考虑跨中塑性铰的钢框架结构非线性分析

Nonlinear Analysis of Steel Frames with Elements of Plastic Hinge at Midspan

给出一种考虑跨中塑性铰的钢框架结构的非线性分析方法 ,该方法可以通过 1单元 /杆件来分析杆件上有分布荷载 ,从而可能会在杆件内部形成塑性铰的情形 .除此之外 ,该方法还可以考虑轴力的二阶效应、剪切变形、横截面塑化、残余应力、初始缺陷等几何和材料非线性因素的影响 ,既克服了塑性区法因单元划分过多而花费机时的缺陷 ,又弥补了塑性铰法不能考虑横截面塑化及仅在单元两端形成塑性铰的不足 .计算分析表明 ,结果令人满意 .

A nonlinear analysis method of steel frames with elements of plastic hinge at midspan is proposed. This method can analyze the case that there are distributed loads on members so that a plastic hinge may appear within the member only using one element to model one member. What's more, this method also considers the influences of some geometrical and material nonlinear factors including second-order effect of axial forces,shear deformation,cross-section plastification,residual stress and initial imperfection. This method not only overcomes the time-consuming defect of plastic zone method because of the fine mesh discretization but also makes up for the insufficiencies that cross-section plastification can not be considered and plastic hinges can only form at element ends. Analysis results show that the proposed method is satisfactory.