摘要
利用改进的三轴实验仪,开展了麦堆三轴剪切实验,研究了剪切速率对剪切应力应变及体变应变的影响,获得了剪切速率对麦堆内摩擦角、剪胀角的影响规律.研究结果表明:不同剪切速率、不同围压下麦堆剪切应力应变及应变体变曲线类似.随着轴向应变增加剪切应力逐渐增加,达到剪切强度峰值后呈现一定的软化现象;随着轴向应变增加,体变应变曲线表明麦堆的剪切发生由剪缩到剪胀的变化过程.剪切速率影响麦堆峰值剪切强度及体变应变曲线均有影响,剪切速率越大,内摩擦角越小,剪胀角越小.获得的不同剪切速率下麦堆内摩擦变化范围为23.2°~24.7°,剪胀角为5.6°~14.8°.根据实验结果,麦堆合理的三轴剪切速率为0.2~0.5 mm/min.
The stress-strain behavior and the volume-strain of wheat at different shearing velocities were investigated by using a modified triaxial drained shear tests.The effects of shearing velocity on angle of internal friction,apparent cohesion and dilatancy angle were discussed in this paper.The results indicated that axial stress-axial strain curves and volumetric strain-axial strain curves exhibited the similar characters under different shearing velocities and normal stresses.The axial stress-strain curves exhibited various degrees of softening with the increase of axial strain.The volumetric strain-axial strain curves showed the transfer from volume contraction to dilatancy.The shearing velocities had effects on both the shear strength and volumetric change behavior.The internal frictional angle ranged from 23.3°to 24.6°.The dilatancy angle changed from 5.6°to 14.8°in the range of testing velocity.The shearing velocity of 0.2 to 0.5 mm/min was recommended according to the test results.
作者
曾长女
田彦歌
宋飞如
Zeng Changnü;Tian Yange;Song Feiru(School of Civil Engineering,Henan University of Technology,Zhengzhou450001)
出处
《中国粮油学报》
EI
CAS
CSCD
北大核心
2020年第7期131-136,共6页
Journal of the Chinese Cereals and Oils Association
基金
河南省高等学校重点科研项目计划(19A560009)
河南省粮油仓储建筑与安全重点实验室开放基金(2016KF-B03)
河南工业大学青年骨干教师资助计划(2015004)
国家自然科学基金(51108160)。
关键词
三轴剪切
剪切速率
强度体变
剪胀性
triaxial drained test
shearing rate
strength volumetric strain
dilatancy
作者简介
曾长女,女,1978年出生,教授,粮仓与地基相互作用。
