摘要
我国接近1/3国土面积属于严寒地区。高速铁路路基采用水泥基材料进行局部防水封闭,存在大量结构缝,部分严寒区段防水失效引发冻害。沥青混凝土防水封闭结构具有全断面封闭防水性能,在高平顺性标准和60年使用寿命条件下,沥青混凝土封闭层在高速铁路结构体系中的工作状态复杂,其长期服役风险评估尚待研究。本文通过原位足尺模型试验和仿真分析,研究周期性温度效应作用下基床-沥青混凝土封闭层-无砟轨道结构体系受力变形的时空分布特征及演变规律。研究结果表明:温度效应是造成底座板结构缝处沥青混凝土层受迫拉伸的主要原因;在沥青混凝土表面底座板结构缝两侧铺设复合土工膜可有效改善沥青混凝土防水封闭结构的受力状态,显著降低其拉伸应变;当复合土工膜铺设范围为结构缝两侧各1. 2 m时,应变约减小60%。
About 1/3 of China land area is in severe cold regions.The cement-based materials are used for local subgrade waterproof and seal of high speed railway.There are a large number of structural seams,thus in some cold regions,waterproof failure of structural seam causes signif icant frost damages.The asphalt concrete waterproof sealing structure has a better whole section waterproof performance.Under the conditions of high smoothness demand and 60 years of service life,the working state of asphalt concrete sealing layer in high speed railway structure system is complex,and the long-term service risk assessment was rarely studied.By in-situ full-scale model test and numerical simulation,the spatio-temporal distribution and evolution laws of stress and deformation of high speed railway subgrade-asphalt concrete sealing structure-ballastless track structure system were analyzed under the cyclical temperature effect.The results show that temperature effect is the major factor which causes the forced stretch of asphalt concrete layer near base slab structure seams.Laying composite geomemanes on the surface of asphalt concrete layer could effectively improve the stress state and obviously decrease the stretching strain of asphalt concrete layer.While the width of composite geomemane is 1.2 m from each side of structure seam,the strain of asphalt concrete layer could decreases about 60%.
作者
李泰灃
蔡德钩
闫宏业
包黎明
张新冈
吕宋
LI Taifeng;CAI Degou;YAN Hongye;BAO Liming;ZHANG Xingang;LYU Song(Railway Engineering Research Institute,China Academy of Railway Sciences Group Co.Ltd.,Beijing 100081,China;China Railway Economic and Planning Research Institute Co.Ltd.,Beijing 100038,China;Engineering Design Appraisal Center,China Railway Corporation,Beijing 100844,China;China Academy of Railway Sciences Group Co.Ltd.,Beijing 100081,China;School of Civil Engineering and Architecture,Beijing Jiaotong University,Beijing 100080,China)
出处
《铁道建筑》
北大核心
2018年第10期63-68,共6页
Railway Engineering
基金
中国铁路总公司科技研究开发计划(2017G008-B)
关键词
高速铁路
温度效应
试验研究
沥青混凝土
板间应变
High speed railway
Temperature effect
Experimental study
Asphalt concrete
Strain between slabs
