新建工程穿越既有地铁项目脆弱性评价研究

Assessment of Vulnerability for System of New Construction Crossing the Existing Metro

风险承灾体系统的脆弱性评价是风险分析和控制的关键。将新建工程、围岩介质和既有地铁作为一个整体系统,分析系统的风险因素和脆弱性特性,首次在穿越工程领域提出承灾体系统的脆弱性评价方法。选用暴露度、适应度和敏感度三要素作为脆弱性评价的一级评价指标,并结合工程实践和文献成果,选取新建工程特性、既有地铁特性和应急预案等11 项指标作为脆弱性评价的二级评价指标。基于突变理论的基本原理,建立脆弱性评价的数学模型,同时对脆弱性指数的计算结果进行数学调整,使其更符合传统的评价概念,并结合工程实践,划分脆弱性等级,有利于穿越工程的分级管控。通过实际工程案例的应用,验证方法的有效性和实用性。

Vulnerability assessment of risk-bearing body systems is fundamental in risk analysis and control. This paper analyzes the risk factors and vulnerability characteristics of new systems, surrounding rock media, and existing metros as a whole system;and builds a novel vulnerability assessment system in the engineering field. The model uses exposure, fitness, and sensitivity as the first-level evaluation index, and selects new engineering characteristics, existing metro characteristics, and emergency plans as the secondary indicator of vulnerability assessment, based on finished engineering projects and published works. Thus, the vulnerability evaluation model is established based on catastrophe theory. Meanwhile, the calculation results of the vulnerability index are mathematically adjusted to make it consistent with traditional risk assessment. Combined with engineering examples, the vulnerability level is divided into different degrees, which facilitates management at different degrees. The effectiveness and practicality of the method are verified by the application of actual engineering cases.