中文摘要：

结构鲁棒性意为结构在偶然事件中发生局部损伤而不产生与损伤起因不相称的破坏的能力，其量化理论目前仍较为匮乏。该文首先提出了易损构件的定义，推导了单一均质材料矩形截面构件考虑轴力、剪力与弯矩受力相关性的构件易损系数计算公式。对处于轴力、剪力与弯矩复合受力状态下的钢筋混凝土矩形截面构件，可以类似地得到其相应的构件易损性系数计算公式。根据已有的关于构件重要性系数的研究，该文提出了一种新的结构鲁棒系数对鲁棒性的量化。最后，对一个平面桁架和一个平面框架进行计算以阐释鲁棒性系数的应用。由分析可知，降低构件的重要程度和降低关键构件的易损程度是加强结构鲁棒性的两种有效途径。

英文摘要：

Structral robustness means that a structure has the ability to avoid damages disproportional to the initial local damages when suffering accidental events. From previous research, few quantitative theory of robustness has been proposed. In this paper, the definition of the vulnerable component is proposed. The calculation formula of the vulnerability coefficient of homogeneous rectangular component under axial force, shear and flexure is derived. Similarly, the vulnerability coefficient for rectangular reinforced concrete （RC） members under the combined loadings of axial force, shear and flexure is also obtained. Then, according to the theory of the vulnerability coefficient of component in existing research, a new robustness index used for evaluating the robustness of structure is proposed. Finally, a planar truss and a planar frame are calculated to illustrate the application of the robustness index. From the analysis, it can be concluded that reducing importance coefficinents of components and decreasing vulnerability coefficients of components are two effective ways to enhance structural robustness.