摘要
珊瑚砂在剪切过程中容易发生颗粒破碎,而颗粒破碎与应力水平、初始密度以及应力路径等因素有关。为了研究密度和应力水平对珊瑚砂颗粒破碎的影响,对珊瑚砂进行了三轴压缩试验和侧限压缩试验。文中建立了三轴压缩条件下颗粒相对破碎与围压和试样初始孔隙比之间的定量关系表达式,以及相对破碎与试样平均粒径之间的关系表达式。研究表明,在三轴压缩和侧限压缩条件下,试样的相对破碎均随着应力水平(围压或竖向应力)和试样密度的增大而增大,但两种应力路径下的颗粒破碎程度有显著的不同。
During the shearing process,coral sand is prone to particle breakage,which is related to stress level,initial density and stress path. In order to study the effect of density and stress level on the particles breakage of coral sand,triaxial compression tests and one-dimensional compression tests were carried out. In this paper,the quantitative relationship between the relative breakage of particles and the confining pressure and the initial void ratio of the specimen under triaxial compression is established,as well as the relationship between the relative breakage and the average particle size of the sample. The results show that,under triaxial compression and one-dimensional compression,the relative breakage increases with the increase of stress level(confining pressure or vertical stress) and sample density,but the degree of particle breakage under the two stress paths is significantly different.
引文
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