基于路基边坡柔性支护技术的膨胀土膨胀特性分析

Analysis of Expansion Characteristic of Expansive Soil Based on Flexible Supporting Structure of Expansive Soil Subgrade

膨胀土具有明显的干缩湿胀特性,其变形一旦受阻即产生膨胀力,导致公路路基边坡发生的严重破坏。柔性支护技术一举攻克膨胀土路基边坡的世界技术难题,为深入探究其工作机理并完善设计理论,迫切需弄清土体变形与膨胀力间相互作用关系。为此,本文进行了膨胀土相关试验,得到了土样竖、径向膨胀力并分析其随含水率、干密度的变化规律;研究了竖向膨胀力与径向膨胀力之关系及允许试件竖、径向少量变形时膨胀力的衰减;探讨了试验结果在柔性支护中的初步应用。

Expansive soils have obvious dry shrinkage and bulking, and its expansive force occurs once deformation is blocked, which results in the serious damage of highway structures. The flexible supporting technology solved the global technical problems of expansive soil sugared successfully. To deeply investigate its working mechanism and perfect the design theory, it is very necessary and exigent to find out the interaction relationship between soil deformation and expansive force. Therefore, this paper performs the experiment of expansive soil to get the expansibility of vertical and radial expansive force and analyzes the changing rule of the dry density and the moisture content, and researches the relationship of vertical expansion force and radial force and the expansive force attenuation when small vertical or radial deformation was allowed, and at the same time discusses the primary application of experiment result in flexibility supporting structure.