填土厚度大幅变化地质条件下强夯法应用研究

Application of Dynamic Consolidation Under the Geological Conditions of Big and Various Filling Heights

四川北川新县城体育中心为援助重建项目,工程所在地周边空旷无建筑物,地质条件复杂,土层为鱼塘和河道基础,以及拆除后尚未外运的建筑垃圾.原地貌高差较大,场区内均需回填,回填深度为2～9 m.根据工程实际条件,调整原来大开挖至持力层再分层回填的设计方案,改为利用当地河床多见的连砂石和粉土及破碎后的建筑垃圾混合料回填后强夯,以满足设计承载力的施工方案.强夯地基加固法缩短了工期,降低了工程造价,取得了良好的社会和经济效益.

The Beichuan New County Sports Center in Sichuan Province is an aid reconstruction project.There is no building around the project site.But the geological conditions are more complex.The soil layer is the fish pond,river base and construction waste which has not been shipped out after demolition.The altitude difference of the original landform is large,so the whole field region needs backfill and the depths of the backfill are from two to nine meters.In order to accomplish the construction scheme design,the original design scheme of the heavy excavation to bearing stratum and then layered backfill is adjusted to using dynamic compaction after the mixture of the local river sand,silt and crushed construction waste material is backfilled according to the actual conditions.The results of the tests show that the dynamic compaction shortens the construction period,reduces the project cost and achieves good social and economic benefits.