摘要
虽然利用注气增压能够提高软土地基真空排水固结效果,但也存在着固结周期长、固结范围有限、排水通道淤堵等不足。针对上述问题,在分析现有增压式真空排水固结技术缺陷的基础上,提出了以透水混凝土管桩为增压/真空排水通道的正负压刚性桩复合地基技术,通过分析孔隙水的迁移规律,构建了新型正负压施加模式及防淤堵的滤膜孔径选择标准;并针对地层差异开发了适应多场地的桩身开孔措施及密封技术。工程实践结果证明,正负压刚性桩复合地基技术能够充分利用预制桩高承载力和增压式真空排水迅速的优势,克服现阶段真空排水固结技术的一系列缺陷,实现软土地基的快速高效加固。研究成果及思路可以为沿海地区软土地基处理提供技术指导和借鉴。
Although the method of injecting gas pressurization can improve the effect of vacuum drainage consolidation of soft soil foundation, it also induces some problems such as the long consolidation period, insufficient consolidation extent and blockage of drainage channel. Aim at above problems, on the basis of analyzing the defects of existing pressurized vacuum drainage consolidation technology, the rigid pile composite foundation incorporated with adjustable positive-negative air pressure was proposed, in which the perforated concrete pile was used as the air-boosted or vacuum drainage channel, and the applying pattern of positive-negative air pressure and the selection criteria of anti-siltation filter diameter were established by analyzing the pore water migration law. In addition, according to the difference of strata, the measures of hole opening and sealing technology of pile body suitable for multiple sites were developed. The practice results of actual projects show that the rigid pile composite foundation incorporated with adjustable positive-negative air pressure can fully utilize both the advantages of high bearing capacity of prefabricate pile and rapid drainage of vacuum preloading, can overcome a series of shortcomings of vacuum preloading technology, which realizes rapid and efficient consolidated of soft soil foundation. Research results and ideas can provide technical guidance and reference for soft soil foundation treatment in coastal area.
作者
黄俊光
张恒
李伟科
李磊
HUANG Junguang;ZHANG Heng;LI Weike;LI Lei(Guangzhou Design Institute Group Co.,Ltd.,Guangzhou 510620,China;Guangzhou Municipal Construction Co.,Ltd.,Guangzhou 510030,China;Guangzhou Construction Group Co.,Ltd.,Guangzhou 510030,China;School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,China)
出处
《建筑结构》
CSCD
北大核心
2022年第24期100-105,共6页
Building Structure
基金
广州市建筑集团有限公司科技计划资助项目(2021-KJ006、2022-KJ017)。
关键词
正负压
刚性桩复合地基
增压模式
防淤堵技术
排水固结
positive-negative air pressure
rigid pile composite foundation
increase pattern of air pressure
anti-silting technology
drainage consolidation
