无预应力钢绞线笼灌注桩设计与施工技术研究

Study on Design and Construction Techniques for Non-prestressed Steel Strand Cage Cast-in-place Pile

传统灌注桩的钢筋笼一般分为多节,通过多次焊接将上下节连接,难免影响施工质量和施工效率。结合某改扩建具体项目,提出一种钢绞线笼灌注桩,选取无预应力钢绞线作为主筋,采用螺旋箍筋及加劲筋提高整体刚度,并给出了钢绞线笼灌注桩的设计方案及设计方法,通过有限元模拟对比分析了普通钢筋笼灌注桩与钢绞线笼灌注桩在轴拉与轴压下的受力及变形机理。基于优化设计结果,进行了现场工艺试验,形成了灌注桩超长钢绞线笼同步制作下放工艺,可为以后类似工程提供借鉴。

The reinforcement cages of traditional cast-in-place piles are typically divided into multiple sections and connected through repeated welding,which can compromise construction quality and efficiency.This research proposes a steel strand cage cast-in-place pile,selecting non-prestressed steel strands as the main reinforcement.Spiral stirrups and stiffeners are used to enhance overall stiffness.The design scheme and methodology for the steel strand cage cast-in-place pile are presented.Finite element simulation is employed to compare and analyze the stress and deformation mechanisms under axial tension and compression between ordinary steel cage cast-in-place piles and steel strand cage cast-in-place piles.Based on the optimized design results,a field process test was conducted,leading to the development of a process for the simultaneous fabrication and lowering of super-long steel strand cages for cast-in-place piles.This technique provides a valuable reference for similar future projects.