PBL Shear In Steel-Concrete Composite Beams Under Strong Decay Study On Mechanical Properties Of Force Connectors

In recent years,steel-concrete composite beam bridge has been widely used in engineering because of its light weight,fast construction and excellent mechanical performance.With the continuous development of China’s economy,the increase of traffic volume and the use of chemicals,the probability of traffic accidents on hazardous chemicals transport vehicles is greatly increased.Once a traffic accident occurs,hazardous chemicals will damage the bridge.In order to deal with the follow-up treatment of traffic accidents in time and effectively,this paper studies the mechanical properties of steel-concrete composite beam bridge after strong corrosion.At home and abroad,the research on steel-concrete composite beams mainly focuses on the corrosion of stud shear connectors,but little on the corrosion of PBL shear connectors,so this paper mainly studies the mechanical characteristics of PBL shear connectors after strong corrosion.This paper combines experiment,numerical analysis and theoretical analysis,and mainly includes the following research contents:(1)Nine groups of 27 steel bars were corroded with 36% industrial hydrochloric acid for0 h,0.5 h,1 h,2h,4 h,8 h,12 h,24 h,48 h and 72 h,and then tensile tests were carried out on the corroded steel bars,and the degradation laws of mechanical properties of steel bars under different corrosion times and the triaxial constitutive model of steel bars under strong corrosion were obtained.(2)The penetrated steel bars with different corrosion times were poured into the steel-hybrid structure,and the failure form,shear bearing capacity,load slip curve and shear stiffness change values of PBL shear joints under different corrosion times were obtained,and strain gauges were posted at important stress positions of the specimens to study the internal stress characteristics of the shear connectors.(3)The finite element model was established by Abaqus,and the finite model was verified by comparison with the experiment,and the effects of concrete parameters,through-steel diameter,end pressure bearing mode and perforated plate aperture size on the shear bearing capacity of the shear connector under different corrosion times were established.(4)Based on the test data of other scholars and the results of this test,the shear bearing capacity formula of PBL shear connector with strong corrosion action was proposed on the basis of the existing formula of shear bearing capacity,and the shear stiffness and load-slip model of PBL shear connector under strong corrosion was obtained.