山区公路高边坡工程开挖施工安全风险评估技术——以湖北山区为例

Safety Risk Evaluation Technology for Excavation Construction of Expressway High Slope in Mountainous Area:A Case Study in Mountainous Areas of Hubei Province

为提高高速公路路堑高边坡工程施工安全管理水平,有效控制施工安全风险,针对湖北地区的地形地质条件和施工作业环境,选择湖北郧十高速、恩黔高速等6条在建高速公路的160处高边坡和深基坑工程的施工安全风险评估技术进行案例研究,并向国内相关专家发放并有效回收89份问卷调查,通过归纳总结和计算分析,得出施工安全风险事故可能性大小和稳定性经验修正系数,构建了山区公路高边坡开挖工程施工安全风险评估指标体系,提出施工前和施工过程中两个阶段的专项评估流程。所得研究成果在某公路边坡开挖工程安全评估应用中,发现该高边坡工程爆破开挖作业存在坍塌事故风险等级为高度风险,相关针对性风险防控措施为施工安全分级管理措施的制定提供了安全技术决策支持。

In order to improve the safety management level of expressway subgrade high slope construction and control the potential safety risks, in view of the topographic and geological conditions and construction working environment in Hubei area, a case study on construction safety risk assessment technology for 160 high slopes and deep foundation pits of six expressways in construction (such as Yunshi Expressway and Enqian Expressway in Hubei Province) was carried on. 89 questionnaires were distributed to relevant local experts and collected effectively. Through summarizing and calculating analysis, the empirical correction coefficients for the possibility and stability of potential construction safety risk accidents were proposed. A construction safety risk assessment index system of expressway high slope excavation project in mountainous area was constructed. A special evaluation process of the two-stage assessment process, namely pre-construction stage and construction stage, was put forward. The research results were applied in the safety assessment of an expressway slope excavation project. It is found that the risk grade of collapse accidents in blasting excavation of this high slope project was high, and the targeted risk prevention and control measures provided technical decision support for the graded management of different risk levels.