机构地区:[1]中国铁路经济规划研究院有限公司地质路基咨询部,北京100038 [2]中南大学土木工程学院,湖南长沙410075 [3]中南大学高速铁路建造技术国家工程研究中心,湖南长沙410075 [4]中铁第四勘察设计院集团有限公司地质路基设计研究院,湖北武汉430063
出 处:《铁道科学与工程学报》2023年第9期3203-3216,共14页Journal of Railway Science and Engineering
基 金:国家重点研发计划(2022YFB2603301);国家自然科学基金资助项目(52078498);湖南省自然科学基金资助项目(2022JJ30745);湖南省科技托举人才项目(2020TJ-Q19);中国中铁股份有限公司科技研究开发计划项目(2021-专项-04-2);中南大学前沿交叉研究项目(2023QYJC006)。
摘 要:为了解决低墩桥梁造价高,传统路基填料耗费多、占地面积大等难题,提出新型“箱式路基”结构。然而在高速铁路运营过程中地基不可避免会发生不均匀沉降,影响箱式路基服役性能和列车的安全运行。为确定新型箱式路基结构的沉降限值,从轨道结构受力变形和列车走行性2方面研究了地基沉降对箱式路基静、动力学特性的影响。考虑有砟和无砟2种轨道形式,根据箱式路基结构特点确定了错台、折角、对折和横向错位4种沉降类型;通过建立轨道−箱式路基非线性有限元模型,分析了不同沉降类型和沉降幅值下的扣件竖向力和10 m弦长矢度值;建立列车−轨道−箱式路基耦合动力学模型,采用联合仿真方法分析了不同沉降类型、不同沉降幅值和不同行车速度下的列车动力响应;综合静力、动力计算结果并结合规范得出了箱式路基沉降限值。研究结果表明,对于有砟轨道−箱式路基结构,除350 km/h错台沉降工况下的沉降限值由动力指标中的轮重减载率控制外,其他工况下的沉降限值均由静力指标中的10 m弦长矢度值控制;对于无砟轨道−箱式路基结构,其沉降限值不受动力指标控制,错台、横向错位沉降限值由扣件竖向力控制,折角、对折沉降限值由10 m弦长矢度值控制。有砟轨道−箱式路基在错台、折角、对折和横向错位4种沉降下的限值分别为4.02,17.63,9.17和5.53 mm,无砟轨道−箱式路基在4种沉降下的限值分别为2.48,17.43,8.79和2.55 mm。To reduce the high cost of low-pier bridges,the huge demand for fillers,and the large occupancy areaof traditional subgrade,a new type of concrete box subgrade structure has been developed in China.However,in high-speed railway operating conditions,the uneven settlement of the ground is inevitable,which affects the service performance of the concrete box subgrade and the running safety of the train.To obtain the settlement limits of the new type of concrete box subgrade structure,the influences of ground settlement on track deformation,force and vehicle dynamic responses were investigated in this paper.Taking both ballasted track and ballastless track into consideration,four types of settlement analysis were considered according to the structural characteristics,including box faulting,trapezoid settlement,V-shape settlement and box rolling.Based on the nonlinear finite element model of track-concrete box subgrade,the vertical fastener force and 10 m chord versine of vertical irregularity with different settlement types and values were investigated.Based on the train-trackconcrete box subgrade dynamic model,the train dynamic responses with different settlement types,different settlement values and different running speeds were studied by adopting a real-time co-simulation method.On this basis,the settlement thresholds of concrete box subgrade were determined according to China’s codes.The results show that for the ballasted track-concrete box subgrade structure,except that the settlement threshold with box faulting at the speed of 350 km/h is determined by wheel unloading rate,the settlement thresholds of all the other settlement conditions are controlled by 10 m chord versine of vertical irregularity.For the ballastless trackconcrete box subgrade structure,the settlement thresholds are not controlled by the dynamic indicators.The settlement thresholds with box faulting and box rolling are controlled by the vertical force of fasteners,and the settlement thresholds with trapezoid settlement and V-shape settlement
关 键 词:箱式路基 有砟轨道 无砟轨道 轨道变形 行车安全性 沉降限值
分 类 号:U238[交通运输工程—道路与铁道工程]
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