堆载预压法中回填层加固效果的检测分析

结合洋山四期工程实例,对回填层(砂土)分阶段检测的成果资料进行分析、比对,研究回填层在堆载预压作用下的物理力学性质变化规律。通过对不同预压荷载及不同时间点回填层的密实度、强度以及变形特性的检测,揭示其随荷载、时间的变化规律,为判别回填层需加固的范围、深度及确定回填层的地基加固工艺提供技术参考。分析结果表明:随着荷载的增加和堆载时间的增长,回填层的工程地质性质得到明显改善,且效果比利用自重固结的回填层更明显。

Test of reinforcement effect of backfill layer by surcharge preloading method

Based on Yangshan Phase IV project,we analyze and compare the test results of the backfill layer (sand soil),and study the physical and mechanical properties of backfill layers under preloading.According to the tests of the density,strength and deformation characteristics of the backfill layer of different preloads and periods,we reveal the variation rules of them with the load and time of the backfill layers to serve as technical reference for estimating the scope,depth and determining the foundation reinforcement technique of the backfill layer.The analysis results indicate that with the increase of the load and loading time,the engineering geological properties of the backfill layer are improved obviously,and the improvement effect is more obvious than that by the self-weight.