The Influence Of ALC Infill Wall On Seismic Behavior Of Steel Frame Structure

With The development of steel structure has been nearly a hundred years of history.Many achievements have made in the research and technology of steel structure.But there are many problems about the role of infill wall in frame at home and abroad,and remain to be solved in these aspects.Both China's steel design code and seismic code have not taken into account the content of this area.Existing problems are the effect of infill walls' layout method and hole in the wall on the frame.Therefore,it is necessary to conduct in-depth research in these two aspects.ALC board has superior performance.It is a kind of lightweighted new material with good physical properties and strong fire-retardant properties.It can improve the structure of lateral resistance performance of steel frame,but also can reduce the weight of the steel frame.In this paper,finite element software ABAQUS is used to study the infilled steel frame system.Detailed research content and results are as follows:(1)Ten two floors and single-span models had been established.Monotonic loading and cyclic loading of low-cycle static testing on these models were carried out.Extract a series of models of monotonic loading-displacement curve,hysteresis curves,skeleton curve,the stiffness degradation curve,ductility parameters,energy dissipation ability and destroy the form analysis of these factors on the seismic performance.By comparison,it shows that use finite elment software to analysis the effect of infill wall in frame is feasible.(2)Compared with the pure steel frame,the infill wall steel frame structure can improve the bearing capacity,lateral stiffness and energy dissipation capacity of the structure under horizontal monotonic loading and low cyclic loading,but the ductility performance obviously degrades.When the wall is not cut,the damage of the wallboard mainly concentrates on the embedded parts.When the wall is cut,the damage of the wallboard mainly concentrates on the area of the wall that is not weakened.The bearing capacity of horizontal wallboard structure is lower than the vertical structure,but its energy dissipation mechanism is better than the vertical structure.(3)The hole has great effect on the bearing capacity,displacement,stiffness,ductility,energy dissipation ability and destroy the form.The ultimate bearing capacity,stiffness and energy dissipation capacity of the structure decrease with the increasement of the hole area,but the ductility performance is significantly improved.When the hole ratio exceeds 50%,the structure will has short-column-effect,and the wall will not take part in the energy consumption.Therefore,in the structural design should not be set too large window area.After opening holes,the bearing capacity of horizontal wallboard structure is approximately equal to that of vertical structure,but its energy dissipation mechanism is still better than vertical structure.(4)Based on the previous research results,a simplified calculation model which is suitable for this structural system is proposed.According to the equivalent-diagonal-strut model,the calculation formula of bearing capacity of the frame with infill walls is deduced theoretically.