摘要
为了研究纤维与微生物诱导碳酸钙沉积(microbially induced carbonate precipitation,MICP)共同固化淤泥的抗剪强度特性,采用掺量为0、0.2%、0.4%、0.6%、0.8%玉米须纤维或碳纤维与MICP共同固化淤泥,对固化体进行直剪试验,借助扫描电镜,从微观的角度探讨了固化机理。结果表明:单掺纤维或利用MICP技术均可以提高固化体的抗剪强度,而MICP与纤维共同作用得到的固化体抗剪强度提高幅度更加显著。随着纤维含量的增加,固化体的黏聚力和内摩擦角先增加后减小,最佳纤维掺量为0.6%,纤维种类对内摩擦角影响无明显区别。由扫描电镜分析可知:纤维发生桥联作用将碳酸钙与土颗粒连接为一个整体,提高了土体抗剪强度;玉米须纤维较碳纤维表面更加粗糙且分散性好,体现出玉米须纤维加筋效果更好。
In order to study the shear strength characteristics of silt solidified by fiber and microbially induced carbonate precipitation(MICP)technology,the cured bodies were subjected to straight shear tests using cornsilk fiber or carbon fiber co-solidified with microorganisms at doping levels of 0,0.2%,0.4%,0.6%,0.8%,the direct shear test was carried out on the solidified silt,and the solidification mechanism was discussed from the microscopic perspective by scanning electron microscope.Results show that the shear strength of the solidified body can be improved by either adding fiber or using MICP technique,and the shear strength of solidified body obtained by the joint action of MICP and fiber is improved more significantly.With the increase of fiber content,curing the body of the cohesive and internal friction angle increase after the first decreases,the best fiber content is 0.6%and there is no significant difference in the effect of fiber types on the internal friction angle.Scanning electron microscope analysis show that the fiber bridging effect connects calcium carbonate and soil particles as a whole,which improves the shear strength of soil.Compared with carbon fiber,the surface of cornsilk fiber is rougher and has better dispersion,indicating that the reinforcement effect of cornsilk fiber is better.
作者
李赛
雷学文
刘磊
刘瑞琪
LI Sai;LEI Xue-wen;LIU Lei;LIU Rui-qi(College of Urban Construction, Wuhan University of Science and Technology, Wuhan 430065,China;State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics Chinese,Academy of Sciences,Wuhan 430071,China;Hubei Province Key Laboratory of Contaminated Sludge and Soil Science and Engineering, Wuhan 430071, China)
出处
《科学技术与工程》
北大核心
2021年第32期13837-13844,共8页
Science Technology and Engineering
基金
国家自然科学基金(U20A20320)。
