钙质砂声发射特征的三轴试验研究  

Triaxial experiment study of acoustic emission laws of calcareous sand

作　　者：陈清运[1] 孙吉主[2] 汪稔[3] 

机构地区：[1]武汉工程大学,武汉430073 [2]武汉理工大学土建学院,武汉430070 [3]中国科学院武汉岩土力学研究所,武汉430071

出　　处：《岩土力学》2009年第7期2027-2030,2036,共5页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No40402024)

摘　　要：钙质砂在低应力水平下就会产生颗粒破碎,并伴随有明显的声发射。在不同围压下,对不同初始孔隙比和级配的南沙群岛永暑礁钙质砂进行室内三轴排水剪切试验,同时监测其声发射信号。试验发现:当围压增加或初始孔隙比减小时,钙质砂偏应力峰值逐渐增加,但在某一界限围压时,声发射活动出现最强,在某一界限孔隙比附近时,声发射活动出现最弱;对于级配较差的钙质砂,试验前期声发射活动较弱,其偏应力峰值较小。Particle breakage of calcareous sand occurs at lower stress level, and it results in stronger acoustic emission （AE）. Triaxial shear tests on calcareous sand at Yongshu reef of Nansha islands are carried with different confining pressure, initial pore ratio and grain gradation, at the same time AE signals from sand are monitored. Test results show when confining pressure increases or initial pore ratio decreases, deviator stress peak value increase gradually, but AE is the strongest or weakest at some confining pressure or pore ratio limit individually; if the gradation of calcareous sand is poorer, its AE is weaker at the beginning of test; and deviator stress oeak value is also smaller.

关 键 词：钙质砂 声发射 三轴试验 

分 类 号：TU411[建筑科学—岩土工程]