降雨条件下四川绵遂高速石麻湾变形体位移响应特征

Displacement response characteristics of Shimawan deformation body on Sichuan Miansui highway under rainfalls

降雨是诱发斜坡变形的重要因素，斜坡对降雨的响应特征与坡体结构、物质组成、降雨强度密切相关。结合四川绵遂高速公路石麻湾变形体实时监测资料，分析了2012年8月20日雨季至10月10日旱季期间变形体坡表、沉降、地表水平位移及滑面位移对降雨的响应特征。结果表明：在平面空间上，填筑路基区和桥头位置对降雨的响应较强烈，填筑路基区表现为持续累进沉降，桥头位置表现为持续累进水平变形。在竖向上，滑面产生持续累进变形，对降雨的响应十分明显。石麻湾变形体对47．9 mm 的日降雨响应特征更敏感，且对日降雨量在47．9～50．2 mm 的响应表现为突发、部分可逆的过程。

Rainfall is an important factor to induce slope deformation, and the slope response characteristics to rainfall are closely related to the slope structure,material composition,and rainfall intensity.Combined with the real-time monitoring data of the Shimawan deformation body on Miansui highway of Sichuan,this paper analyzes the response characteristics of the deformation body’s slope surface,settlement,ground surface horizontal displacement and sliding surface displacement to rainfalls during the period of 20 August to 10 October 2012.The obtained results show that in the plane,the filling subgrade area and the bridgehead position response to rainfalls is relatively strong. The filling subgrade area appears as a continuous progressive settlement,and the bridgehead position appears as a continuous progressive horizontal deformation.In the vertical direction,the response of the sliding surface displacement to rainfalls is very obvious, producing continuous progressive deformation.The response characteristic of the Shimawan deformation to the daily rainfall of 47.9 mm is more sensitive,while the response to the daily rainfall from 47.9 mm to 50.2 mm is a sudden,but partially reversible process.