考虑内力分项贡献度的框架构件重要性评价

摘要

提出了一种水平和竖向荷载共同作用下的框架结构构件重要性评价方法.首先,基于线弹性材料假设,利用应变能方程和节点-外荷载关系计算梁柱构件的轴力、剪力和弯矩;然后,定义构件内力分项计算值与抗力分项值之比为构件分项重要性系数,用于体现构件抗力利用水平;再组合各内力分项系数,针对不同外荷载形式定义构件综合重要性系数,用于体现构件对框架体系整体承载力的贡献;最后,通过两榀框架算例验证了方法的可行性,可为框架的结构优化设计和连续性倒塌分析提供定量依据.%A component importance evaluation method for frame structures under horizontal and vertical loads is developed in this paper.The strain energy equation,together with the node-external force relationships of frame components,is first used to calculate the axial forces,shear forces and bending moments of beams and columns.Then component-level partial importance coefficients are defined based on the ratios between the calculated internal forces of components and their resisting forces.The coefficients embody the utilization levels of the resisting forces of components.Subsequently integrated importance coefficients are defined using the combinations of different partial coefficients,which reflect the component contributions to the entire load capacity of a frame structure.Lastly,the feasibility of the developed method is verified against two different frame structures.The analysis results demonstrate that the method can provide quantitative evaluations for the optimal design and the progressive collapse design of frame structures.