Three dimensional Consolidation Analysis of Sand Drain’s Ground Under Combined Vacuum and Surcharge Preloading Considering Loading Process

Abstract:

Based on the partial differential equations of both radial and vertical consolidation of sand drain’s ground under instantaneous loading condition,the real loading process is decomposed as a set of instantaneous loading problems by the developed program and threedimensional consolidation analysis is made of the sand drain’s ground under combined vacuum and surcharge preloading with a consideration of the real loading process.The calculation result of the project shows that the average consolidation rate of ground is generally slower than that under instantaneous loading condition due to the effect of loading time.The consolidation degree of ground is influenced by the loading time Ti under the single ramp loading or multiramp loading conditions.The longer loading time Ti is,the slower consolidation rate of ground is.Under single ramp loading,the inflexions of degree of consolidation curves appear at Ti points,the consolidation rate of which is maximum.

Key words:degree of consolidation; combined vacuum and surcharge preloading; loading process; sand drain’s ground