暴雨工況下老舊砌石擋墻滑坡變形特征與應急處置措施

摘" 要：近年來，鎮江城區每年汛期都有地質災害險情發生，發生時間集中于暴雨后，其險情以滑坡為主，擋土墻垮塌引起的滑坡險情占比大于等于50%。某小區健身廣場西側滑坡發生于2023年7月11日，為強降雨后第四天，屬于典型的暴雨工況下老舊砌石擋墻垮塌引發的滑坡地質災害。該文通過對該滑坡的變形特征進行研究，總結出該類滑坡險情的主要影響因素為地層巖性、地形地貌、降雨影響和砌石擋墻老舊等。提出當邊坡為砌石擋墻支護而產生滑坡災害時，可將擋墻看作是一個具有一定抗剪強度的巖土體進行分析，所得到的邊坡穩定性結果更符合實際，具有一定的創新性。對該類型滑坡提出針對性的應急處置措施，對類似地質災害險情處置具有一定的借鑒意義。

關鍵詞：滑坡;強降雨;砌石擋墻;變形特征;應急處置

中圖分類號：P694" " " 文獻標志碼：A" " " " " 文章編號：2095-2945（2024）26-0146-06

Abstract： In recent years， there are geological hazards in Zhenjiang urban area every year in flood season. The occurrence time is concentrated after rainstorm， and the main danger is landslide. The proportion of landslide hazards caused by the collapse of retaining wall is greater than or equal to 50%. On July 11， 2023， the fourth day after rain， the landslide on the west side of the fitness square in a community is a geological disaster caused by the collapse of the old masonry retaining wall under the influence of a typical rainstorm. This article summarizes the main influencing factors of this type of landslide risk through the study of its deformation characteristics， including geological lithology， terrain and topography， rainfall influence， and old masonry retaining walls. When the slope is supported by masonry retaining walls and landslide disasters occur， the retaining wall can be considered as a rock and soil mass with a certain shear strength for analysis. The obtained slope stability results are more in line with reality and have a certain degree of innovation. Targeted emergency response measures are proposed for this type of landslide， which has certain reference significance for similar geological hazard situations.

Keywords： landslide; heavy rainfall; stone masonry retaining wall; deformation characteristics; emergency response

鎮江市在城市發展過程中修建了大量重力式砌石擋土墻，年限較久，一旦砌石擋土墻變形受損，將會導致邊坡失穩，引發滑坡地質災害。尤其汛期，長期強降雨不僅使墻后土體失穩，還可能直接導致墻體失效而引發滑坡災害。根據統計，2012—2023年度汛期，鎮江市區共發生88處地質災害險情，其中有48處為擋土墻滑塌引起的地質災害（圖1），占總數的55%。僅2023年汛期，鎮江市區共發生10處地質災害險情，其中就有5處（50.0%）為擋土墻垮塌引發的滑坡災害（圖2），不僅給相關部門帶來防控壓力，還直接威脅到居民的生命財產安全。……