Research On Cold-formed Thin-walled Steel Two-way OSB Board Composite Floor

Wood as a green building material with a light weight,high strength ratio（strength/specific gravity）,environmental protection and many other advantages,but wood has original knot defect and its nail holding ability is poor.Compared with wood,OSB board has better nail-holding ability,higher bending strength,and smaller linear expansion coefficient.At the same time,it also has environmental protection characteristics such as heat preservation and heat insulation and low life cycle energy consumption.Steel has many advantages such as light weight,high strength and good ductility.The capacity of the coldformed thin-walled steel two-way OSB board composite floor’s flexural bearing is studied,and ABAQUS finite element analysis is performed on it.The research content of this paper mainly includes the following aspects:（1）The research status of two different building materials including cold-formed thinwalled steel and OSB board and steel-wood composite floor is summed up;（2）The material performance test of cold-formed thin-walled steel and OSB board was completed.According to the measured data,various mechanical parameters were acquired,which as parameter basis for the subsequent finite element analysis.（3）A new type of combined two-way load-bearing floor composed of cold-formed thinwalled steel and OSB board connected by self-tapping screws is proposed,and the monotonic static stacking test is carried out on the full-scale floor.The whole process of the composite floor test is introduced,including the design and manufacture of specimens,the test loading device and the test scheme,and the arrangement of measuring points.Not only acquired the change trend of strain and deflection,but also observed the entire failure process of the composite floor.The combined performance and bearing capacity of the specimens were gained.The research indicated that the two materials,OSB plate and cold-formed thinwalled steel,can work well together and coordinate deformation.The two main load-bearing components of the specimen,the combined load-bearing beam along the X axis and the combined ribs along the Y axis,provide the same force to the combined floor.It shows that the two-way floor has good working performance and stable structure.（4）Using ABAQUS finite element software,the flexural performance of composite floor under the condition of simply supported on four sides is numerically analyzed,and the variation characteristics of strain and deflection of composite floor under the action of vertical uniform load are analyzed.The finite element calculation data and the experimental data are similarly which proved the correctness and feasibility of the finite element model.Research shows that increasing the height of the OSB beam web,increasing the thickness of the steel plate,and reducing the screw spacing can improve the flexural bearing capacity of the composite floor to varying degrees.（5）The calculation method of flexural bearing capacity of composite floor is put forward,and the calculation formula for the deflection of the test piece in the middle of the span and the flexural bearing capacity are proposed.The theoretical analysis and calculation results are in tuned with the experimental results,and the data error is well controlled within15%,which can be used in practical engineering design and calculation.