MODEL EXPERIMENTS ON SEEPAGE FAILURE OF DEEP FOUNDATION PIT CONSIDERING INFLUENCE OF FOUNDATION PILES IN SANDY SOIL
考虑基桩影响的粉砂地基深基坑流砂模型试验研究

Using home-made seepage and seepage failure test apparatus,model experiments in different conditions were carried out.Based on the analysis of water head and soil deformation results,the seepage failure problem of deep foundation pit in uniform sandy and silty soil is investigated.The results demonstrate the seepage failure modes in deep foundation pit in uniform sandy and silty soil.Combined with numerical simulation and model experimentst,he mechanism of seepage failure is analyzed based on the change of soil stress.Moreover,the effect of foundation pile on seepage failure and the effect of seepage on the deformation and stress of foundation pile are studied.According to the research,the plastic strains firstly appear on the foot of the supporting structure.Seepage failure takes place when the plastic zone joints together;and the failure model is wedge type in uniform soil.Influenced by cohesiont,he water head difference in silt is more than that in sand when seepage failure takes place.Influenced by piles,the water head difference of seepage failure also increases.