基于集对分析-可变模糊集耦合模型的软土基坑施工对周围环境影响分析

Influence Analysis of Soft Soil Foundation Pit Construction on Surrounding Environment Based on Set Pair Analysis-Variable Fuzzy Set Coupling Model

随着中国城市地下空间建设的不断发展,基坑工程不可避免地受周边道路、建筑、市政管网等限制,这就要求施工过程中不仅要保证基坑自身安全,更要尽可能减少对周围环境的损伤,因此评估环境风险性研究成为新的热点。以德州市某社区棚改项目为研究对象,在利用数值模拟得到软土基坑施工所造成的地表沉降特征规律的基础上,结合应变叠加法、路面损坏状况指数法以及管线安全性状失效系数法对地表沉降所诱发的环境损伤进行评定,构建并细化了环境影响评价指标体系和风险性等级划分标准。同时,引入集对分析联系度函数和可变模糊理论,采用联系度和相对隶属度函数来实现环境风险性评价指标与风险等级之间的反映联系和评价指标自身间的有机融合,建立集对分析-可变模糊耦合模型,从而实现对软土基坑环境风险性的预测评价,为今后工程施工管理提供重要经验和依据。

With the continuous development of China's urban underground space construction,foundation pit engineering can not avoid the restrictions of surrounding roads,buildings,municipal pipe network and so on,which requires the construction process not only to ensure the safety of foundation pit itself,but also to reduce the damage to the surrounding environment as far as possible.Therefore,the research on environmental risk assessment should become a new hot spot.A community shed renovation project in Dezhou City was taken as the research object,and the surface settlement characteristics caused by soft soil foundation pit construction were obtained by numerical simulation.On this basis,the environmental damage caused by surface settlement was evaluated by combining the strain superposition method,pavement damage index method and pipeline safety property failure coefficient method,the index system of environmental impact assessment and the standard of risk classification were constructed and refined.At the same time,the set pair analysis connection degree function and variable fuzzy theory were introduced,and the connection degree and relative membership function were used to realize the reflection connection between the environmental risk assessment index and the risk level,and the organic integration of the assessment index itself.The set pair analysis variable fuzzy coupling model was established,so as to realize the prediction and evaluation of the environmental risk of soft soil foundation pit.It provides important experience and basis for future project construction management.