Study On The Mechanical Behaviors Of Prefabricated Structure Of Steel Frame With EPS Concrete Wallboard

With the proposal and development of the prefabricated residential building system,the researches on the material properties of the new wallboards and the mechanical behaviors of the structural systems have attracted a lot of attention of researchers in the construction field.Generally speaking,the steel frame structure with wallboard belongs to a composite wall structural system,which has the merit of fast construction.The wallboard,whose lateral stiffness is high,can resist the horizontal load combined with the steel frame,which makes this structure system a good lateral resisting system.Some researchers have maken large amount of experimental and theoretical researches in steel frame structure with specific wall or slab.And some of their results can be used in practice engineering programs.Under the guidance of national policy and the support of funds,we put forward a new kind of wallboard called EPS concrete wallboard assembled with prefabricated steel frame which is environmentally friendly,energy-saving and the whole system has good sound insulation and heat insulation performance.In order to apply this structural system to civil engineering field,we need further study about its mechanical behavior.This paper comprehensively studied the horizontal bearing capacity of column top,lateral stiffness and the progress of cooperative bearing of this combination wall-steel frame structural system through specific experimental test and finite element simulation.Then we put forward this system’s precise equivalent model and its applicable equation for calculating lateral stiffness.The results we got in this paper could help support the promotion of this kind of prefabricated steel frame structure with wallboard,which has definite value to engineering application.Contents and relative results of this paper are as follows:(1)Full scale tests of single steel frame and one steel frame with wallboard were operated.Before the test,material experiment was carried out and the loading plan was settled.Then in the test,horizontal statistic load was put on at the top of the column for steel frame and steel frame with wallboard respectively.Destruction process of the structure was recorded to compare the effect of wallboard to the bearing capacity and lateral stiffness of the steel frame.(2)Modeling and loading analysis simulation were carried out in ANSYS.And the mechanical characteristics of wallboard combined with the steel frame could be analyzed by ANSYS.In order to simplify the modeling process,a number of assumptions were considered and some errors in the experiment were ignored,which made the theoretical bearing capacity higher than that of the practical test.Comparing the results of ANSYS and the test records,the overall loading process and the destruction process were basically coincidence,which showed the validation of finite element simulation of ANSYS.(3)Based on relative theory,equivalent simulation model could be set to apply for this combination wall structure system.Considering the mechanical characteristics of wallboard,some theoretically hypothesis could be used to equate the combination wall structure system with diagonal strut model,and the calculation formula of the radius of the inclined bar was derived according to the principle of equivalent stiffness.What s more,the radius correction factor of the inclined rod which makes the load-displacement curve coincide was obtained by analyzing the simulation results of the original model and the equivalent model of the composite wall.(4)Parametric analysis of the thickness of EPS concrete slab or C30 concrete slab on the horizontal bearing capacity of composite wall structure.Under the influence of eccentric load and moment of inertia,the horizontal bearing capacity of composite walls and the thickness of wall panels showed a complex trend.Only when the thickness of wall panels and the width of beam-column flange were equal,the horizontal bearing capacity of composite wall was the maximum.(5)Based on the research results of this paper,some design suggestions for engineering popularization are put forward: In prefabricated residential buildings,section steel beams and columns can be selected with the same and smaller cross-section,meanwhile,the effective connections are formed between beams and columns through flat end plates,and the thickness of the wallboard is the same as the width of the flange.With the above design scheme,not only the assembly construction characteristics of the structural system can be brought into play,but also the high horizontal bearing capacity and l lateral resistant performance of the composite wall structure can be guaranteed.Therefore,the structural system has good application prospects in practical engineering.