软土次固结特性试验研究

对广州南沙原状软土进行了一系列的固结试验，探讨了应力历史、加荷比、超载预压对软土次固结的影响。试验结果表明：软土的主次固结的划分与加荷比有关，加荷比对次固结系数C?也有影响；次固结系数主要受到先期固结压力pc的影响，当ppc时，次固结系数表现出不同的变化规律；经预压处理后土样的次固结系数与压缩指数Cc之比近似为一常数：C?/Cc≈0.03，试验成果所揭示的次固结特性对先期固结压力的依赖，为降低地基工后沉降提供了明确的思路。

Test study on properties of secondary consolidation of soft soil

Based on a series of consolidation tests for undisturbed samples in Guangzhou Nansha, the influence of stress history, load ratios and overload pre-pressure on secondary consolidation properties has been researched. The results show that the separation of primary consolidation and secondary consolidation is related to load ratios, which effect to secondary consolidation ratio C? also. Secondary consolidation was mainly affected by preconsolidation pressure pc. As p pc, C? presents different regularities. After preloading, the secondary consolidation ratio C? and compression index Cc is a constant: C?/Cc≈0.03. The test results indicate that character of secondary consolidation depends on preconsolidation pressure, which provides a perspicuity idea for reduce settlement after construction.