含水率对根-土石复合体抗剪强度影响的试验研究——以垂丝海棠为例
Experimental Study on the Influence of Water Content on the Shear Strength of Root-Soil-Rock Composite——A Case Study of Malus halliana
陶首仲 1周花玉 2张卓超 1樊东升 1郑峰 1刘含霞 1周张路 1刘建平1
作者信息
- 1. 四川农业大学水利水电学院,四川 雅安 625014
- 2. 中国市政工程中南设计研究总院有限公司,武汉 430010
- 折叠
摘要
[目的]探究含水率对根-土石复合体抗剪强度的影响规律.[方法]以四川农业大学雅安校区老板山典型固坡植物垂丝海棠为研究对象,固定剪切面含根量为0.2%、含石量为30%,设置5种含水率梯度(10%、15%、20%、25%、30%),分别在50、100、150和200 kPa的四级正应力下进行室内直接剪切试验,分析含水率对抗剪强度及其指标(黏聚力和内摩擦角)的影响规律.[结果]根-土石复合体的抗剪强度随正应力的增大而增高,符合莫尔-库伦强度准则,其抗剪强度随含水率的升高呈先下降后上升随之再下降的趋势,呈多峰曲线变化,在含水率为20%时取得最小值;含水率对根-土石复合体的黏聚力影响较大,在含水率为25%时取得临界峰值,但含水率对根-土石复合体的内摩擦角影响较小.[结论]含水率的变化主要影响根-土石复合体的黏聚力,从而影响根-土石复合体的峰值抗剪强度,而对内摩擦角的影响较小.研究结果可为植被加固土石混合体边坡提供一定的理论支撑.
Abstract
[Objective]The aim of this study is to investigate the effect of water content on the shear strength of root-soil-rock composite.[Method]This study was conducted on Malus halliana,a typical slope stabilization plant on the Laoban Mountain of Yaan campus,Sichuan Agricultural University.Five gradiants of water content(10%,15%,20%,25%,30%)were set on a fixed shear surface with root content of 0.2%and stone content of 30%.Direct shear tests were carried out with four different normal stresses of 50,100,150 and 200 kPa.The influence of water content on the shear strength and its in-dexes(cohesion and internal friction angle)were analyzed.[Result]The shear strength of the root-soil-rock composite increased with the rising of normal stress,suggesting adherence to the Mohr-Coulomb strength criterion.Additionally,the shear strength of the composite decreased first,then increased and followed by a decrease with the increase of water content,characterized by a multi-peak curve pattern with a minimum value observed at 20%water content.The cohesion of the root-soil-rock composite was affected by the water content significantly,and reaching a critical peak at 25%.In contrast,the internal friction angle of the root-soil-rock composite showed minimal variation with changing water content.[Conclusion]The change of water content primarily affects the cohesion of the root-soil-rock compos-ite,and thus influence the peak shear strength while having minimal impact on the internal friction angle.The findings of this study could provide theoretical support for the reinforcement of soil-rock mixture slope through vegetation.
关键词
边坡工程/根-土石复合体/含水率/抗剪强度/垂丝海棠Key words
slope engineering/root-soil-rock composite/water content/shear strength/Malus halliana引用本文复制引用
基金项目
国家自然科学基金(41907242)
国家级大学生创新创业训练计划(2221998240)
国家级大学生创新创业训练计划(2321998131)
出版年
2024
NETL
NSTL
万方数据