【摘要】 通过大量的室内模拟试验 ,对卸荷状态下的软粘土的抗剪强度进行研究 ,得到了不同先期固结压力下卸荷土体的τf-σ关系曲线 ,并与加荷状态的土体进行比较 ,得到了卸荷土体抗剪强度变化的一般规律 ;通过建立卸荷比 R和强度残留率 fr的概念来找寻影响卸荷土体抗剪强度变化的临界点 ;同时研究了卸荷土体的抗剪强度与卸荷比的关系、卸荷后滞留时间对卸荷土体抗剪强度的影响程度 ,发现卸荷土体的抗剪强度受卸荷比和卸荷后的滞留时间的影响很大。因此在卸荷工程中应充分重视以上两个因素对土体抗剪强度的影响更多还原

【Abstract】 In this paper, the shear strength of soft clayed\|soil is investigated in the condition of unloading through a great many laboratory scale\|down tests. By test statistics, the \$τ\-f\|σ\$ relationship of unloading soil at various preconsolidation pressures is described. By comparing with the soil in the state of loading, we can get the general rules of shear strength changes of soil in unloading. Furthermore, by using the unloading ratio (\$R\$) and strength residual ratio (\$f\-r\$),we can get the critical point in the shear strength changes of unloading soil. Meanwhile, in this paper, it is also mentioned the unloading ratio and the remaining time after unloading are greatly contributing to the shear strength changes of unloading soil. Therefore, close attention should be paid to these two factors in the unloading engineering.更多还原