摘要
为预测路堤堆载作用下的土体侧移,为土位移法计算既有高铁桥梁桩基内力及侧移提供条件,本文采用Midas GTS建立二维有限元模型,计算路堤填筑产生的土体侧移,分析土体参数、路堤参数及堆载空间位置等因素对土侧移的影响。对各因素进行敏感性分析,采用响应面法,以5次多项式构建土体侧移与各因素之间的显式关系式。结果表明:路堤填筑后,土层总位移呈“灯泡”形,侧移沿深度方向呈现“弓”形;土体最大侧移随着土体泊松比、路堤堆载等级、路堤填筑宽度增加而增大,随距路堤中心距、土体弹性模量增大而减小;土体侧移对土体泊松比、路堤堆载等级、土体弹性模量、路堤填筑宽度、距路堤中心距离较敏感,对下层岩体的泊松比等因素不敏感;拟合得到的响应面函数可准确预测不同堆载等级下深厚软土土体侧移。研究结果便于快速估算堆载下土体侧向位移。
In order to predict the lateral movement of soil under the stacking of embankments,this paper provides conditions for calculating the internal force and lateral displacement of pile foundations of existing high-speed railway bridges by soil displacement method.In this paper,Midas GTS is used to establish a two-dimensional finite element model,calculate the lateral movement of soil mass caused by embankment filling,and analyze the influence of soil parameters,embankment parameters and stacking space position on soil movement.The sensitivity analysis of each factor is carried out,and the response surface method is used to construct the explicit relationship between the soil lateral shift and each factor in five polynomials.The results show that after the embankment is filled,the total displacement of the soil layer is"bulb-shaped",and the lateral shift is"bow-shaped"along the depth direction.The lateral shift of soil increases with the increase of soil Poisson's ratio,embankment stacking grade and embankment filling width,and decreases with the increase of distance from embankment center distance and soil elastic modulus.Soil lateral displacement is sensitive to Poisson's ratio,embankment stacking grade,soil elastic modulus,embankment filling width,distance from embankment center,etc.,but is not sensitive to Poisson's ratio of underlying rock mass.The fitted response surface function can accurately predict the lateral movement of deep soft soil under different stacking grades.The results facilitate rapid estimation of lateral displacement of soil under pile-loading.
作者
宋旭明
郑梦洋
唐冕
王绍雄
Song Xuming;Zheng Mengyang;Tang Mian;Wang Shaoxiong(School of Civil Engineering,Central South University,Changsha 410075,P.R.China;Yunnan Provincial Transportation Planning and Design Institute,Kunming 650011,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2024年第S01期172-179,共8页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金(52078486)。
关键词
堆载
土体侧移
敏感性分析
响应面
embankment filling
soil lateral movement
sensitivity analysis
response surface
