石灰改良土抗剪强度影响因素的试验研究

以上海某新建工程路段的石灰改良软黏土开展动三轴试验，研究掺灰量、围压及含水量对其抗剪强度及有效抗剪强度参数的影响。结果表明:石灰改良土强度随着围压和掺灰量的增加而增加，随着含水量的增加而减小；随着掺灰量的增加，石灰改良土有效黏聚力增加，有效内摩擦角减小。掺灰量对于抗剪强度参数的影响存在一个临界值:掺灰量为3%的石灰改良土有效内摩擦角最大；掺灰量为6%～9%时，石灰改良土的有效内摩擦角和有效黏聚力保持相对稳定状态；掺灰量超过9%时，石灰改良土的有效黏聚力增加和有效内摩擦角减小都较为明显。

Experimental Study on Influencing Factors of Shear Strength of Lime Improved Soil

In this paper, the dynamic triaxial test was carried out for the lime improved soft clay of a newly built project in Luobei Road in Shanghai to study the influence of lime content, confining pressure and water content on its shear strength and effective shear strength parameters. The results show that the strength of lime improved soil increased with the increase of confining pressure and lime content and decreased with the increase of water content; with the increase of lime content, the effective internal cohesion of lime improved soil increased and the effective internal friction angle decreased. In the mean time, the lime content has a critical value to influence the shear strength parameters. When the lime content is 3%, the effective internal friction angle of the lime improved soil is the biggest; when the lime content changes from 6% to 9%, the effective internal friction angle and the effective internal cohesion are relatively stable; when the lime content exceeds 9%, the effective internal cohesion is increased and the effective internal friction angle decreased significantly.