Theoretical And Experimental Research On Lateral Performance Of Load-bearing And Thermal Insulation Integration Of Prefabricated Steel Structure Residence

In order to realize the goal of load-bearing and thermal insulation integration of prefabricated steel structure residence,a new type of load-bearing and thermal insulation integration wall with concealed bracing is proposed: the load-bearing thermal insulation integrated wall with concealed brace.The wall is made of foam concrete for braced steel frames,and a layer of reinforcing steel mesh is arranged on both sides of the wall,and mortar protection layer is poured.The integrated wall combines the vertical bearing member and horizontal bearing member,which has the double functions of bearing and heat preservation.In order to study the lateral performance of the load-bearing and thermal insulation integration wall of prefabricated steel structure residence,this thesis makes theoretical and experimental research on the lateral performance of the integrated wall.Firstly,the low cycle repeated loading tests were carried out on 8 single story single span bearing and insulation integrated walls with the parameters of concealed brace setting,wall thickness and wall height width ratio.The horizontal bearing capacity,lateral stiffness and hysteresis characteristics of each specimen were obtained.The results show that the structure of the load-bearing and thermal insulation integration wall of prefabricated steel structure residence can ensure that the width of the crack is less than 0.2 mm at the displacement angle of1/400.The lateral stiffness of the integrated wall with load bearing and insulation is 2.10 times that of the pure braced steel frame,and its horizontal bearing capacity is 1.76 times that of the pure braced steel frame.The influence of foam concrete on braced steel frame should be considered in the design.The ratio of height to width has a significant influence on the lateral performance of the integrated wall.The larger the ratio of height to width,the smaller the horizontal bearing capacity,lateral stiffness and energy consumption capacity of the wall.Secondly,through theoretical analysis,the equivalent diagonal strut model,superposition model and equivalent brace strengthening model are used to deduce the practical calculation formulas of horizontal bearing capacity and lateral stiffness of load-bearing and thermal insulation integration wall.The energy method and vertex displacement method are used to calculate the periodic reduction coefficient of multi-layer integrated wall structure.Based on the superposition model,the unidirectional fiber reinforced model of composite material is used to equivalent the wall to isotropic homogeneous material.The ratio curve of wall height to width to shear displacement is deduced,and the boundary height width ratio of load-bearing and heat preservation integrated wall is calculated.The results show that the equivalent diagonal strut model,superposition model and equivalent support strengthening model can get better results;The calculated value of the periodic reduction coefficient of the structure is between 0.69 and0.80,and the periodic reduction coefficient decreases with the increase of the wall thickness;When the height width ratio of the boundary of load-bearing and thermal insulation integration wall is 1.0 and 3.0,the height width ratio is less than or equal to 1.0,it is considered as a short wall,and the lateral displacement deformation is mainly shear deformation.When the ratio of height to width is greater than 1.0 and less than 3.0,it is considered as the middle wall,and the lateral displacement deformation is a comprehensive bending shear type.When the ratio of height to width is greater than 3.0,it is considered as high wall,and the lateral displacement deformation is mainly bending deformation.Finally,the fine model,simplified model and wire model of integrated wall are established by using ABAQUS finite element software,and static loading simulation is carried out.The wire model of multi-layer multi span integrated wall structure is established,and the frequency analysis is carried out based on the equivalent support strengthening model,and the periodic reduction coefficient of multi-layer multi span integrated wall structure is obtained.The results show that the load displacement curves of the refined model,simplified model and wire model are basically in accordance with the test skeleton curve,which shows that the three models can simulate the horizontal bearing capacity of the integrated wall of bearing envelope and insulation;The period reduction coefficient of multi-layer multi span integrated wall structure is between 0.81 and 0.88.