高速铁路堆载预压路基基底土厚度与沉降量关系研究

Research on the Relationship Between Thickness of Foundation Soil and Settlement of Preloaded Subgrade under Load of High-speed Railway

为研究堆载预压情况下高速铁路路基基底土厚度与沉降量的关系,在分层总和法的基础上,从土体结构在x、y和z方向上与法向应变有关的本构关系式进行分析,推演得到一种路基基底土厚度与沉降量的非线性公式模型。以实验站房的两段堆载预压路基工程为依托,将基底土分为抗压土和非抗压土。通过搜集堆载预压期间的沉降监测数据,将推演的非线性公式模型输入到SPSS专业统计软件,对路基基底土质厚度与沉降量相关关系进行非线性曲线拟合,最终迭代计算得到拟合公式,其相关系数R^(2)结果分别为0.78和0.89。采用该研究成果,可通过路基基底土厚度计算堆载预压后的最终沉降量,还能够计算邻近无观测断面处的沉降量,弥补采样间隔的数据缺失。

In order to study the relationship between soil thickness and settlement of high-speed railway subgrade under load preloading,based on the layered summation method,the constitutive relation of soil structure with normal strain in x,y and z directions was analyzed,and a non-linear formula model of soil thickness and settlement of subgrade foundation was deduced.Based on the two sections of preloading subgrade by loading in the experimental station house,the soil of the subgrade was divided into compressive soil and non-compressive soil.Through collecting settlement monitoring data during surcharge preloading,the deduced non-linear formula model was input into SPSS professional statistical software,and the non-linear curve fitting was carried out for the correlation between soil thickness and settlement of subgrade foundation.Finally,the fitting formula was obtained by iteration calculation,with the R^(2) correlation coefficient of 0.78 and 0.89 respectively.Using this research result,the final settlement after loading preloading can be calculated by the thickness of subgrade foundation soil,and the settlement near the unobserved section can also be calculated to compensate for the missing data of sampling interval.