[Objective]To reveal the deformation evolution of the Xinhua landslide in Luding County,Sichuan Province under the comprehensive effects of reservoir impoundment,reservoir water level fluctuations and seasonal rainfall,and to explore the progressive cumulative effect of the strength degradation of the landslide rock and soil mass under the coupling of multiple factors.[Methods]In this paper,based on a field investigation and multi-source long sequence monitoring data analysis of the Xinhua landslide in the reservoir area of the hydropower pro-ject,combined with the three-stage evolution characteristics of the landslide cumulative deformation-time(S-t)curve and the measured S-t curve of the Xinhua landslide,the evolution stages of the three-step deformation cycles of the Xinhua landslide are identified and divided.At the same time,the improved tangent angle method is used for calculation and analysis,and a quantitative classification standard for Xinhua landslide classification early warning based on the improved displacement tangent angle early warning threshold is constructed.[Results]The results show that the short-term large increase of water level during the initial impoundment period,the rapid decrease of water level during the reservoir operation period and the influence of seasonal heavy rainfall are the main factors to accelerate the deformation of the Xinhua landslide.[Conclusion]According to the analysis and discussion,the improved displacement tangent angle early warning threshold can provide guidance for identifying the current stabili-ty state and potential risks of the Xinhua landslide to a certain extent,but multiple early warning indicators should still be considered,and the signs of macroscopic deformation and failure of landslides should be integrated for judgement.
关键词
库区滑坡/水位波动/变形监测/演化规律/预警判据/四川新华滑坡
Key words
reservoir landslide/water level fluctuation/deformation monitoring/evolution law/early warning cri-terion/Xinhua landslide in Sichuan Province
维普
万方数据