局部加劲钢套管加固钢筋混凝土柱的研究

Retrofit of reinforced concrete columns using partially stiffened steel jackets

本文介绍了一种改进的钢套管加固现有柱的方法,将薄钢板焊接成一个环箍套管,以提高柱的抗剪强度,然后可选择不同类型的约束部件(加劲元件)焊接在可能产生塑性铰的部位,以增加柱的延性。所提出的设计计算方法通过了5根1/3比例的模型柱试验验证,试验加载条件为在0.3Af'的固定轴力下,施加水平往复荷载。试验结果表明:局部加劲钢套管不仅可以预防脆性的剪切破坏,还可以大幅提高柱的延性,可使最大侧移率超过8%。该加固方法可使方形或矩形截面混凝土柱的强度与延性得到良好的改善。

This paper introduces an improved steel jacketing method to retrofit reinforced concrete columns. To retrofit an existing column, relatively thin steel plates were welded to form a rectilinear jacket for shear strength enhancement, and then additional confinement elements (stiffeners) were welded to the potential plastic hinge regions to ensure a ductile behavior. A rational retrofit design procedure was proposed and evaluated through an experimental program. Five 1/3 scale model columns were tested under constant axial load of 0.3Afc and cyclic lateral force in a double curvature condition. Test results validated the efficiency of the partially stiffened rectilinear steel jacketing, which not only prevented brittle shear failure but also greatly improved the ductility of the column.