Research On Hysteretic Performance And Design Method Of Angle-steel Concrete Columns

The open spandrel angle iron concrete column with no reinforcement what put angle iron on the corners of rectangular concrete columns (equivalent to the vertical steel reinforced in concrete column), and a horizontal steel plate (equivalent to stirrup in concrete column) will connect with angle iron to form steel frame, so that together with concrete to form one force, to improve the bearing capacity and ductility of the specimen. Angle reinforced concrete will greatly improve the ductility of concrete, it can give full play to the performance of two materials, the steel quantity close to the reinforced concrete structures, but more economical than SRC (steel reinforced concrete) and CFT (concrete filled steel tube) at the same time, angle steel frame can be prefabricated in the factory, simplify the construction process, shorten the construction period, the actual project will achieve good economic and social benefits.The building structure in the earthquake zone, in the case of being rare earthquake attacked, frame column, especially in the bottom, will inevitably through the course of cycle deformation, which repeatedly enter the non-flexible working range, resulting in structural damage, so the research of frame column hysteretic behavior was essential. Center around this problem, 4 aspects of investigation are carried out for ASCC:1) Based on the existing steel and the constitutive model with stirrup constraint, the constitutive models of angle-steel and concrete with angle-steel constraint are given.2) 9 ASCC specimens with shear steel plate (ρsv=1.18%~2.09%) are tested subjected to the horizontal low cyclic loading, in which, the shear span ratio is 3 and axial compression ratio is different. (n0=0.33~0.42). Using the material constitutive model proposed in the paper, simulation analysis of 9 ASCC skeleton curves is calculated by numerical simulation, and the calculated results agree well with the test results. This verifies the rationality of the material constitutive relation.3) Then the influence of factors on the performance of the ASCC is explored, such as the axial compression ratio, shear steel plate ratio, concrete compression strength, steel ratio, yield strength of steel and shear span ratio, etc. The hysteretic models for the load-displacement and the moment-curvature are established, and this provides reference for the elastic-plastic history analysis of structure.4) 4 aspects of design and construction suggestions on angle- steels concrete column are presented, they are general principles, types of structure, seismic structural measures, design of beams and columns and construction of joints.