摘要
为探究干湿循环效应对纤维膨胀土抗剪强度的影响,进行了大量的干湿循环和直剪试验。纤维含量按0%,0.1%,0.2%.0.3%,0.4%来设计,干湿循环次数为0~6次。试验结果表明:①随着干湿循环次数的逐渐增加,内摩擦角先是小幅度提高,然后逐渐减小并趋于稳定;随着干湿循环次数的逐渐增加,黏聚力则是逐渐减小并趋于稳定,其衰减规律基本符合二次函数;②随着干湿循环次数的增加,抗剪强度逐渐减小,在干湿循环1—3次的时候衰减幅度较大;之后逐渐减小并趋于稳定;③适当的增加上覆荷载,能够有效地抑制纤维膨胀土在干湿循环过程中强度的衰减。综合比较干湿循环效应对纤维膨胀土内摩擦角和黏聚力的影响,当纤维含量在0.3%时,对纤维膨胀土在干湿循环过程中抑制抗剪强度的衰减作用明显。
To study the impact that the wet-dry cycles cause on the strength of expansive soil and fiber expansive soil, a large number of wet-dry cycles and direct shear test were carried out. Before the shear tests, fiber content by 0%, 0. 1%, 0. 2%, 0. 3%, 0.4% to design, dry-wet cycles of 0 - 6 times. The experimental results showed that: ①with the gradual increase in the wet-dry cycles, internal friction angle slight increase first, and then gradually decreased and stabilized ; With the gradual increase in the number of cycles of wet-dry, the cohesion is gradually reduced and stabilized, the attenuation of line with a quadratic function ; ②with the increase of the wetdry cycles, shear strength decreased Seriously, and then gradually decreased and stabilized; ③ an appropriate in- crease in the cover load could effectively suppress the attenuation of strength caused by wet-dry cycles in fiber expansive soil. When the fiber content was 0.3% , the attenuation of shear strength induced by wet-dry cycles could be effectively alleviated, comparing the effects of friction angle and cohesion of fiber expansive soil in wet-dry cycles synthetically.
出处
《科学技术与工程》
北大核心
2015年第19期175-179,共5页
Science Technology and Engineering
关键词
干湿循环
膨胀土
纤维
抗剪强度
wet-dry cyclesexpansive soil fiber shear strength