弯折贯穿钢筋PBL剪力键力学性能试验

Experimental on Mechanical Properties of PBL Shear Connector with Bent Passing Rebar

本文针对传统PBL剪力键进行改良,提出了一种新型弯折贯穿钢筋PBL剪力键,并对2个普通PBL剪力键试件和6个弯折贯穿钢筋PBL剪力键试件进行了推出试验。试验中,采用百分表测量了钢–混结合面的相对滑移量,采用光栅应变传感器实时监测贯穿钢筋在加载全过程中的应变值,详尽研究了两种不同形态贯穿钢筋PBL剪力键的破坏形态、抗剪承载力及荷载–滑移规律。运用ABAQUS软件对2种贯穿钢筋PBL剪力键进行数值分析,对比分析了试验和有限元计算结果,调整相关参数,得到一种准确的数值模拟方法。研究结果表明,弯折钢筋PBL剪力键的抗剪承载力较普通PBL剪力键提高了10.42%,抗剪刚度提高了10.67%,其抗剪性能优于传统PBL剪力键。弯折贯穿钢筋能有效提高PBL剪力键的延性,改善了剪力连接件在达到承载力时混凝土出现贯通裂缝的现象,延长了结构的使用寿命。

In this paper,the traditional PBL shear connector is improved,and a new type of PBL shear connector with bent passing rebar is proposed.Two ordinary PBL shear connector specimens and six PBL shear connectors with bent passing rebar specimens are pushed out.In the test,the relative slip of the steel-concrete interface was measured by dial gauge,and the strain value of the passing rebar was monitored by the fiber Bragg grating strain sensor in the whole loading process.The failure modes,shear capacity and load-slip laws of two kinds of PBL shear connectors with different passing rebar are investigated in detail.The ABAQUS software is used to perform numerical analysis on the two through rebar PBL shear connectors.The experimental and finite element calculation results are compared and analyzed,and the relevant parameters are adjusted to obtain an accurate numerical simulation method.The results show that the shear capacity and stiffness of PBL shear connector with bent passing rebar are increased by 10.42%and 10.67%respectively.The shear performance of the PBL shear connector with bent passing rebar is better than the traditional PBL shear connector.Bent passing rebar can effectively improve the ductility of the PBL shear connector,improve the phenomenon of concrete through cracks when the shear connectors reach the bearing capacity,and prolong the service life of the structure.