Study And Application On Shear Behavior Of Cold-formed Thin-walled Steel Composite Wall

The composite wall is the main force component in the cold-formed thin-walled steel structural system,and the connection of the panel with the self tapping screw is one of the main factors for the performance of the composite wall.The panels of composite wall are oriented particleboard,plywood,thin steel plate and corrugated steel plate,etc.In this paper,the composition and application of the structural system are introduced,and through test and finite element analysis to study the impact of parameters on the shear behaviors and the connection performance of the composite walls.The main content are as follows:Firstly,the framing,connection structure,load effect and its transmission path,design points were introduced: the framing consist of foundation,walls,floor cover and roof,the structure's load transfer path is improved by a reliable connection between the members.The architectural design,determination of design parameters,the connections between walls and foundation,the selection of wall members' type and the layout of members,the advantages and defects of different types of panel were introduced by a project example,then a comprehensive economic analysis of this structural system was made by citation.Secondly,through 16 groups of monotonic tensile test of the connections between the woody sheathing panels and cold-formed thin-walled steel,the influence of the connection parameters on connection performance was analyzed,such as OSB and Plywood,panel strips,screws distance to board end,texture and damp.The test results show that the shear strength of plywood-specimen is about 25% and 26% higher than that of OSB-specimen under the condition of vertical and horizontal texture,the texture has no significant effect on the shear strength of plywood specimens.Comparing with whole sheathing specimens,the shear strength and elastic stiffness of the strip sheathing specimens are lower,and the capacity of the strip sheathing specimens is greatly reduced.The shear strength of plywood-specimen is increased obviously with screw to board to end distance in the range of 3d(15mm)-5d(25mm),from 5d(25mm)to 7d(35mm),the shear strength of the specimen did not change significantly,but the ductility,the peak and limit displacement are still increased obviously.After the OSB,Plywood were damped,the shear strength of specimens decreased obviously,the ductility increased slightly;the impact of damp on the connection performance of the OSB specimen is more significant,mainly in elastic stiffness;increasing the end of the screw plate of dampness specimens from 5d(25mm)to 8d(40mm),the specimen of OSB shear strength and elastic stiffness no changes,ductility,peak and limit displacement increased slightly,the specimen of plywood characteristic parameters no significant changes.The connection test is the reference for defining the connection strength in the finite element analysis of composite walls.Lastly,through finite element analysis of the composite walls by ABAQUS to analyze the effect of the wooden plate,the thickness of thin steel plate,the thickness of frames,the type of corrugated steel plate,ratio of height to width,the size and geometry of the hole of corrugated steel plate on the shear performance of composite walls.The results show that the shear strength and initial stiffness of walls are increased significantly by increasing the thickness of the thin-walled steel panels or using the corrugated steel panels;the shear strength of the composite wall sheathed with 12 mm thickness OSB is greater than the 0.84 mm thickness thin-walled steel walls and less than the 1.00 mm thickness thin-walled steel walls,the shear strength and initial stiffness of the 12 mm thickness Plywood wall are equivalent to the 1.00 mm thin-walled steel wall;the shear strength and initial stiffness of the composite walls sheathed with dampness OSB and Plywood decreased about 30%,the decline is equal;the thickness and arc flange cross section of the stud has little effect on the shear strength and initial stiffness of the composite wall;in the corrugated panels analysed in this paper,the composite walls sheathed with MINO900-corrugated steel have the highest shear strength and initial stiffness,the composite walls sheathed with AC780-corrugated steel have the minimum shear strength and initial stiffness;the proper size of the hole can reduce the initial stiffness,improve the post-buckling performance and ensure the shear strength of the composite wall;the area of the hole of the corrugated steel plate has a significant effect on the shear performance of the composite walls,but the circular and square holes have little difference on the shear performance;whether the aspect ratio of height to width is 4:1 or 2:1,the shear strength and initial stiffness of the composite walls sheathed with horizontal corrugated steel sheets are higher than the vertical ones,the nominal shear strength is decreased slightly and the initial stiffness is increased significantly with the aspect ratio of height to width is 4:1 to 2:1.