节点域尺寸对H型钢截面局部钢框架塑性损伤规律影响的分析

Analysis of the Influence of the Panel Zone Size on the Plastic Damage Law of the Local Steel Frame with H-section

为了研究节点域尺寸对H型钢截面局部钢框架塑性损伤规律影响,以常见的梁、柱及节点域组成的十字形钢框架结构为分析对象,以H型钢柱截面类型、轴压比、节点域高宽比、节点域宽度与层高比、节点域高度与跨度比及结构跨高比等为主要研究参量;基于力学平衡准则进行分析。结果如下:如果用不考虑节点域尺寸时构件的强度来判断柱、梁及节点域组成的框架节点的破坏机制(塑性铰形成位置),可能会出现误判;H型钢截面局部钢框架的节点域与柱强度比,随轴压比和节点域高宽比的增大而增大,而随跨高比的增大而减小。柱为宽翼缘H型钢时,节点域先于柱形成塑性铰;柱为中或窄翼缘H型钢时,轴压比为0.6及节点域高宽比等于2时以外,基本上节点域先于柱形成塑性铰;轴压比小于等于0.4时,H型钢柱强度是节点域强度的1~5倍,可能导致实现"强节点域"的构造处理施工的困难。

In order to study the the influence of the panel zone size on the plastic damage law of the local steel frame with H-section, taking the cross-shaped steel frame structure which is composed of the common beam, column and panel zone as analysis object, cosidering the secton type of the H-steel column; the axial compression ratio; the height-width ratio, the width-storey ratio and the height-span ratio of the panel zone and the span-height ratio of the structure as the main study parameters, analysis is implemented based on the mechanical equilibrium criterion. Results show that the misjudgement may be made if the strength of the member which do not concider the panel zone size is used to judge the damage mechanism of the frame node composed of the column, beam and panel zone ; the ratio of the panel zone to the strength of the column increase with the axial compression ratio and the heigth- width ratio of the panel zone,decrease with the increase of the span-heigth ratio of the panel zone; the panel zone form the plastic hinge prior to the column when the column has the section of H-type with wide flange, the same situation can be obtained with the exception of the H-section with middle or narrow flange, the axial compression is equal to 0-6 and the heigth-width ratio equals 2; the strength of the panel zone is 1 -5 times the strength of the column when the axial compression less than or equal to 0. 4, which may result in the difficulty in the construction of the structure treatment that realizing the strong panel zone.