摘要
橡胶土都是一种常用的减震材料,但是强度较低。采用MICP技术胶结掺入3%以内的橡胶粉末砂土,试验研究了微生物胶结后橡胶砂土单轴抗压强度、循环加卸载作用特性及其微观结构。研究表明微生物胶结后横波波速和试样密度随橡胶含量增加而增加,其单轴抗压强度变化不大,受橡胶含量影响较小。随加卸载循环次数增加,微生物胶结橡胶粉末砂土阻尼比和滞回环面积逐渐减小,但是其刚度变化较小。相同加卸载循环次数条件下,微生物胶结橡胶粉末砂土阻尼比、滞回曲线面积及其刚度随橡胶粉末含量增加而增加。在微生物胶结橡胶粉末砂土中砂土胶结颗粒间,橡胶粉末与碳酸钙晶体形成了具有一定微观强度的蜂窝孔状结构,有利于缓冲砂颗粒在外界动荷载作用的位置变动,吸收砂颗粒传递过来的能量,从而起到减震作用。
Rubber soil is a kind of common damping material,but its strength is low.By using MICP technology to cement sand with less than 3%rubber powder,the paper experimentally studies the uniaxial compressive strength,cyclic loading and unloading characteristics and microstructure of rubber sand after microbial cementation.The results show that after microbial cementation,the shear wave velocity and sample density increase with the increase of rubber content,and its uniaxial compressive strength does not change much,which is less affected by the rubber content.With the increase of the number of loading and unloading,the damping ratio and the loop area of hysteresis of the microbial cemented rubber powder sand gradually decrease,but the stiffness change is small.Under the same loading and unloading cycles,the damping ratio,the area of hysteresis loop and the stiffness of microbial cemented rubber sand increases with the increase of the content of rubber powder.Among the sand cemented particles in the microbial cemented rubber powder sand,the rubber powder and calcium carbonate crystal form a honeycomb structure with certain micro-strength,which is beneficial to buffer the position change of the sand particles under the external dynamic load and absorb the energy transferred from the sand particles,and thus play a shock absorption effect.
作者
尤浩
王伟岩
陶元洪
李沛
周启文
YOU Hao;WANG Weiyan;TAO Yuanhong;LI Pei;ZHOU Qiwen(CCCC First Harbor Engineering Co.,Ltd.,Tianjin 300461,China;CCCC Tianjin Port Engineering Institute Co.,Ltd.,Tianjin 300222,China;School of Resources and Safety Engineering of Central South University,Changsha 410083,China)
出处
《华南地震》
2021年第3期26-32,共7页
South China Journal of Seismology
基金
国家自然科学基金项目(51508579,51674287)。
