Experimental Study On Seismic Performance Of M-shaped Steel Composite Wall

Shear wall,as one of the important lateral resisting elements of buildings,can prevent building structures from collapsing due to excessive deformation during an earthquake.Under the background of building industrialization in China,the research on shear wall mainly focuses on the integration of Fabricated structure and insulation structure.This paper produces the M-shaped steel composite wall.The M-shaped steel acts as the vertically distributed reinforcement of the shear wall.Non-demoulding formwork such polystyrene,metal lathing and cement-fiber board is fixed on either side of the M-shaped steel to achieve an integrated property of structure and insulation.The structure of MSSCW is different from traditional shear walls,which can effectively avoid brittle shear failure of low-shear walls and improve seismic performance,and there are relatively few studies on such shear walls.Therefore,this paper conducts experimental study on its seismic performance and failure mode to lay the test basis and data support for its engineering application.This paper conducts pseudo-static test and theoretical analysis.The main contents include:(1)Pseudo-static tests of six groups of M-shaped steel composite wall have been completed.The effects of the type of non-demoulding formwork,axial compression ratio and horizontal reinforcement ratio on the seismic performance of the wall have been studied.The test results show that MSSCW had two stages of the failure.The stress of the wall was transferred from the whole to the cracked wall with the increase of deformation.When reducing the horizontal reinforcement ratio,the bearing capacity of the wall reduced significantly,the stiffness degeneration delayed and the overall ductility and energy consumption of the wall improved.And,the type of non-demoulding formwork had a certain impact on energy consumption capacity but no impact on the bearing capacity of the wall.The results also show that the appropriate axial compression ratio can improve the bearing capacity but will reduce the ductility of the wall.(2)Based on the related codes and research result at home and abroad,the formulas suitable for the shear capacity of the M-shaped steel composite wall have been studied.Comparing the calculation results with the test results,the calculation results of Chinese codes,Zelanian codes and American codes were relatively close to the test values and were available for the engineering design requirements of M-shaped steel composite walls.(3)Based on the existing restoring force model and pseudo-static test results of the M-shaped steel composite wall,this paper establishes the calculation formula of 3-line skeleton curve of the wall and stiffness degradation formula and proposes the 6-line hysteresis rule.wall.