山区沿河公路地质风险形成机制

Formation Mechanism of Geological Risk of Mountainous Highway along River

根据山区沿河公路灾害的特点,将以岩土介质为主的传统地质灾害类型和水沙介质灾害类型整合,提出了"广义地质灾害体"的概念,并以介质组成为标准进行了广义地质灾害体分类。在孕灾环境评价和致灾因子评价的基础上,提出了广义地质灾害体的孕灾环境与致灾因子异相耦合发育机理。基于公路承灾体健康的理念,认为公路承灾体易损性主要受控于公路结构本身的健康性态,采取技术可行、经济合理的技术措施使结构健康复原是工程性减灾措施的目的。将公路承灾体类型分为结构性承灾体和功能性承灾体两类。提出了公路地质风险的耦合对抗形成机制,即公路地质风险是广义地质灾害体危险性与公路承灾体易损性之间时空耦合对抗的结果。认为地质风险评估是关于多因素非线性灾害风险系统的预测评价问题。根据地质风险形成的耦合机制,提出了采用解耦措施来逆向控制公路地质风险形成演化过程的减灾思路。针对山区沿河公路,给出了从孕灾环境、致灾因子、广义地质灾害体危险性、承灾体易损性评价到地质风险评估的思路与一般函数表达式。

According to the characteristics of mountainous riverside highway disasters, combined traditional geotechnical medium geological disasters and flood and sediment disasters, the authors put forward the ＂generalized geological disasters body＂ concept, and classified the generalized geological disasters body using medium composition for standard. Based on the evaluation of disaster-breeding environment and disaster-causing factor, the catastrophe- coupling development mechanism of the generalized geological disasters body by interaction between disaster-breeding environment and disaster-causing factor is given. Based on the health concept of highway hazard-affected body, it is thought that vulnerability of hazard-bearing body is mainly controlled by the healthy condition of highway structure. The purpose of engineering disaster alleviation measures is making structure health recovery by taking technically feasible and economy reasonable measures. The highway hazard-affected bodies are divided into two types as structural and functional ones. The coupling and confrontation mechanism of highway geological risk is put forward, which indicates that highway geological risk is the result of coupling and confrontation between hazard of generalized geological disasters body and vulnerability of highway hazard-bearing body. It is thought that geological risk assessment is about the prediction and evaluation study on the multi-factors and nonlinear disaster risk system. According to the coupling formation mechanism of geological risk, the idea for reverse control of the formation processes of highway geological risk b~ decoupling measures is proposed. For mountainous riverside highway, the work ideas and general function expressions for disaster-breeding environment, disaster-causing factors, hazard of generalized geological disasters body, vulnerability assessment of hazard-bearing body and geological risk assessment are given.