基于固结理论和蠕变模型的软土固结蠕变理论

通过分级加荷的方式对天津滨海新区经过真空预压处理后的软土进行一维压缩蠕变试验.根据试验所得到的成果,在Terzaghi一维固结理论的基础上,用修正的Singh-Mitchell经验蠕变模型建立了一个新的一维固结微分方程.该方程以一维压缩蠕变试验中所获得的土体力学指标作为计算参数,考虑了软土在主固结阶段结束后所产生的蠕变变形.利用该方程对不同深度和不同应力水平下的试样进行固结和蠕变计算,计算结果与试验结果很接近,表明该方程能够充分反映软土的应力、应变和时间的关系,适用于天津滨海新区的吹填软土地基.

Consolidation and Creep Theory Based on Terzaghi Consolidation Theory and Empirical Creep Model

Based on the one-dimensional compression creeping and step-loading test on the soft soil subjected to the vacuum preloading treatment in Tianjin Binhai New Area， the modified Singh-Mitchell empirical creep model was used to improve the Terzaghi consolidation theory， and a new one-dimensional consolidation equation was obtained. The new equation used the soft soil mechanics indexes， obtained from the one-dimensional compression and creep tests， as the calculation parameters， and considered the creep deformation generated after primary consolidation. The results obtained from the new equation on different depths of specimens with different stress levels are very close to the test results， which indicates that the new equation can reflect the stress-strain-time relationship of soft soil and is applicable for the soft soil foundation in Tianjin Binhai New Area.