碳酸钙含量对钙质砂性质影响的室内试验研究  

Indoor experimental study of the effect of calcium carbonate content on properties of calcareous sand

作　　者：李飒[1] 刘富诗 戴旭 张彦龙 LI Sa;LIU Fu-shi;DAI Xu;ZHANG Yan-long(Geotechnical Institute,Civil Engineering Department,Tianjin University,Tianjin 30072,China;China Railway Liuyuan Group Co.,Ltd.,Tianjin 300308,China;Tianjin Traffic Science Research Institute,Tianjin 300300,China)

机构地区：[1]天津大学建工学院岩土所,天津300072 [2]中铁第六勘察设计院集团有限公司,天津300308 [3]天津市交通科学研究院,天津300300

出　　处：《实验力学》2019年第1期88-94,共7页Journal of Experimental Mechanics

基　　金：国家自然科学基金重点项目(51239008);国家自然科学基金(51379145);高技术船舶科研计划2016[22]

摘　　要：通过室内试验的方法,研究了碳酸钙(CaCO3)含量变化对钙质砂的颗粒破碎和宏观力学特性的影响。试验结果表明:取自南海海域的钙质砂样碳酸钙含量为95.8%,并表现出高孔隙、棱角明显等特征。钙质砂颗粒破碎本质上是颗粒间应力集中的表现,随着碳酸钙含量的增加、粒径的增大,钙质砂的内摩擦角和相对破碎率明显增加;颗粒破碎导致级配曲线向良好的方向发展,同时,引起较高应力条件下的强度包线具有非线性的特征。相对破碎率随正应力和碳酸钙含量的变化规律可用一组二元双曲线函数关系式表示。The influence of calcium carbonate content on particle breakage and macroscopic mechanical properties of calcareous sand was systematically studied by indoor experiment.Experimental results show that the calcium carbonate content of the calcareous sand taken from the South China Sea is 95.8% and the calcareous sand is characterized by the angularity,and high void ratio.The breakage of calcareous sand is essentially result from stress concentration between particles;with the increase of calcium carbonate content and particle size,the friction angles and relative breakage index of calcareous sand increase significantly.Particle breakage not only leads to the particle size distribution into good gradation,but also caused the shear strength envelope expressed nonlinear characteristic under higher normal stress;and with the change of the normal stress and the calcium carbonate content,a set of two variables hyperbola function can be used to describe the change rule of relative breakage index.

关 键 词：钙质砂 碳酸钙含量 颗粒破碎 抗剪强度 室内试验 

分 类 号：TU521.1[建筑科学—建筑技术科学]