1D-consolidation analysis based on UH model considering time effect

Abstract

The soil stress-strain relationship under 1D consolidation condition was derived from the unified hardening( UH) model considering time effect. Based on this,a governing differential equation of 1D consolidation was established,which could simultaneously describe the deformation behavior of both primary and secondary consolidation. The one direction drainage consolidation problem was analyzed by the differential method. Since there is the phenomenon of relaxation that the effective stress pressure near the impermeable layer would decrease during the initiation of loading,a formula that can reflect the decrease of effective stress by time was deduced. Then,numerical analysis of the influence of secondary consolidation parameter,over consolidation ratio and the consolidation and swelling index was made and the results prove the conclusion of the formula. Besides,the laboratory tests were used to confirm the numerical prediction results of the governing equation. Depending on the condition that when the primary consolidation was almost finished,the main deformation was produced by secondary consolidation,a relationship between average degree of consolidation and time was deduced,which could be used to predict the time when primary consolidation would be finished.