公路隧道装配式仰拱接头变形破坏规律  

Deformation and Failure Law of Prefabricated Inverted Arch Joints in Highway Tunnels

作　　者：王迎超[1,2] 徐杭 雷雅婷 周鑫 郝英 WANG Ying-chao;XU Hang;LEI Ya-ting;ZHOU Xin;HAO Ying(State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China;School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China)

机构地区：[1]中国矿业大学深地工程智能建造与健康运维全国重点实验室,江苏徐州221116 [2]中国矿业大学力学与土木工程学院,江苏徐州221116

出　　处：《中国公路学报》2024年第7期58-69,共12页China Journal of Highway and Transport

基　　金：国家重点研发计划项目(2022YFC3003304);国家自然科学基金项目(42272313);甘肃省重点研发计划项目(21YF1GA381);甘肃省交通运输厅科技项目(2021-09);中铁十六局集团有限公司科技计划项目(K2023-6B)。

摘　　要：接头部位是公路隧道装配式仰拱受力最薄弱的部位,研究接头的力学性能意义重大。首先,预制仰拱采用弯螺栓连接,通过室内试验研究不同轴力分级加载过程中接缝张开量、竖向位移、接头附近表面混凝土应变等变化规律。然后,建立装配式仰拱接头的三维精细化有限元模型,模拟接头连接形式及接触状态,研究不同轴力-弯矩组合荷载作用下装配式仰拱接头变形、竖向位移以及混凝土应力发展规律。研究结果表明:室内试验和数值模拟获得的弯螺栓抗弯性能具有很好的一致性,且接头破坏过程特征也基本一致,即从接缝靠近施力侧压紧,到对侧张开,再到接头靠近施力侧表面混凝土先产生裂缝,紧接着侧面裂缝斜向上方发展逐渐贯通至顶面,混凝土压坏,最终接头破坏;接缝最大张开量和接头转角随着弯矩的增大,先线性增大后曲线形增大;轴力相同时,接头抗弯刚度随弯矩增加而减小;弯矩一定时,接头抗弯刚度随轴力增加而增加。研究成果可为公路隧道装配式仰拱接头设计及力学性能分析提供参考。The joint is the weakest part of the fabricated inverted arch and the study of its mechanical properties is critical.First,the precast invert was connected using bent bolts.The variation of joint opening,vertical displacement,and surface concrete strain near the joint were studied using laboratory tests.Then,a three-dimensional refined finite element model of the assembled invert joint was established to simulate the joint connection form and contact state,and the deformation,vertical displacement,and concrete stress development law of the assembled invert joint under different combined axial force-bending moment loads were studied.The results show consistency between the bending properties of bent bolts revealed by the laboratory test and numerical simulation,and the fracture process characteristics of joints are basically the same.In other words,from the joint close to the force side compaction,to the opening on the opposite side,and then to the joint near the force side surface of the concrete cracks initially,then the gradual upward development of oblique cracking on the side to the top surface,the concrete is crushed and the final joint damaged.Following the increased bending moment,the maximum joint opening and the joint angle initially increase linearly followed by the curve.With the same axial force,the flexural stiffness of the joint decreases with increase in bending moment.When the bending moment is constant,the flexural stiffness of the joint increases with increasing axial force.The research results can provide reference for the design and mechanical property analysis of prefabricated invert joints in highway tunnels.

关 键 词：隧道工程 装配式仰拱 模型试验 破坏特征 接头转角 

分 类 号：U452[建筑科学—桥梁与隧道工程]