The Research On The Mechanical Behavior Of Steel Reinforced Concrete Frame

Steel reinforced concrete frame structure (SRC) is a structure with high bearing capacityand better elastoplatic, which is consisted of steel reinforced concrete columns or beams. Ithas broad prospects for development in seismic applications, therefore researching for itsmechanical behavior has an important theoretical significance and is valuable in engineeringapplications. However, now researches on the entity SRC structure are much less in ourcountry.This paper built finite element models of SRC structure with solid elements by ANSYS,which is general finite element analysis software, and the finite element analysis were basedon the horizontal direction monotonic and cyclic loading of the structure. Through the finiteelement analysis, it found that SRC structure had high bearing capacity and better elastoplatic,and the hysteretic curve of structure in the cycle load was a spindle shape, which moaned theenergy dissipation of structure were better. According to the structure stress and concretecracking analyses, the structural response under laterally loaded during the complete loadinghistory could be divided into three stages, elastic stage, elastic-plastic stage and the plasticdamage stage. For section steel in the sided column, its maxim press appeared at the top andbottom sections of columns, but smaller at other parts, during the complete loading history. Asfor section steel in the middle column, its stress distribution was basically same as whichperformed in the sided column, nothing but its press was also larger at beam-column joints.During the complete loading history, stress distribution of concrete in the columns were justas the same, larger at the top section, the bottomed section and the beam-column joints,smaller at the other parts. Then designs for beam-column joints should been stronger so that itcan meets the demand, strong joint, of seismic designed. By changed axial compression ratio,strength grade of section steel and concrete, this paper built three groups, totally eleven, analysis modes, then found their affects to mechanical behavior of SRC structure based on thefinite element calculation results. Bearing capacity of the SRC structure declined about18%as axial compression ratio (c) increased per0.1. But on the one hand as <0.4, it couldnot be fully reflected, on the other hand as>0.6, the hysteretic curve of SRC structure hadsignificant pinch phenomenon, and it moaned structure plastic were bad. Then axialcompression ratio should mainly taken0.4-0.6, and not larger than0.6in structure design.Bearing capacity of SRC structure would be greatly increased when strength grade of sectionsteel changed, low to high, but hysteretic and plastic behavior of the structure got worse.Therefore engineers should comprehensively considerate economic applicability, and thenchose the best strength grade of section steel. Bearing capacity of SRC structure would beincreased when strength grade of concrete changed, low to high, but its limit displacementfirst increased and then declined, as C40the max. And the hysteretic and plastic behaviors ofhigh strength grade of SRC were much better. Then choosing strength grade of concrete needcomprehensively considerate economic applicability and safety, and it should not lower thanC35.This paper deeply analyzed the mechanical behavior of SRC structure under horizontalcyclic loading and got some results, which were valuable for theory research of SRCmechanical behavior.