隧道掌子面地震动力响应特性及加固方法  

Characteristics of the Earthquake Dynamic Response and Corresponding Reinforcement of the Tunnel Face

作　　者：李斌[1,2] 

机构地区：[1]中铁十三局集团有限公司,天津300308 [2]西南交通大学交通隧道工程教育部重点实验室,成都610031

出　　处：《现代隧道技术》2014年第2期56-62,共7页Modern Tunnelling Technology

基　　金：教育部创新团队发展计划资助(IRT0955);国家自然科学基金(51108056;51178398);天津市企业博后创新项目择优资助(201216)

摘　　要：文章以雅沪高速公路石棉隧道为工程背景,研究分析了地震动力作用对隧道掌子面稳定性能的影响及加固措施。首先,阐述了隧道震害的主要形式及隧道掌子面的力学平衡机理,并采用FLAC3D有限差分软件,针对不同地层中的隧道掌子面进行了地震动力响应分析;其次,通过对比静力和动力下掌子面的稳定状况,分析地震对不同地层中隧道掌子面稳定性的影响,总结出了掌子面挤出变形和约束压力随地震时程的变换规律,并通过掌子面平均塑性剪切应变、掌子面挤出变形、掌子面约束压力等参数评估了加固效果。分析结果表明,与隧道衬砌相比,隧道掌子面更容易受到地震的破坏;地震动力作用对不同地层条件中隧道掌子面的影响程度是截然不同的,岩质地层中隧道掌子面受到的影响较小,而土质地层中隧道掌子面所受影响则很大;锚杆的加固作用能显著提高隧道掌子面的抗震性能。Based on the Shimian Tunnel on the Ya＇an-Lugu highway, this paper analyzes the effects of the earthquake dynamic response on the tunnel face and corresponding reinforcement measures. First, it describes the main types of earthquake hazards in tunnels and the mechanical equilibrium mechanism at the working face, and performs an earthquake dynamic response analysis using FLAC3D finite difference software aiming at analyzing the effects of earthquake on stability of working faces in different strata through comparing the working face stability condition under static and dynamic action. Then it summarizes the law of extrusion deformation and confinement pressure varying with the time-history of an earthquake. Using the average plastic shear strain, extrusion deformation and confinement pressure at the working face, it evaluates the reinforcement effects on the working face. Finally, it derives the following conclusions： the tunnel working face is more likely to be destroyed by an earthquake than the tunnel lining; there are different degrees of influence of the earthquake dynamic response on the tunnel working face in various strata, that is to say, the impact is less in a rocky stratum and greater in a soil stratum; and anchor reinforcement greatly improves the aseismic performance of the tunnel working face.

关 键 词：隧道工程 掌子面稳定性 地震动力响应 超前加固 锚杆加固 

分 类 号：TU352.1[建筑科学—结构工程]