对称加载作用下单箱双室组合结构的剪滞效应特性与试验研究

对于箱型组合结构,由于应力分布不均,极易导致翼板及底板发生剪切变形,从而对结构安全不利。为了深入探讨单箱双室组合结构中剪滞效应的机理,根据该类结构的受力变形特点,建立混凝土翼板和单箱双室钢梁的纵向翘曲位移模式,得到了控制微分方程及其边界条件,并推导出了在对称荷载作用下单箱双室组合结构的应变及挠度的解析表达式。开展了室内足尺寸模型试验,与剪滞效应理论进行了对比研究,应变、挠度计算值的最大相对误差分别达到15.32%和16.97%。可为该类结构中剪滞效应研究及单箱双室组合结构的工程设计、后期加固提供一定的参考。

Shear Lag Characteristics and Experimental Study for Simple-box Twin-cell Composite Structure under Symmetrical Loadings

Due to the uneven distribution on stress for composite box structures,it is easy to cause shearing distortions on wing-plate and bottom-plate,thus exert negative impact upon structures.In order to in-depth discuss the shear lag mechanism of the simple-box twin-cell composite structure,a longitudinal warping displacement model is established according to its mechanical property and deformation feature,and its control differential equations and boundary conditions are also obtained.What′s more,special solution expressions of strain and deflection for this type of structure are deduced under symmetrical loadings in this paper.By conducting full-scale model test,a comparative analysis with the shear lag theory is launched.The results show that the maximum relative errorson calculated values of strain and deflection are 15.32% and 16.97%,respectively.Finally,this kind of analysis method can provideguidance for composite structure engineering design and late reinforcement.