(1 广州市设计院集团有限公司, 广州 510620; 2 广州建筑股份有限公司, 广州 510030;3 广州市建筑集团有限公司, 广州 510030; 4 华南理工大学土木与交通学院, 广州 510640)

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。

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

中图分类号:TU472. 3 文献标志码:A 文章编号:1002-848X(2022)24-0100-06

DOI:10. 19701 / j. jzjg. ZJ220059

Study on key technologies of rigid pile composite foundation incorporated with adjustable positive-negative air pressure

HUANG Junguang1,2,3, ZHANG Heng1,2,3,4, LI Weike1,2,3, LI Lei1,2,3

(1 Guangzhou Design Institute Group Co. , Ltd. , Guangzhou 510620, China; 2 Guangzhou Municipal ConstructionCo. , Ltd. , Guangzhou 510030, China; 3 Guangzhou Construction Group Co. , Ltd. , Guangzhou 510030, China;4 School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510640, China)

Abstract: Although the method of injecting gas pressurization can improve the effect of vacuum drainage consolidation ofsoft soil foundation, it also induces some problems such as the long consolidation period, insufficient consolidation extentand blockage of drainage channel. Aim at above problems, on the basis of analyzing the defects of existing pressurizedvacuum drainage consolidation technology, the rigid pile composite foundation incorporated with adjustable positive-negativeair 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 wereestablished by analyzing the pore water migration law. In addition, according to the difference of strata, the measures ofhole opening and sealing technology of pile body suitable for multiple sites were developed. The practice results of actualprojects show that the rigid pile composite foundation incorporated with adjustable positive-negative air pressure can fullyutilize both the advantages of high bearing capacity of prefabricate pile and rapid drainage of vacuum preloading, canovercome a series of shortcomings of vacuum preloading technology, which realizes rapid and efficient consolidated of softsoil foundation. Research results and ideas can provide technical guidance and reference for soft soil foundation treatment incoastal area.

Keywords:positive-negative air pressure; rigid pile composite foundation; increase pattern of air pressure; anti-siltingtechnology; drainage consolidation

∗广州市建筑集团有限公司科技计划资助项目(2021-KJ006、2022-KJ017)。

第一作者:黄俊光,硕士,教授级高级工程师,注册土木工程师(岩土),主要从事岩土工程设计工作,Email: hj020@ 126. com。

[引用本文] 黄俊光,张恒,李伟科,等. 可调控正负压刚性桩复合地基关键技术研究[ J]. 建筑结构,2022,52(24):100-105. HUANG Junguang,ZHANG Heng,LI Weike, et al. Study on key technologies of rigid pile compositefoundation incorporated with adjustable positive-negative air pressure[J]. Building Structure,2022,52(24):100-105.