纤维-水溶性聚合物加固砂土抗剪强度特性试验研究  

Experimental study on shear strength of fiber-water soluble polymer composite modified sand

作　　者：朱旭芬[1] 郑加强 魏继红[1] 张成祥 马柯 冯玉晗 张晨阳 祁长青[1] ZHU Xufen;ZHENG Jiaqiang;WEI Jihong;ZHANG Chengxiang;MA Ke;FENG Yuhan;ZHANG Chenyang;QI Changqing(School of Earth Sciences and Engineering,Hohai University,Nanjing 211100,China)

机构地区：[1]河海大学地球科学与工程学院,江苏南京211100

出　　处：《水利水电科技进展》2023年第6期50-59,共10页Advances in Science and Technology of Water Resources

基　　金：国家自然科学基金项目(41877212)。

摘　　要：为了解纤维-水溶性聚合物的抗剪强度和砂土的破坏机理,通过一系列直剪试验和数值模拟,研究了不同水溶性聚合物含量和纤维含量条件下加固砂土的剪切强度特性,分析了加固砂土的抗剪强度特性及其参数变化和破坏特征。试验结果表明:加固砂土的抗剪强度特性随水溶性聚合物含量和纤维含量的增大而显著提高;水溶性聚合物和纤维的掺入提升了加固砂土的黏聚力,但对内摩擦角的影响较小;当纤维含量为0.8%时,水溶性聚合物含量从1%增大至4%,加固砂土的抗剪强度增强了55.58 kPa;当水溶性聚合物含量为4%时,纤维含量从0.2%增大至0.8%时,黏聚力增加了32.69 kPa。聚合物和纤维含量的增大促进了复合砂土各组分之间的联合,增强了加固砂土的整体性,提升了土体的稳定性。In order to study the shear strength of fiber-water soluble polymer composite and the failure mechanism of sand,the shear strength characteristics of improved sand under different polymer contents and fiber contents were studied through a series of direct shear tests and numerical tests.The shear strength,parameters and failure characteristics of improved sand were analyzed.The test results show that the shear strength characteristics of the improved sand increase significantly with the polymer content and fiber content.The incorporation of water-soluble polymers and fibers increases the cohesion and has little fluence on the internal friction angle of the improved sand.When the fiber content is 0.8%and the water-soluble polymer content increases from 1%to 4%,the shear strength of the improved sand increases by 55.58 kPa.When the water-soluble polymer content is 4%and the fiber content increases from 0.2%to 0.8%,the cohesion increases by 32.69 kPa.The increase in polymer and fiber contents promotes the bonding between the components of the composite sandy soil,enhances the overall integrity of the improved sandy soil,and improves the stability of the soil.

关 键 词：加固砂土 水溶性聚合物 聚丙烯纤维 直剪试验 数值模拟 

分 类 号：TU411.7[建筑科学—岩土工程]