摘要
新建隧道近距离下穿既有盾构隧道,势必会引起既有隧道不均匀变形。以北京地铁12号线西三区间盾构穿越机场专线为工程背景,提出了适合既有运营隧道纵向刚度折减的修正等效连续模型。模型以轨顶面为中性轴位置,可以较好考虑运营隧道对道床、钢轨等结构的影响。数值分析及与已有经验模型对比结果表明,修正等效连续模型预测值与监测值最吻合,验证了模型在本工程中的适应性。从隧道净距及地层性质两方面进行了参数分析,研究结论可为类似盾构下穿既有线路工程提供参考。
When a new tunnel closely passes through an existing shield tunnel,it inevitably causes the deformation and settlement of the existing tunnel and changes the stress state and distribution of the tunnel structure.Based on the project of the shield tunneling undercrossing airport special line of Xiba River-Sanyuan Bridge section of Beijing Line 12,a modified structure model for the existing tunnel was developed.The model takes the top surface of the rail as the position of the neutral axis,which can better consider the impact of the operating tunnel on the track bed,steel rail and other structures.Numerical methods were used to study the influence law of tunnel settlement caused by underpass construction under different longitudinal stiffness of existing tunnels.By comparing with the monitoring data,it is found that the predicted value of the revised model is the most consistent with the monitoring value,which verifies the applicability of the model in this project.Parametric analysis was carried out from the two aspects of tunnel clearance and soil parameters.The research results can provide references for the similar projects.
作者
付春青
张功
张雯超
吴奔
FU Chun-qing;ZHANG Gong;ZHANG Wen-chao;WU Ben(Beijing UniConstruction Group Co.,Ltd.,Beijing 100027,China;School of Rail Transportation,Soochow University,Suzhou 215000,China;School of Architectural Engineering,Nantong Vocational University,Nantong 226007,China)
出处
《科学技术与工程》
北大核心
2021年第17期7319-7326,共8页
Science Technology and Engineering
基金
国家自然科学基金(51978430)
北京住总集团科研项目(QTZC-2019-019)。
关键词
盾构下穿
既有盾构隧道
结构模型
数值模拟
undercrossed tunneling
existing tunnel
structure model
numerical simulation
