基于非线型滑动面假设的盾构隧道松动土压力计算模型研究  

Research on Calculation Model for Loosening Earth Pressure of Shield Tunnel Based on Assumption of Non-liner Sliding Surface

作　　者：王将 袁大军[1,2] 金大龙 郑爱元[3] 孙庆文 WANG Jiang;YUAN Dajun;JIN Dalong;ZHENG Aiyuan;SUN Qingwen(Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;Shenzhen Metro Group Co.,Ltd.,Shenzhen 518026,China;Jinan Rail Transit Group Co.,Ltd.,Jinan 250014,China)

机构地区：[1]北京交通大学城市地下工程教育部重点实验室,北京100044 [2]北京交通大学土木建筑工程学院,北京100044 [3]深圳市地铁集团有限公司,广东深圳518026 [4]济南轨道交通集团有限公司,山东济南250014

出　　处：《铁道学报》2021年第6期165-172,共8页Journal of the China Railway Society

基　　金：国家重点基础研究发展计划(2015CB057800);国家自然科学基金(51678037,51378054,U1834208);山东省住房城乡建设科技计划(2019-R1-7)。

摘　　要：对于盾构隧道而言,由于上覆土体位移控制较严,松动区边界难以达到传统的竖直线型滑动面状态,而现有的松动土压力计算理论对滑动面形状的假设并不完全适用于这种情况。对此,引入滑移线场理论,考虑非关联流动法则,推导得出盾构隧道松动区边界面的解析表达式,并考虑主应力轴旋转效应,提出了适用于盾构隧道的松动土压力计算模型。将本文模型的计算结果与现场实测结果进行对比,验证了计算模型的合理性;同时与其他经典模型进行比较,并分析了关键参数对计算结果的影响。研究结果表明:松动区的宽度随着剪胀系数的减少而增大;地层的内摩擦角越大,竖向应力分布形式的非线性越为明显。For the shield tunnels,the boundary of the loose zone is difficult to reach the state of the traditional vertical-linear sliding surface because of the strict displacement control of the soil over the tunnel.In the existing theory of loosening earth pressure,the assumptions of sliding surface are not accurate for the shape of the boundary of the loose zone.In this paper,the analytical expression for spiral sliding surface of shield tunnels was derived based on the theory of slip line field and the non-associated flow rule.An analytical solution of loose earth pressure applicable to shield tunnels was proposed based on principal stress axes rotation.The accuracy of this analytical solution was validated by comparing the field measured data and the predicted earth pressures calculated from other classical theories,followed by the analysis of the influence of key parameters on the calculation results.According to the parametric study,the width of loose zone increases with the decrease of dilatancy coefficient.The greater the angle of internal friction of the formation,the more obvious the nonlinearity of the vertical stress distribution.

关 键 词：盾构隧道 松动土压力 非线型滑动面 非关联流动法则 

分 类 号：TU432[建筑科学—岩土工程]