贝壳砂颗粒破碎及抗剪强度研究

On grain breakage and shear strength of shell sand

对贝壳砂的的破碎机抗剪强度进行了系统的研究。在原有颗分曲线的形式上,对其进行创新,提出了相对颗分曲线,能够直观地反映出颗粒破碎过程中某一粒径内颗粒含量的变化,也能较为简单地表达出颗粒破碎程度。此外,对贝壳砂的固结排水和不排水强度进行了系统的分析,指出在颗粒破碎过程中,粘聚力对颗粒破碎的影响较内摩擦大,而在应力应变过程中,内摩擦角对峰值应力的影响占据了主动地位。当相对密度及围压相同时,固结排水达到峰值应力差要比固结不排水大很多。

The grain breakage and shear strength of shell sand are studied systematically. Based on the innovation of former grain size distribution curve, a new curve of relative grain size distribution curve is put forward, which reflects directly the change of the grain content in one grain size in the process of grain＇s breakage and shows the degree of particle＇s breaking briefly. Moreover, the triaxial compression consolidated undrained （CU） tests and drained （CD）tests are analyzed systemically. It points out that the cohesion has more effect on the grain＇s breakage than the internal friction angle in the process of grain＇s breakage, whereas the internal friction angle takes the initiative to peak stress in the process of strain-stress. When the relative density and confining pressure phase are equal during the test, the peak stress of CD is higher than CU.