摘要
PBL连接件由于其较高的承载力和刚度,良好的延性和抗疲劳性能,在组合结构中被广泛应用。为进一步研究约束强弱对叠合型PBL连接件受力性能的影响,考虑贯穿钢筋直径、开孔孔径以及约束状态3个影响因素,设计制作7组叠合型PBL连接件,进行推出试验,观察试件的破坏过程和破坏模式。基于国内外推出的试验结果,量化分析了横向钢筋约束、贯穿钢筋直径及开孔尺寸等因素对PBL连接件受剪承载力的影响,建立了抗剪承载力计算公式。结果表明:PBL连接件孔内混凝土榫发生双面剪切破坏,贯穿钢筋产生弯剪变形,且内部混凝土榫剪切面平滑度和孔中贯穿钢筋的弯剪变形程度受到横向钢筋约束强弱的影响。配有贯穿钢筋及横向钢筋试件的荷载-滑移曲线均出现了二次强化效应,横向钢筋的约束使连接件荷载-滑移曲线峰值后保持稳定的持荷能力,显著提高了连接件的承载能力。考虑了横向钢筋约束非线性影响和多孔耦合作用的PBL连接件承载力计算公式具有更好的精度,可适用于有、无贯穿钢筋的构件设计,物理意义明确,应用范围更加广泛。
With the development of hybrid structure bridges and composite structure,shear connectors have gradually become an essential part of the structure,among which Perfobond Leiste(PBL)connectors are widely used in practical engineering due to their high load carrying capacity and stiffness,good ductility and fatigue resistance.In order to further study the influence of constraint strength on the mechanical properties of superposed PBL connectors,the failure process and the mode of specimens were observed through the push-out test of seven groups of superposed PBL connectors,and the influence of the hole diameter,perforating rebar diameter and constraint state on the mechanical properties of specimens was studied.Based on the test results of specimens at home and abroad,the effect of the perforating rebar diameter,hole size and transverse reinforcement constraints was quantitatively analyzed and the calculation formula of shear bearing capacity of PBL connectors was proposed.The test and calculation results show that the shear failure of the concrete dowel and the bending-shear deformation of the perforating rebar are observed.The smoothness of the internal concrete dowel shear surface and the degree of bending-shear deformation of the perforating rebar are influenced by the transverse reinforcement constraint.The load-slip curves of the specimens with the perforating rebar and the transverse reinforcement have the secondary strengthening effect.The constraint of transverse reinforcement keeps the load stable after the peak load and obviously improves the bearing capacity of the connectors.The calculation formula of shear bearing capacity of PBL connectors considering the non-linear influence of transverse reinforcement restraint and multi-hole coupling effect has better accuracy and can be applied to the design of members with and without penetrating reinforcement,and also considers the influence of porous coupling action on the shear bearing capacity of PBL joints,with clear physical meaning and wider application scope.
作者
郭江然
史庆轩
马格
李腾飞
杨枫竹
GUO Jiangran;SHI Qingxuan;MA Ge;LI Tengfei;YANG Fengzhu(School of Civil Engineering,Xi’an University of Architecture&Technology,Xi’an 710055,China;Key Lab of Structural Engineering and Earthquake Resistance,Ministry of Education,(XAUAT),Xi’an 710055,China;China Qiyuan Engineering Corporation,Xi’an 710016,China)
出处
《地震工程与工程振动》
CSCD
北大核心
2023年第6期25-35,共11页
Earthquake Engineering and Engineering Dynamics
基金
国家自然科学基金项目(52178505,51878540)。
关键词
PBL连接件
推出试验
力学性能
约束状态
受剪承载力
PBL connectors
push-out test
mechanical properties
constraints
shear bearing capacity
