降雨作用下滑坡灾害监测预警研究——以遂宁市船山区为例

Study on Monitoring and Early Warning of Landslide Hazard under Rainfall——Taking Sunning Chuanshan as an Example

通过对四川省遂宁市船山区2001—2020年的地质灾害排查和降水量资料分析,区内滑坡灾害90%以上发生在汛期,降雨作为滑坡主要诱发因子,对滑坡之类的斜坡灾害的形成起决定性作用。船山区位于川中丘陵带,境内滑坡地质灾害频发,结合历年滑坡动态变化数据的分析,考虑最大单日降雨量、月累计降雨量与滑坡发生频度的关系,以历史降雨数据和当日降水量数据为依据,建立滑坡降雨预警模型,得出滑坡不同发生概率对应的滑坡失稳破坏前3 d期降水量和当日降水量,结合不同设计频率最大暴雨量计算分析和滑坡不同变形阶段的破坏特征,提出船山区滑坡监测预警模型、预警方案和预警阈值,对增强当地滑坡灾害防御能力和主动避灾防灾具有一定实际依据。

Based on the geological disaster investigation and rainfall data of Chuanshan district from 2001 to 2020,it is found that over 90%of landslide disasters occurred in flood season.As a main factor inducing landslide,rainfall plays a significant role in causing slope geological hazard.Chuanshan district is located in the hilly area of central Sichuan,landslide disasters occur frequently in the area,combined with the analysis of landslide dynamic change data over the years,considering the relationship between maximum daily rainfall,monthly cumulative rainfall and landslide frequency,based on the historical rainfall data and the precipitation data of the current day,early-warning model of landslide rainfall is established,and the three days of precipitation before landslide instability and failure and the precipitation of the current day corresponding to different landslide occurrence probabilities are obtained.Combined with the calculation and analysis of the maximum rainfall at different design frequencies and the damage characteristics of different deformation stages of the landslide,the monitoring and early warning model,early warning scheme and early warning threshold of landslide are proposed within Chuanshan county,which has certain practical foundation for enhancing the local landslide disaster prevention ability and leading disaster avoidance and prevention.