非线性土体损失对隧道施工引起的砂土地层沉降影响

摘要

目的 基于经验方法及试验分析,研究砂土中隧道开挖考虑非线性土体损失变化对地层沉降的影响规律.方法 对比分析隧道开挖引起的地层沉降经验计算方法,确定适用于砂土中隧道开挖引起的地层沉降的计算公式;通过分析及反演,给出砂土中隧道开挖过程中隧道土体损失率和地层土体损失率之间的非线性关系表达式,完善砂土中隧道开挖引起的地层沉降的计算方法.结果 砂土中隧道土体损失率与地层土体损失率之间存在非线性关系,并对地层沉降计算结果有显著影响.结论 通过与多组离心机试验及模型试验对比分析,验证了反演公式的合理性,完善了砂土中隧道开挖引起的地层沉降经验分析方法.%The paper focus on the stratum settlement considering non-liner volume loss induced by tunneling in sand,which is based on empirical method and experimental analysis.By comparing the empirical method used for calculating the stratum settlement,the formula suit for the sand stratum is obtained.Meanwhile,it's different from the clay,the tunnel volume loss ratio and settlement trough volume loss ratio are not equal,hence causing remarkable differences.Non-liner relationship between tunnel volume loss and settlement trough volume loss is obtained through analysis and inversion.The relationship improve the empirical method used for calculating the stratum settlement induced by tunneling in sand.The formula is considered reasonable for the tunneling by comparing with geo-centrifuge tests and model test.