摘要
文章研究二次纤维掺量对不同养护时间下水泥土力学性质的影响规律。为强化水泥土力学性质使其更广泛应用于工程建设,同时探究废纸资源回收再利用新途径,以废纸降解获得的二次纤维作为外加剂,通过直剪试验对比分析素土、普通水泥土和二次纤维掺量分别为2%、4%、6%的水泥土在养护7d、14d和28d下的抗剪强度特征。结果表明:(1)二次纤维掺量为4%的水泥土经过养护后抗剪强度均高于普通水泥土,而二次纤维掺量为2%的水泥土在养护7d和14d时抗剪强度高于普通水泥土;(2)添加2%的二次纤维可以使普通水泥土在养护7d和14d时,粘聚力分别提高4%和27.1%,添加4%的二次纤维可以使普通水泥土在养护28d时,粘聚力提高2倍;(3)养护时间从14d增加到28d时,普通水泥土粘聚力下降54%,二次纤维掺量为2%和4%的水泥土粘聚力仅下降42%和6%;(4)养护7d和14d时,添加二次纤维使水泥土内摩擦角增大;养护28d时,纤维分解,导致水泥土内摩擦角减小;(5)养护28d时,水泥土的粘聚力和内摩擦角与二次纤维掺量呈现明显的抛物线和倒抛物线关系。
The influence of secondary fiber content on the mechanical properties of cement soil under different curing time is studied.In order to strengthen the mechanical properties of cement soil and make it more widely used in engineering construction,and to explore a new way of recycling waste paper resources,the secondary fiber obtained from waste paper degradation is used as an additive.Through direct shear test,the shear strength characteristics of plain soil,ordinary cement soil and cement soil with 2%,4%and 6%of secondary fiber content are compared and analyzed under 7 d,14 d and 28 d of curing.The results show that(1)the shear strength of cement soil with 4%secondary fiber content is higher than that of ordinary cement soil after curing,and the shear strength of cement soil with 2%secondary fiber content is higher than that of ordinary cement soil after curing for 7 d and 14 d;(2)adding 2%secondary fiber can improve the cohesion of ordinary cement soil by 4%and 27.1%respectively after curing for 7 d and 14 d,and adding 4%secondary fiber can make the cohesion of ordinary cement soil increase by 4%and 27.1%respectively When the cement soil was cured for 28 d,the cohesion increased by 2 times;(3)when the curing time increases from 14 d to 28 d,the cohesion of cement soil decreases by 54%,and the cohesion of cement soil with 2%and 4%secondary fibers decrease only by 42%and 6%;(4)when the cement soil is cured for 7 d and 14 d,the internal friction angle of water soil increases with the addition of secondary fibers,and when the cement soil is cured for 28 d,the fiber is decomposed,which resulting in the decrease of internal friction angle of cement soil;(5)when the cement soil is cured for 28 d,the cohesion and internal friction angle of cement soil have obvious parabola and reverse parabola relationship with the content of secondary fiber.
作者
张明飞
王立娜
徐永浩
饶碧玉
ZHANG Ming-fei;WANG Li-na;XU Yong-hao;RAO Bi-yu(School of Architecture and Civil Engineering,Yunnan Agricultural University,Kunming 650201,China;Southwest Survey and Design Group Co.,Ltd China Railway Siyuan Group,Kunming 650200,China)
出处
《内蒙古大学学报（自然科学版）》
CAS
北大核心
2020年第3期329-336,共8页
Journal of Inner Mongolia University：Natural Science Edition
基金
云南省科技厅应用基础研究面上项目(2018FB075)
云南农业大学学生科技创新创业基金项目(2019KFY030)。
关键词
水泥土
废纸
二次纤维
抗剪强度
粘聚力
内摩擦角
cement soil
waste paper
secondary fiber
shear strength
cohesion
internal friction angle
