组合板剪切粘结机理及承载能力试验

压型钢板与混凝土界面的纵向剪切粘结破坏是组合板最为常见的破坏方式.端部锚固明显改善了组合板的纵向剪切粘结承载特性.当前的计算方法,如m-k法和部分连接法对此考虑并不充分.进行了13块足尺组合板的承载力试验,通过组合板的挠度、端部滑移和截面应变分布等试验结果,揭示了组合板剪切粘结破坏机理,分析了端部栓钉锚固、跨度、板厚和剪跨长度对组合板剪切粘结承载力的影响.根据组合板截面的内力及变形几何关系,得到了压型钢板与混凝土界面纵向剪力与竖向剪力的关系.对m-k法和部分连接法进行了分析比较,根据组合板界面剪切粘结极限状态,对部分连接法方法进行了改进,其计算结果与试验结果吻合较好.

Experimental Investigation on ShearBond Mechanism and Strength of Composite Slabs with Steel Profiles

In most cases,strength of composite slabs is governed by shear-bond failure at the sheeting-concrete interface.Considerable improvement of longitudinal shear-bond load carrying characteristic is acquired for composite slabs with end anchorage.However,current design procedures to assess the shear-bond strength,such as the m-k method and the partial connection method(τu),are not considerate for the influence of end anchorage.Thirteen full scale simply supported composite slabs were tested by varying the influence parameters like span length,slab depth,shear span length and the end anchorages which was provided by the steel headed studs.Based on an analysis of deflection,end slip and the distribution of strain of the cross section,the shear-bond failure mechanism of composite slabs is revealed.In terms of the internal force and deformation relationship,the sheeting-concrete interface longitudinal shear force is revealed in the term of vertical shear force.The test results were appraised using present design procedures.Based on the ultimate shear-bond state,a simplified method is proposed for τu method.The method has been validated and the results predicted by the simplified method agree well with the test results.