The Studies On Force Mechanism Of Steel Pipe Concrete Structural Wall Of Small Shear Span Ratio

Steel pipe concrete structural wall of small Shear span ratio is a new type of Steelconcrete structural wall. Through the combination of the steel tube,the concrete andreinforcing steel, They can play the full advantages of steel tube for itself and Effectivelyprevent the Shear failure of Low shear walls.At the same time,some performance have a greatimprovement such as ductility and the ability of energy dissipation, vertical bearing capacity.In order to research and improve the theory of Steel pipe concrete structural wall of smallShear span ratio,and promote the applied in practical engineering as soon as possible,Iresearch the seismic behavior and seismic behavior of the wall by some experiments andsome maturational theories. The main contents is shown below.(1)In this experiment，four specimens were constructed and tested under low cyclicreversed lateral loading. We studied the failure process and failure mechanism of thespecimens under the horizontal and vertical load. And analyzed the steel pipe quantity,horizontal distribution steel reinforcement ratio and other parameters on the bearing capacityof the shear wall specimen, hysteresis behavior, ductility, energy dissipation capacity and theinfluence of the damage characteristics. We also analyzed the flat section assumption on theapplicability of the new type of shear wall, the groundwork for the analysis of bearingcapacity.(2) In order to verify the reliability of the modeling methods and parameters we carriedout the nonlinear finite element simulation analysis of the specimens. Our paper show theaxial pressure ratio, number of steel pipe, steel pipe wall thickness, tube spacing, the ratio ofthe steel pipe diameter and wall thickness, horizontal distribution of steel reinforcement ratio,ratio of longitudinal reinforcement and depth of the dark column shear wall shear bearingcapacity and the ability of degeneration, in the end, to get the main parameters affecting theseismic performance of shear walls, the seismic design for reference.(3) On the basis of experimental studies of steel pipe concrete structural wall of smallShear span ratio, we put forward the new type of shear bearing capacity of shear wallcalculation model and the formula of ultimate bearing capacity, compared with the test results show that the formula is recommended value results agree well with the experimental values.(4)A new type restoring force model of steel pipe concrete structural wall of small Shearspan ratio was take out on the basis of the hysteretic curve and skeleton curve of experiments.Through experiment fitting and research method of combining the theory, established a newtype of reinforcement of small shear span ratio steel-concrete composite shear wall three lineskeleton curves, skeleton curves is also given the calculation formula of every key point. Fornew type of reinforcement of small shear span ratio of steel and concrete composite shear wallstiffness degradation rule and hysteresis rules are analyzed. The results indicate that steel tubeyield strain, axial compression ratio, ratio of longitudinal reinforcement and depth of darkcolumn, stirrup stirrup characteristic value on skeleton curves affected by the stiffness of thedecline.