Economic Evaluation of Design of the Steel Moment Frame System against Blast Load Using Both Load and resistance factors (LRFD) and Performance Based Methods

One of the most important characteristics of a good structural design is its economic and optimal design against applied loads. Nowadays, with the increase of terrorist attacks, the economic design of buildings against blast load is important. Thus in this study, the effects of design methods on the economic design of steel moment frames with different number of floors against blast loading is evaluated. The studied frames were modeled in SAP2000 and were analyzed using linear and nonlinear dynamic methods. To ensure the accuracy of simulation, the model was first evaluated by a validated numerical studies and reasonable agreement was observed between them. Each of the structural models has been analyzed and designed using load and resistance factor design method as well as performance-based design method. Results show that in the low-rise frames, the performance based design method leads to more economical design (10 to 42 % depending on the severity of the blast load and the number of floors) in comparison with the load and resistance factor design method; but by increasing the number of floors, the load and resistance factor methods is more economical than the performance based design method.