduo high deformed body are analyzed. Predict and analyze the risk of forming a disaster chain. The results of the study are as follows: (1) The Benduo high-position deformable body is located in the fault, the rock mass is broken, the rock mass structural surface is developed, and the strength is low. At present, there are 12 small collapses and 64 cracks in the strong deformation of Benduo's high deformation body. (2) According to the interpretation results of InSAR, it is found that the Benduo high-position deformable body has two deformation areas. Among them, the BX1 deformation area is larger and the maximum deformation rate reaches 85 mm/a. Once it loses stability and slides, it has a higher risk of blocking the river. (3) Prediction and analysis of the risk of the deformed body after the instability shows that the Benduo high-level deformed body will block the Yigong Zangbu after the instability, the average thickness of the accumulation body is 90 m, and the backwater length of the dammed lake is 25 km. The backwater area formed by the blockage of the dam poses a higher threat to the downstream villages and towns after the failure of the upstream Zhongyu Village. (4) According to the risk characteristics of the dam body, the treatment plan for the excavation of the spillway tunnel is discussed.