超液限吹填黏土在主固结阶段的次固结特性试验研究

Secondary consolidation properties of dredger fill with over liquid limit at primary consolidation stage

对温州滨海重塑吹填黏土进行了一维固结试验,并将不同含水率、竖向荷载及反压条件得到的试验结果对比分析。研究表明:次固结沉降在主固结阶段便已经发生,且受有效应力持续时间和孔压水平联合影响。当试样含水率较低时,次固结开展主要受有效应力持续时间影响;而当含水率较高,远超液限时,次固结主要受孔压水平影响。并通过不同反压水平的固结试验,进一步验证了高孔压水平对次固结开展的促进作用。进而表明,孔压和位移两种固结度标准存在明显差异不仅源于压缩模量随有效应力增加,两种固结度受次固结影响程度不同也是造成差异的重要因素。

One-dimensional consolidation experiments are performed to study the secondary consolidation properties of remolded dredger soft soils from Wenzhou. The results show that the secondary consolidation occurs at the primary stage, and is influenced by both effective stress and pore pressure potential. When the moisture content is rather low, the former is the dominatant element, However, when the moisture content is much higher than the liquid limit, the latter is the dominatant element. The development of the secondary consolidation promoted by high pore pressure is further verified through the consolidation tests with different back pressure levels. Therefore, the secondary consolidation has different influences on the evolution of pore pressure and deformation. It causes the distinction between the consolidation degrees of pore pressure and deformation, as well as the compressive modulus changing with the effective stress.