逆作微型钢管桩复合地基承载变形特性及应用  

Load-bearing Deformation Characteristics and Application of Reversed Micro Steel-pipe Pile Composite Foundation

作　　者：魏应乐[1] 马海龙[2] WEI Yingle;MA Hailong(School of Architecture Engineering,Anhui Water Conservancy Technical College,Hefei 230061,China;School of Architecture Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]安徽水利水电职业技术学院建筑工程学院,安徽合肥230061 [2]浙江理工大学建筑工程学院,浙江杭州310018

出　　处：《安徽建筑大学学报》2023年第2期14-18,32,共6页Journal of Anhui Jianzhu University

基　　金：安徽省自然科学基金项目(2022AH040303)。

摘　　要：采用粉喷桩加固的某软土地层上的6层住宅楼,由于沉降较大,出现较多裂缝而拆除重建,根据现场具体施工条件,决定采用逆作微型钢管桩对既有地基进行加固。为了分析钢管桩复合地基与粉喷桩复合地基的加固特性异同,地基土采用摩尔-库伦模型,桩采用弹性模型,计算两种复合地基。计算结果表明,粉喷桩复合地基压缩主要发生在加固区域的上部,粉喷桩不能有效将荷载传递到桩端,粉喷桩复合地基承载变形特性接近于天然地基。微型钢管桩复合地基压缩区域可达桩端下一倍桩长以下,钢管桩能有效将荷载传递到桩端,微型钢管桩复合地基承载变形特性接近桩基础。采用逆作微型钢管桩加固地基,解决了噪音、挤土问题,并保证了施工安全,经逆作钢管桩加固的住宅楼沉降很小。A 6-story residential building on the soft soil layer reinforced with powder-jetting piles needs to be demolished and reconstructed due to a large number of cracks causing by large settlements.According to the on-site condition,the reversed micro steel-pipe pile are used to reinforce the existing foundation.In order to analyze the similarities and differences of the reinforcement characteristics between the steel-pipe pile composite foundation and the powder-jetting pile composite foundation,the Mohr-Coulomb model is adopted for the foundation soil and the elastic model for the pile to calculate these two composite foundations.The calculation result shows that the compression of the powder-jetting pile composite foundation mainly occurs in the upper reinforcement zone;the powder-jetting pile can not effectively transfer the load to the pile tip;the bearing deformation characteristic of powder-jetting pile composite foundation is close to natural foundation.While the compression of the micro steel-pipe pile composite foundation can reach more than one pile length below the pile tip,the steel-pipe pile can effectively transfer the load to the pile tip and the bearing deformation characteristic of powder-jetting pile composite foundation is close to pile foundation.Using the reversed micro steel-pipe piles to reinforce the foundation solves the problem of noise and soil compaction,and ensures the safety of the construction.The settlement of the residential building reinforced by the reversed steel-pipe pile is small.

关 键 词：微型桩 地基加固 荷载传递 压缩量 逆作法 

分 类 号：TU473.1[建筑科学—结构工程]