铁路隧道穿越岩溶区施工引起地表变形预测  

Prediction of Surface Deformation During Construction of Railway Tunnels Crossing Karst Areas

作　　者：刘荣 Liu Rong(The Fifth Engineering Co.,Ltd.of China Railway 18th Bureau Group,Tianjin 300450,China)

机构地区：[1]中铁十八局集团第五工程有限公司,天津300450

出　　处：《市政技术》2023年第6期129-136,共8页Journal of Municipal Technology

摘　　要：为获得铁路隧道穿越岩溶区施工所需的施工参数,以渝昆高铁云贵段站前工程YKYGZQ-5标乐业隧道为例,在半无限空间内分别考虑不同施工荷载因素的影响,利用Mindlin解析法建立铁路隧道穿越岩溶区施工引起地层竖向位移预测模型,给出各种因素影响下的地表沉降量预测曲线,并通过与实际工程监测结果的对比分析,验证预测模型的工程适用性。结果表明:正面开挖力、开挖引起的岩溶区围岩摩擦力和开挖间隙荷载均为铁路隧道穿越岩溶区施工引起地层竖向位移的主要影响因素,且同一断面上地表沉降量均表现为“中间大、两边小”的正态分布规律。该研究中所建立的预测模型计算精度较高,最大误差仅约8%,远小于工程经验规定的20%的限值,可为类似工程地质条件下隧道施工中的地表变形控制提供理论指导。In order to obtain the construction parameters required by railway tunnel crossing karst areas,taking the YKYGZQ-5 Leye Tunnel of the Yungui section of the Chongqing-Kunming high-speed railway as an example,the influence of different construction load factors were considered in a semi infinite space.The Mindlin analytical method was used to establish a prediction model for vertical displacement of the strata caused by railway tunnel crossing karst areas during construction.The prediction curves of surface settlement under the influence of various factors was obtained.The engineering applicability of the prediction model was verified by comparative analysis of actual engineering monitoring results.The results show that the front excavation force,the friction force of surrounding rock in karst area caused by excavation and the excavation gap load are the main influencing factors for the vertical displacement of stratum caused by the construction of railway tunnels crossing karst area.The surface settlement on the same section shows the normal distribution law of"large in the middle,small on both sides".The prediction model established in this study has high calculation accuracy with a maximum error of only about 8%,which is far less than the 20%limit specified by engineering experience.It can provide theoretical guidance for surface deformation control under similar engineering geological conditions.

关 键 词：铁路隧道 岩溶区 MINDLIN解 地层竖向位移 预测模型 

分 类 号：U455[建筑科学—桥梁与隧道工程]