考虑次固结效应的流变固结理论研究

软土的固结与蠕变是土力学研究和工程建设中需要考虑的重点问题, 但是传统的固结理论, 例如太沙基固结理论没有考虑软土的流变特性, 对软土的次固结沉降无法做出准确的解释。为了研究软土的固结与蠕变以及次固结沉降特性, 掌握其应力和变形规律, 本文对传统的固结理论进行了改进。在太沙基一维固结理论的基础上, 利用次固结系数和修正的Singh-Mitchell经验蠕变模型, 建立了考虑次固结效应的一维流变固结微分方程。在太沙基三维固结理论和比奥固结理论的基础上, 利用修正的Singh-Mitchell经验蠕变模型, 建立了考虑次固结效应的三维流变固结微分方程。新建立的流变固结微分方程能够更加准确地反映软土固结和蠕变性状的应力-应变-时间关系, 为软土固结沉降研究提供新的理论依据。

RHEOLOGICAL CONSOLIDATION THEORY OF SOFT SOILS WITH SECONDARY CONSOLIDATION EFFECT

Creep and consolidation of soft soil are key issues in soil mechanics research and engineering construction. But the traditional consolidation theory cannot consider the rheological properties of soft soil. The secondary consolidation settlement of soft soil cannot be explained accurately. In order to research the consolidation and creep characteristics of soft soil, the secondary consolidation settlement and the rule of stress and deformation, this paper improves the traditional consolidation theory. On the basis of Terzaghi one-dimensional consolidation theory, one-dimensional rheological consolidation differential equation considering the effect of secondary consolidation is established. It uses the coefficient of secondary consolidation and modified Singh-Mitchell's experience creep model. On the basis of Terzaghi three-dimensional consolidation theory and Biot consolidation theory, three-dimensional rheological consolidation differential equation considering the effect of secondary consolidation is also established. It uses the modified Singh-Mitchell experience creep model. The new rheological consolidation differential equation can reflect the consolidation and creep character of soft soil and the stress-strain-time relationship more accurately. It can provide new theoretical basis for the study of the soft soil consolidation settlement.