Experimental Investigation On Behaviorsof New Type Sandwich Panels

In this thesis, a new type light-weight composite sandwich wallboard with property of environment protection was designed and investigated for satisfying the requirements of a new structure system called wall-beam-column structure system. In this structure it is used to not only carry loads but need to form composite beam and column.According to the different behavior characteristics of different positions in this structure, this wallboard has two detailing forms. One is used at the corner and end positions of building walls to form a frame column and strengthened by profiled steel (called as shaped-steel wallboard), the other is used in those positions except for the former wallboard positions and strengthened only by steel bars (called as steel-bar wallboard). The former can carry horizontal and vertical loading, and the latter mainly carries vertical loading.A total of 22 specimens were cast and tested, including 9 shaped-steel wallboards and 13 steel-bar wallboards. The failure mode, strength and deformation of these specimens under axial compression loading with different eccentricity or horizontal loading with different axial compression ratios were examined and analyzed.The failure of the steel-bar wallboards was sudden with crisp noise and it can be seen that when the wallboard failed some concrete block will collapse off it, so this type wallboard had a typical brittle failure mode. But its capacity bearing axial compression was relatively high. With the increase in eccentricity of loading, the wallboard bearing capacity decreased and the failure became slower. The behaviors of shaped-steel wallboards are different from those of the steel-bar wallboards. They not only belong to ductile failure but have higher bearing capacity compared to steel-bar wallboards. The decrease of the bearing capacity with the increase in eccentricity of loading was also slower than the former. For horizontal loading, all specimens' capacity bearing loading varied as axial compression loading applied to them changed. But the shaped-steel wallboard has higher capacity and better ductibility than steel-bar wallboard for such loading conditions.A simplified design calculating method for the two kinds of wallboards mentioned above is developed and the corresponding formulas are given in this paper based on the experimental and theoretical analysis results. It is shown that a good prediction for the bearing capacity of the wallboard can be given using this method, and it is suitable to use this simplified method for the analysis of this wallboard.Form the experimental results of the wallboards, the corresponding theoretical analysis and the comparison of the bearing capacity to brickwork wall, it is shown that the new type wallboards can satisfy the requirements of wall-beam-column structure system.