摘要
研究目的:岩溶的存在会使连拱隧道周围岩土体结构发生变化,以致岩土体强度降低,在列车荷载反复作用下可能导致基底累积变形超限,影响运营安全。针对无碴轨道线路要求,开展隧道溶洞区段处理后基底变形沉降规律研究,避免在长期运营过程中产生较大沉降,影响线路平顺性和无碴轨道板结构,具有重要的现实意义。研究结论:列车单次交汇条件下,隧道支护结构各部位沉降值均小于2 mm,监测点的拉、压应力峰值均小于结构的抗拉、抗压强度设计值,支护结构的位移和变形满足使用要求;列车长期荷载作用下,典型断面基底累积塑性变形小于20 mm,满足相关要求,不会对列车的长期运营造成破坏性影响。
Research purposes： The existence of karst can change the soil structure around the multi-arch tunnel,thereby reducing geotechnical strength of the rock and soil.And under the effect of repeated train-induced load,the deformation of foundation base may exceed the limit value to impact the operation safety of train.Therefore,according to the requirement of ballastless track,it is of practical significance to doing study on the post-construction deformation and subsidence of the tunnel in karst region for avoiding large settlement and impacting the track regularity and the structure of ballastless slab track during long-term operation.Research conclusions：（1） Under the condition of trains meeting at one time,the subsidence of any parts of supporting structure is less than 2 mm and both the maximun tensile and compressive stress are less than the design values.The displacement and deformation of supporting struture can satisfy the design requirement.（2） Under the effect of long-term load of train,the accumulated deformation of typical cross-section of the foundation base is less than 20 mm,which meets the related requirements and has not devastative effects on the long-term service of the track.
出处
《铁道工程学报》
EI
北大核心
2010年第10期82-87,98,共7页
Journal of Railway Engineering Society
基金
铁道部重点计划项目(2003G036-6)
关键词
列车荷载
岩溶段
连拱隧道
基底累积变形
train-induced load
karst region
multi-arch tunnel
accumulated deformation of base
