摘要
研究目的:分析地基在不同加载次数下的动力反应和沉降规律。数值分析方法中建立三维有限元模型,采用与不平顺管理标准相应的激振力来模拟列车动荷载,采用摩尔-库仑塑性本构模型描述地基土体的受力特性。研究结论:在列车初次运行期间内,地面沿轴向的差异沉降较大,沉降变化是不稳定的;隧道衬砌底部、顶部沉降的变化趋势一致。随着埋深的减少,地基沉降逐渐增加。多次加载过程中,隧道中部的沉降较大并向两端减少;随着运行次数的增多,隧道中部沉降的增加趋势逐渐减弱但其长期累积作用不可忽视;因此,对于长期列车动载作用下地基的变形问题而言,采用塑性本构模型可以合理反应地基土变形的长期累积性。
Research purposes： The analysis is made for the dynamic response and deformation law of the foundation under the different loading quantities of train.The spatial FEM model is established in the numerical analysis.The exciting force corresponding to the irregularity management standard is adopted to simulate the train load and the M-C plastic constitutive model is used to present the load bearing characteristics of the tunnel foundation. Research conclusions：During the the initial running of the train,the ground differential deformation along axial direction is big and the deformation change is variable.The settlements on the bottom and top of the tunnel lining trends to consistent.With the decrease of the buried depth of the tunnel,the foundation deformation increases.During loading of some times,the deformation on the middle part is big and decreases gradually along the longitudinal direction to the two ends.After long time running of the train,the deformation on the middle part increases,but its long-term effect should not ignored.Application of the plastic constitutive model can reasonably present the accumulation of foundation deformation under the effect of long-term load of the train.
出处
《铁道工程学报》
EI
北大核心
2011年第4期22-26,共5页
Journal of Railway Engineering Society
关键词
地铁
移动荷载
地基沉降
数值计算
subway
moving load
foundation deformation
numerical calculation
