液化砂与粘土地层中夯扩挤密碎石桩施工工艺探究  

Installation of Rammed Gravel Columns with Expanded Base in Alternating Cohesive and Liquefiable Sandy Soils

作　　者：黄连芬 黄均雄 HUANG Lianfen;HUANG Junxiong(Guangxi Geological and Mineral Construction Group Co.Ltd.,Nanning 530000;Guangxi Power Grid Co.,Ltd..Nanning Power Supply Bureau,Nanning 536100)

机构地区：[1]广西地矿建设集团有限公司,南宁530000 [2]广西电网有限责任公司南宁供电局,南宁536100

出　　处：《土工基础》2021年第3期257-259,267,共4页Soil Engineering and Foundation

摘　　要：以某城市副中心商务区泵站基础施工所在的液化土与粘土互层为工程背景,在分析其工程地质和水文地质概况的基础上,从施工准备工作、施工步骤和施工工艺流程对液化砂土层夯扩挤密碎石桩施工工艺进行了详细试验设计和分析。液化砂土与黏土层夯扩挤密施工步骤主要分为5个步骤,分批填料量应控制在0.3m3,首先采用大能量夯击挤密桩身材料,当离施工地面小于2.0m时,为防止地面隆起,采用小能量夯击。本文研究了这类型地层的夯扩挤密碎石桩施工质量控制和检验标准,确定了夯扩挤密碎石桩工艺在液化砂与粘土互层项目中的工艺性参数,验证了夯扩挤密碎石桩工艺对该类型地层处理施工的依据。This paper presents a ground improvement case study of a pump station project with the alternating of cohesive and liquefiable sandy soils near the Central Business District.Based on the engineering and hydrological geologic conditions,the effect of the installation preparation,installation sequence and method on the rammed gravel column with expanded base is evaluated in detail through various trial tests.The installing the gravel column can be divided into five steps.The quantity of the gravel backfill at each time should be controlled with 0.3 cubic meters.Larger ramming energy should be used to compact the gravel and the energy should be reduced when the depth is less than two meters from the ground surface in order to minimize the ground heave.The rammed gravel column installation quality control criteria,testing items and design parameters in the alternating of cohesive and liquefiable sandy soils are discussed in this paper.

关 键 词：砂土液化 夯扩挤密碎石桩 地基处理 

分 类 号：TU472[建筑科学—结构工程]