珊瑚砂抗剪强度及颗粒破碎影响因素试验研究  

Experimental study of influencing factors of shear strength and particle breakage of coral sand

作　　者：娄昕骐 刘文化[1,2] 李吴刚 LOU Xinqi;LIU Wenhua;LI Wugang(Institute of Geotechnical Engineering,Dalian University of Technology,Dalian 116024,China;School of Environment and Civil Engineering,Jiangnan University,Wuxi 214122,China)

机构地区：[1]大连理工大学岩土工程研究所,辽宁大连116024 [2]江南大学环境与土木工程学院,江苏无锡214122

出　　处：《大连理工大学学报》2024年第4期384-392,共9页Journal of Dalian University of Technology

基　　金：国家自然科学基金资助项目(52009049,51709129)。

摘　　要：珊瑚砂质脆易破碎,其力学与变形特性有别于石英砂.为研究粒径、预压缩对珊瑚砂抗剪强度及颗粒破碎的影响,对珊瑚砂试样进行了侧限压缩试验与三轴剪切试验.同时探讨了珊瑚砂-石英砂混合物在三轴剪切状态下的力学和变形特性.结果表明,破碎后的珊瑚砂颗粒主要集中在较原粒径小一级的粒径中;初始粒径越小,颗粒团簇现象越明显;粒径对颗粒破碎影响较大,大于1 mm粒径的珊瑚砂颗粒破碎尤为明显;破碎后的珊瑚砂颗粒粒径主要集中在大于0.25 mm的范围内.预压缩(颗粒破碎)会导致珊瑚砂内摩擦角增大,掺入石英砂对珊瑚砂内摩擦角影响很小,预压缩和掺入石英砂都会减小珊瑚砂的假黏聚力,石英砂掺量越多,假黏聚力降低越明显;预压缩、增加石英砂掺量和增大粒径都会减小颗粒团簇程度,同时增大颗粒破碎程度.Coral sand is brittle and easily broken,and its mechanical and deformation properties are different from those of quartz sand.To study the influence of particle size and precompression on the shear strength and particle breakage of coral sand,the confined compression test and triaxial shear test are carried out on coral sand samples.The mechanical and deformation properties of coral sand-quartz sand mixture in triaxial shear state are discussed.The results show that the crushed coral sand particles are mainly concentrated in the particle size one level smaller than the original particle size.The smaller the initial particle size is,the more obvious the particle clusters are.The particle size has a great influence on particle breakage,especially when the particle size of coral sand is larger than 1 mm.The particle size of coral sand after crushing is mainly greater than 0.25 mm.Precompression(particle breakage)will lead to the increase of coral sand internal friction angle.The addition of quartz sand has little effect on the internal friction angle.Both precompression and the addition of quartz sand will reduce the apparent cohesion,and the more the content of quartz sand is,the more the apparent cohesion decreases.Precompression,increasing the content of quartz sand and increasing the particle size will reduce the degree of particle clusters and increase the degree of particle breakage.

关 键 词：珊瑚砂 颗粒破碎 抗剪强度 侧限压缩试验 三轴剪切试验 

分 类 号：TU441[建筑科学—岩土工程]