长沙理工大学学报（自然科学版）2023，Vol.20Issue(6)：1-16,16.DOI:10.19951/j.cnki.1672-9331.20220716001
膨胀土强度特性的研究进展与探究
Research progress and exploration on strength characteristics of expansive soil
摘要
Abstract
[Purposes]The study is to further study the influencing factors of shear strength of expansive soil and explore the mechanism of the most essential swelling-induced characteristics of expansive soil on shear strength.[Methods]On the basis of summarizing the main research results on the shear strength characteristics of expansive soil at home and abroad,this article categorized the influencing factors of the shear strength of expansive soil into three special properties:swelling shrinkage,cracking,and overconsolidation.Based on the theory of unsaturated soil shear strength,a scientific hypothesis was made regarding the changes in effective shear strength indicators of expansive soil before and after swelling,and experimental verification was conducted using an improved direct shear test device and a laser particle size analyzer.[Findings]The variation of shear strength of expansive soil is closely related to its three special properties;In the saturated direct shear test,the effective cohesion and effective internal friction angle both decrease hyperbolically with the decrease of dry density;After swelling,the content of particles with a particle size below 0.1 mm increases significantly,and the greater the dry density,the greater the cumulative content change.[Conclusions]The micro mechanism of strength attenuation in expansive soil is due to the fragmentation and separation of solid particles in expansive soil under the action of lattice swelling,resulting in changes in particle gradation.This is an important factor causing differences in strength indicators.关键词
道路工程/膨胀土/抗剪强度/胀缩性/裂隙性/超固结性Key words
road engineering/expansive soil/shear strength/swelling and contraction/fissure/overconsolidation分类
交通工程引用本文复制引用
凌时光,张锐,兰天..膨胀土强度特性的研究进展与探究[J].长沙理工大学学报（自然科学版）,2023,20(6):1-16,16.基金项目
国家自然科学基金资助项目(51978085) Project(51978085)supported by the National Natural Science Foundation of China （51978085）
