土体小应变硬化模型在铁路既有线沉降评估中的应用  

Application of Soil Small Strain Hardening Model in Settlement Evaluation of Existing Railway Lines

作　　者：门士林 MEN Shilin(China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]中国铁路设计集团有限公司,天津300308

出　　处：《铁道勘察》2025年第1期40-45,51,共7页Railway Investigation and Surveying

基　　金：中国铁路设计集团有限公司科技研究开发计划重点课题(N2021B240606)。

摘　　要：由于土体小应变模型可以考虑小应变条件下土体模量的非线性、应力相关等特性,已被广泛应用于建筑基坑变形的分析中,但在铁路工程中的应用尚不充分。基于室内压缩试验结果和上海市基坑规范建议方法,对修正剑桥(MCC)模型、土体硬化(HS)模型和土体小应变硬化(HSS)模型参数进行率定。结果表明,河北地区黏土中与应力水平相关的指数取值范围在0.5~0.7。利用有限元方法,对比分析3种模型在既有铁路帮宽变形中的结果差异,在网格尺寸一定的条件下,MCC模型计算得到的沉降值最大,HS模型次之,HSS模型最小。HS模型和HSS模型的最大沉降计算结果分别为MCC模型的66%和56%。针对天津地铁13号线U形槽上跨盾构隧道,利用HSS模型分析不同施工阶段下盾构隧道变形的发展规律,计算结果与实测值的差异在10%以内,表明HSS模型在既有铁路沉降分析中具有较好的适用性。The Hardening Soil Model with Small strain has been applied in the analysis of deformation in municipal engineering foundation pits due to its consideration of the nonlinear and stress related characteristics of soil modulus under small strain conditions.,but its application in railway engineering is not yet sufficient.Based on the results of one-dimension compression tests and the recommended methods of Shanghai excavation standards,the parameters of the modified Cambridge(MCC)model,soil hardening(HS)model,and soil small strain(HSS)model were calibrated.The results indicate that the HSS model parameters related to stress levels in the clay of Hebei region range from 0.5 to 0.7.By using the finite element method,the differences in the results of three models in the deformation of existing railway embankments were compared and analyzed.Under the condition of a fixed grid size,the settlement value calculated by the MCC model was the largest,followed by the HS model,and the HSS model was the smallest.The maximum settlement calculation results of the HS model and HSS model are 66%and 56%of those of the MCC model,respectively.The HSS model was used to analyze the development law of shield tunnel deformation under different construction stages for the U-shaped groove overpass shield tunnel of Tianjin Metro Line 13.The difference between the measured arch deformation of the foundation pit and the calculated results was within 10%,indicating the applicability of the HSS model in the settlement analysis of existing railways.

关 键 词：高速铁路 地铁 路基 帮宽 小应变模型 开挖变形 

分 类 号：U238[交通运输工程—道路与铁道工程] U231U213.1