摘要
研究地基不均匀沉降对加筋土路基力学行为的影响,对于合理认识路基正常服役性能具有重要意义。依托孟加拉国某软土地区铁路对拉反包式加筋土路基工程,进行了缩尺比为1∶2的室内大比例静力物理模型试验,以地基不均匀沉降为基本条件,包括不涉水工况、路堤顶面堆载且涉水工况、不堆载而涉水工况等3种试验工况,测得了相应的加筋土路基的位移与应力变化特征。结果表明:面板侧向位移随地基沉降而增大,地基不均匀沉降可导致面板最大侧向位移增幅为10%,也使路堤顶面及路堤内部沉降呈非线性增大;地基沉降可使路堤底部竖向压应力最大增幅达30%,使反包端后侧土压力沿深度呈重心偏下的抛物线分布,且对路堤中上部反包端土压力影响相对显著;地基沉降增大了土工格栅轴向拉力,最下层拉筋轴力的平均增幅为30%~50%,由下而上对拉筋轴力影响逐渐呈非线性降低。
It is important to study the influence of uneven foundation settlement on the mechanical behavior of reinforced embankment to reasonably understand its serviceability.Based on an end-wrapped geogrid-reinforced railway embankment on soft ground in Bangladesh,a large-scale laboratory static model test with a scale ratio of 1∶2 was carried out.Under the basic condition of the uneven settlement,three test cases were conducted including no water condition,embankment top loading with water action,and water action without the loading.The displacement and stress characteristics of the reinforced embankment were measured.The results show that the lateral displacement of the panel increases with the foundation settlement.The uneven settlement of the foundation causes the maximum lateral displacement of the panel to increase by 10%and the settlement of the top and interior of the embankment to increase nonlinearly.The uneven settlement can increase vertical compressive stress at the embankment bottom by 30%and make the earth pressure at the back of the wrapped end exhibit a parabolic distribution along the depth.The influence on the lateral earth pressure at the middle and upper embankment is relatively significant.The settlement increases the axial tension of the geogrids,with the average increase of the axial force at the lowest reinforcement is 30%to 50%.The influence on the axial force of the reinforcements gradually decreases from the bottom to the top.
作者
肖世国
李绍红
闫清卫
戴天毅
XIAO Shiguo;LI Shaohong;YAN Qingwei;DAI Tianyi(Key Laboratory of High-speed Railway Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;Department of Geological Engineering,Southwest Jiaotong University,Chengdu 610031,China)
出处
《吉林建筑大学学报》
2025年第1期60-67,共8页
Journal of Jilin Jianzhu University
基金
四川省交通运输科技项目(2020-A-01)
中铁二院工程集团有限责任公司科研课题(KYY2018110(18-19))。
关键词
加筋土路基
地基不均匀沉降
模型试验
位移
应力
reinforced embankment
uneven foundation settlement
model test
displacement
stress
