素填土回填下拱涵垂直土压力影响因素研究  

Study of Factors Affecting Vertical Earth Pressure in Arch Culverts Under Plain Fill Backfill

作　　者：刘文轩 杨伟军 杨建宇 LIU Wenxuan;YANG Weijun;YANG Jianyu(College of Civil Engineering,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《河南科技》2023年第18期52-57,共6页Henan Science and Technology

基　　金：湖南省水利科技基金项目(XSKJ2022068-24)。

摘　　要：【目的】为研究素填土的填土特性对拱涵垂直土压力的影响。【方法】依托长沙市红旗渠排水改造工程,采用数值模拟的方法,探明了涵顶垂直土压力和涵顶平面填土沉降差随填土特性的变化规律,揭示了涵顶垂直土压力变化的内在成因,并利用正交试验对各影响因素进行敏感性分析。【结果】结果表明:涵顶垂直土压力与涵顶平面沉降差受填土高度、泊松比、压缩模量、内摩擦角的影响较大,受黏聚力的影响较小;涵顶垂直土压力系数随填土高度的增加先增大后减小并逐渐趋于平缓,且填土高度及压缩模量是对其影响最为敏感的因素,其次为内摩擦角和泊松比,黏聚力的敏感性最低。【结论】涵顶垂直土压力受填土特性与涵顶平面填土沉降差的共同影响,随着填土高度的增加,填土内部的土拱逐渐稳定,实际工程中可采用压缩模量较大、内摩擦角及泊松比较小的素填土,以减轻涵顶垂直土的压力。[Purposes]This paper aims to study the effect of fill characteristics of plain fill on the vertical earth pressure of arch culvert.[Methods]Relying on the Changsha Hongqi Canal drainage renovation project,numerical simulation was used to explore the change law of vertical soil pressure at the top of the culvert and the settlement difference of the plane fill at the top of the culvert with the characteristics of the fill,revealing the intrinsic causes of the change of vertical soil pressure at the top of the culvert,and the sensitivity analysis of each influencing factor was carried out by using orthogonal test.[Findings]The results show that the vertical earth pressure at the top of the culvert and the settlement difference of the plane at the top of the culvert are influenced by the height of the fill,Poisson′s ratio,compression modulus and internal friction angle are less influenced by the cohesion;the vertical soil pressure coeffi⁃cient at the top of the culvert increases with the increase of fill height and then decreases and tends to level off gradually,and the fill height and compression modulus are the most sensitive factors,followed by the internal friction angle and Poisson′s ratio,and the cohesion is the least sensitive.[Conclusions]The vertical earth pressure at the top of the culvert is affected by the joint influence of the fill characteris⁃tics and the settlement difference of the fill in the plane at the top of the culvert;as the height of the fill increases,the soil arch inside the fill is gradually stabilized,and the plain fill with larger compression modulus,smaller internal friction angle and Poisson′s ratio can be used in practical engineering to reduce the vertical soil pressure at the top of the culvert.

关 键 词：素填土 拱涵 土压力 数值分析 敏感性分析 正交试验 

分 类 号：U449[建筑科学—桥梁与隧道工程]