摘要
颗粒破碎现象对土体力学性能具有显著影响。以往关于颗粒破碎的研究多关注于粒径的变化,忽视了颗粒形状的变化。为研究破碎过程中颗粒形状的演化规律,开展了钙质砂和石英砂的侧限压缩试验,对试验过程中颗粒形状参数的进行了量化研究。结果表明两种砂土的相对破碎率均随着单位体积塑性功的增加而增加,表现出明显的双曲线关系。钙质砂的长径比、球形度和圆度会随着破碎程度的增加而增加,凸度变化不明显;随破碎量的增加,石英砂颗粒的长径比和球形度先减少后增加,凸度持续减少至稳定,球形度持续增加。通过定义试样整体的形状值能很好的量化颗粒形状的变化规律。并且钙质砂整体形状值与相对破碎率满足双曲线关系,石英砂则为抛物线关系。
The influences of particle breakage on the mechanical properties of soil are significant.The previous studies mainly focus on the variation of particle size during particle breakage but neglect the change of particle shape.In order to study the evolution of particle breakage,a series of one-dimensional compression experiments are carried out with calcareous sand and quartz sand,and the changes of particle shape are quantified.The results show that the relative breakage index of the two sands increases with the increase of plastic work per unit volume with an obvious hyperbolic relationship.The aspect ratio,sphericity and roundness of the calcareous sand increase with the expanded breakage,but the variation of convexity is unobvious.For the quartz sand,the aspect ratio and sphericity decrease first and then increase,while the convexity decreases to be stable and the sphericity continues to increase.This trend can be well quantified by defining the overall shape value of the samples.In addition,the overall shape value of the calcareous sand shows a hyperbola relationship with the relative breakage,and that of the quartz sand shows a parabola relationship.
作者
孙越
肖杨
周伟
刘汉龙
SUN Yue;XIAO Yang;ZHOU Wei;LIU Han-long(School of Civil Engineering,Chongqing University,Chongqing 400045,China;Key Laboratory of New Technology for Construction of Cities in Mountain Area,Chongqing University,Chongqing 400045,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2022年第6期1061-1068,I0005,I0006,共10页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金优秀青年项目(51922024)
国家自然科学基金面上项目(52078085)
重庆市自然科学基金杰出青年项目(cstc2019jcyjjqX0014)。
关键词
颗粒破碎
形状演化
钙质砂
石英砂
侧限压缩
particle breakage
shape evolution
calcareous sand
quartz sand
one-dimensional compression
