新近吹填淤泥地基浅表层加固现场对比试验

Field Comparison Test of Surface-layer Reinforcement of Newly Dredged Sludge Foundation

浅表层加固技术具有缩短工期、降低造价的优点。但同时工程实践中也发现一些问题:加固后土体均匀性差;加固后形成的硬壳层厚度和强度有限;滤管环向刚度差经常被压扁,影响真空度的传递效率。为解决上述问题,试验中在常规真空预压浅表层处理工艺方案的基础上,通过加密滤管,改原来的双排单管方案为单排单管方案,并且用自制的PVC滤管来代替常规法中的软式滤管。试验证明自制的PVC滤管和通过改进后的单排单管方案的加固效果优于常规方案,建议在浅表层加固过程中采用自制的PVC滤管和单排单管的施工方案。

In order to solve the problem that traditional vacuum preloading technology cannot use directly on newly dredged sludge,a new technology called surface-layer reinforcement technology is based on the mechanism of vacuum preloading.This method can shorten construction period,and reduce cost.But in the project practice also some problems are found.For example,soil uniformity is poor after reinforcement.The thickness and strength of the crust layer formated after reinforcement is limited.The soft filter tube is too soft to bear vacuum pressure,as a result,some of them often are crushed.These crushed tube affect the transfer of vacuum degree seriously.In this test we change the double-row to single-tube scheme which is often be used in conventional reinforcement to the single-row to single-tube scheme.At the same time,we use the self-made PVC filter tube to replace the soft filter tube.The field test proves that the reinforcement effects of single-row to single-tube and self-made PVC filter tube scheme are significantly better than of conventional reinforcement scheme.So we propose that we can choose the single-row to single-tube and self-made PVC filter tube scheme in the later surface-layer reinforcement.