聚丙烯纤维对固化工程废浆压缩性能和渗透性能的影响

Effect of Polypropylene Fiber on Compression Behavior and Permeability of Cemented Construction Waste Slurry

通过对聚丙烯纤维加固的固化工程废浆开展室内一维压缩试验和柔性壁渗透试验,研究固化高含水率工程废浆压缩性能和渗透性能随纤维掺量(0%~1.2%,质量分数,下同)和纤维长度(3~18 mm)的变化规律,探讨纤维添加引起固化工程废浆力学性能变化的原因。结果表明,当纤维掺量为0.5%时,纤维添加会引起固化工程废浆体应变和渗透系数减小。此时,对于初始含水率为145%的固化工程废浆,纤维添加引起其体应变的降低幅度随纤维长度的增加而减小。当初始含水率增加至174%时,纤维添加引起固化泥浆体应变的降低幅度则基本不受纤维长度增加的影响;当纤维掺量较高(1.2%)时,和短纤维(<12 mm)相比,相同外加荷载下含长纤维固化工程废浆的体应变和渗透系数增大。对于研究所用工程废浆,聚丙烯纤维的长度和掺量分别以不超过12 mm和1.2%为宜。

One-dimensional compression tests and permeability tests were conducted to investigate the effects of fiber content(0%to 1.2%,mass fraction,the same below)and length(3 mm to 18 mm)on compression behavior and permeability of cemented construction waste slurry with high water content.The related mechanisms responsible for changes caused by addition of polypropylene fiber were discussed.The test results indicate that the addition of fiber induces a decrease in the volumetric strain and permeability coefficient of cemented construction waste slurry with 0.5%fiber.Meanwhile,the reduction in the volumetric strain decreases with the increase of the fiber length when the initial water content of tested specimen is 145%,and there is no significant influence of the fiber length on the volumetric strain of specimens with initial water content of 174%.On the other hand,an increase in the volumetric strain and permeability coefficient is observed for specimens with longer fiber than short fiber(<12 mm)under the same external pressure as the fiber content increases to 1.2%.In this research,the appropriate fiber length and content is not more than 12 mm and 1.2%,respectively.