Experimental Study On Seismic Performance Of RC Short Column With Welded Stirrups

Reinforced concrete structure is regarded as a kind of traditional structure type, itsapplication is already very extensive,to restrict concrete deformation, the stirrupregularly makes use of double leg band with hook or compound hoop, the traditionalcomposite stirrups are processed in the construction field, many procedures and timeconsuming; at the same time, if there is requirement for seismic resistance,the hookstraight length has to meet the provisions of the10d, and because of reinforcedoverlaps, both certainly will cause unnecessary reinforced waste;under the condition ofthe volume distribution band large rate, the more hooks also will give concreteconstruction vibro a lot of trouble, etc., but welding composite stirrup has solved to alarge extent many faults that the above traditional composite stirrups bring, we can notonly realize the industrialized production of welding composite stirrups,but also can bea big advantage to save reinforcement amount and speed up the construction speed.This paper mainly undertakes the study on seismic force performance of RC shortcolumn with welded compound stirrup,with emphasis on the following several aspects:(1) the pull-out test research respectively on four concrete test cubes that containresistance spot welding solder joints and two concrete test cubes with traditional hookanchoraged in so as to research mechanical properties of the solder joint,with thetraditional hook mechanical properties compared;(2) the five RC short columns withfull resistance spot welding of composite stirrups constraint and three traditionalcomposite stirrups constraint reinforced concrete short columns for cyclic quasi-staticloading test and seismic stress performance contrast.Through the pull-out test,we can conclude that the welded steel joint strength can meet the requirements of the anchoring force.And it give comprehensive analysis on themost important aspects of seismic performance for the eight RC short columns,such asfailure pattern, hysteresis curves, skeleton curves, displacement ductility and energydissipation, stiffness degradation and intensity attenuation effects and mainly study theinfluence law of seismic performance on RC short columns with welded compoundstirrup,such as the shear span ratio, stirrup ratio and axial pressure ratio, the resultsshow that with the increase of shear span ratio, stirrup ratio and axial compression ratiodecreases,the energy dissipation capacity and ductility of RC short columns with weldedcompound stirrup are improved;the seismic performance of RC short columns withwelded compound stirrup is basically consistent with traditional composite stirrupsconstraint reinforced concrete short columns,but the shear capacity is significantlyhigher than the ordinary short column.On the basis of the experimental study and MCFT theory,the paper puts forwardshear bearing capacity calculation formula of RC short column with welded compoundstirrup,with considering the shear zone and the longitudinal reinforcement dowel pin onthe shear contribution;the theoretical calculation results are in good agreement with thetest resultsthe test results.Then it analyses the influence of axial compression ratio,stirrup ratio and shear span ratio on the shear bearing capacity,using the test data,thispaper fits out the calculation formula of shear bearing capacity for reinforced concreteshort column with welded stirrups, the calculation values coincide with the test results,it can be used for engineering design.