循环荷载作用下剑麻纤维加筋砂残余变形及刚度变化分析  

Analysis of Residual Deformation and Stiffness Variation of Sisal Fiber Reinforced Sand Under Cyclic Loading

作　　者：张梦子 刘春辉 钟汉林 ZHANG Meng-zi;LIU Chun-hui;ZHONG Han-lin(School of Civil Engineering,Yantai University,Yantai 264005,China)

机构地区：[1]烟台大学土木工程学院,山东烟台264005

出　　处：《烟台大学学报（自然科学与工程版）》2022年第1期108-113,共6页Journal of Yantai University(Natural Science and Engineering Edition)

基　　金：国家自然科学基金资助项目(51908484,51808478);山东省自然科学基金资助项目(ZR2019BEE039,ZR2019QEE033);中国地震局工程力学研究所基本科研业务费专项资助项目(2019D09,2018D15);黑龙江省地下工程技术重点实验室开放基金资助项目(HXYKF-2019-05)。

摘　　要：通过一系列动三轴试验,研究了循环应力水平和围压对纤维加筋砂变形与刚度的影响,分析了不同围压和应力幅值条件下,纤维加筋砂的残余轴向应变、残余体积应变以及动态杨氏模量的动态响应规律。试验结果表明:随着循环应力水平的提高,残余轴向应变的发展呈现出塑性安定、塑性蠕变与塑性破坏3种不同的机制;应力幅值越大,残余轴向应变和残余体积应变增长越快;动态杨氏模量在小应变范围内保持恒定,一旦超过应变阈值,动态杨氏模量随着应变的增加而降低。By a series of dynamic triaxial tests,the effects of cyclic stress and confining pressure on the deformation and stiffness of fiber-reinforced sand are studied,and the dynamic response of residual axial strain,residual volumetric strain and dynamic Young's modulus are analyzed under different levels of confining pressure and stress amplitude.It is shown that,the development of residual axial strain presents three different mechanisms,namely plastic shakedown,plastic creep and plastic failure,under increasing cyclic stress.The residual axial strain and residual volumetric strain increase faster with the increasing of stress amplitude,while dynamic Young's modulus remains constant in a small strain range and decreases with the increase of strain over a threshold value.

关 键 词：剑麻纤维 加筋砂 循环三轴试验 残余应变 刚度 

分 类 号：TU472.2[建筑科学—结构工程]