深厚软土地区地下综合管廊边缘路基差异沉降研究

Study on Differential Settlement of Subgrade at the Edge of Underground Utility Pipe Rack in Deep-soft-soil Area

以某深厚软土地区填土路基段的地下综合管廊为背景,运用mIdas GTS有限元软件,采用修正剑桥模型作为本构模型,考虑渗流-应力耦合效应,分别模拟了综合管廊标准段和附属构筑物处路基的差异沉降情况。结果表明:在预压完成后,道路路基仍有一定的工后沉降,而在综合管廊处沉降要小于其他位置,从而造成差异沉降;在标准段结构差异沉降较小且在道路上方未发生沉降突变,而在附属构筑物边缘会产生较大的差异沉降突变;针对不同的差异沉降情况提出了处理方案。

Taking an underground utility pipe rack under filling subgrade in a deep soft soil area as an example,based on midas GTS finite element software,with adoption of modified Cambridge model as the soft soil's constitutive model and considering seepage flow-stress coupling effect,the differential settlement of subgrades at the standard section of utility pipe rack and ancillary structure have been simulated.The results show that there is certain amount of settlement after preloading and the settlement at the utility pipe rack is smaller than that at other places which results in differential settlement.The differential settlement of the standard section of the utility pipe rack is small and there is no sudden change of settlement above the road.However,there is a large sudden change of differential settlement at the edge of the ancillary structures of the underground utility pipe rack.Finally,a treatment plan is proposed for the difference settlement near the standard section and the auxiliary structure.