notes on progressive collapse analysis of modular moment frames under directional effects of pulse-type ground motions

In recent years, seismic design of structures has been accompanied by global changes in conceptual criteria from the resistance lemma to the performance subjects. the most notifications related to performance concepts are essentially categorized in; 1- thedesign and evaluation of structural seismic demands, 2- the characteristics of earthquakes and their effects on the code-design structures. the main purpose in codified structural designation is achieving to the enough strength and stiffness capacities which to keep the structure stable under the most critical loading conditions over its lifetime.