天津滨海软土固结-蠕变特性及微观结构分析

Study on the consolidation-creep characteristics and microstructure of the soft soil in Tianjin Binhai Area

本文以天津滨海软土为研究对象,运用室内试验、微观分析等手段,并采用宏微观结合的方法对结构性软土的蠕变特性进行了研究。试验结果表明:天津滨海软土蠕变特性显著,且蠕变有明显的非线性特征;通过对原状土和重塑土的蠕变试验结果曲线对比分析,表明软土的结构对其蠕变特性具有显著影响;原状土体疏松的片架结构、颗粒的边—面接触以及发育的孔隙是土体具有显著蠕变特性的内在原因,蠕变稳定后土体结构密实程度提高,稳定性增强,颗粒聚合,大孔隙减少,小孔隙增多,孔隙逐渐均匀化。

Detailed laboratory tests and numerical studies of soft soil creep have been conducted on undisturbed soft soil in Tianjin Binhai New Area which considers both macro and micro aspects. The results show: the studied soft soil performs significant nonlinear creep behavior; the laboratory test results of both undisturbed and disturbed soft soil show that the structure has significant effects on the creep characteristics of soft soil; the essential reasons for the significant creep behavior are the loose piece-frame structure,the side-to-face contact type and the large void ratio. During the creep deformation,the soil particles have aggregated and the stability of soil structure has been enhanced. The evolution of pore structure follows the theory of homogeneity.