打入预制桩消除地基液化试验研究

Experiment Research of Elimating Foundation Liquefaction by Driven Pre-formed Pile

真空和堆载联合预压法加固软弱地基具有固结时间短、土体侧向变形小、地基不会发生剪切破坏、加固地基土的承载力高等诸多优点。但作为真空堆载联合预压的外荷载（4~5m厚堆砂）,由于一般未进行预处理,处于松散~稍密状态,水下部分液化,对于采用桩基的重要建筑设计要求首先采用预处理方法消除液化,表层液化松散砂如何处理影响工期和造价,该文通过某工程打入桩挤密（振密）进行消除饱和砂土液化试验并和强夯加固吹填砂进行对比分析,提出了直接利用打入桩挤密（振密）作用加固吹填松砂不需另外预处理的方法,对类似工程具有借鉴参考意义。

United preloading method of vacuum and surcharge has the advantages of short time consolidation,small lateral deformation of soil,cann＇t occur the foundation shear failure,the high bearing capacity of foundaion soil consolidation to consolidate the soft foundation. But as the external loading（ 4 ~ 5m stack sand） of preloading method of vacuum and surcharge,because it isn＇t pretreated,so it presents friable ~little dense state,part of it presents liquefaction underwater. The important building design adopting the pile foundation requires that first it need adopt pretreatment to elimate the liquefaction. How to handle the liquid loose sand in surface will impact the engineering data and cost. This paper through driven pile compaction（ vibration） in an engineering to make the elimating saturation sandy soil liquefaction experiment,and it is compared and analysed with the consolidating dredger fill sand by dynamic compaction. And this paper puts forward that using the compaction（ vibration） to consolidate the dredger fill loose sand,and it needn＇t pretreatment,it has the reference significance for similar engineerings.