Study On Seismic Behavior Of HSRC Frame Column

Steel high-strength reinforced concrete(HSRC) structures which mainly consist ofshaped steels and high-strength concrete meet the contemporary need of span, heightand capacity. This paper based on experimental research and theoretical analysis andfinite element analysis, studied the seismic performance of HSRC columns under lowcyclic reversed loading. A restoring force model had been established and the influenceof flanges with studs had been studied. The scientific project of Chongqing constructioncommission was considered in this paper, and the follows are the research results:①For obtaining the parameters of HSRC columns, a cyclic loading experimentcontaining19test specimens(strength grade covered69.9-86.6MPa) were conducted.Such parameters include failure modes, hysteretic curve, skeleton curve, ductility ratioand capability of energy dissipation. Based on the experiment, the influence of differentfactors-such as steel content, axial compression ratio, stirrup ratio, shear span ratio andconcrete strength-were investigated.②A restoring force model for HSRC columns had been established by fitting thetest data of the cyclic loading experiment.③The finite element analysis(FEA) of the columns under cyclic loading matchedwith the test results. A parameter analysis was conducted with this FEA model.④A simplified calculation formula for bond-failure strength of HSRC wasderived by the test results. Calculation method of bending strength was studied, thesafety of this method was compared with the method in relative code[8]. The sensitivityof parameters towards ductility coefficient was shown in this paper. A simplifiedcalculation formula for compression and bending and shearing of HSRC members wasobtained.⑤A contrast test containing5specimens for the influence of flanges with studswas conducted under cyclic loading. The result came to a conclusion that flanges withstuds obviously increased the hysteretic curve, skeleton curve, ductility ratio andcapability of energy dissipation of HSRC columns.⑥The optimum form of studs was obtained by a contrast test of6differentarrangement forms of studs. The test results illustrated that a HSRC column with lowsteel content and optimum studs arrangement showed a seismic performance as good asHSRC columns with steel content at normal level. This means that studs in flanges could save steel in structures.