University of Tehran Civil Engineering Infrastructures Journal 2322-2093 48 1 2015 06 01 Seismic Fragility Assessment of Special Truss Moment Frames (STMF) Using the Capacity Spectrum Method 1 8 53703 10.7508/ceij.2015.01.001 EN Gholamreza Abdollahzadeh Associate Professor, Faculty of Civil Engineering, Babol University of Technology Mohammad Sazjini Ph.D. Student, Faculty of Civil Engineering, Babol University of Technology Azadossadate Asghari Ph.D. Student, Faculty of Civil Engineering, Babol University of Technology Journal Article 2013 03 11 Fragility curves represent the probabilities that structural damages, under various levels of seismic excitation, will exceed the specified damage states by means of earthquake intensity damage relations. Conceptual aspects related to seismic vulnerability, damage and risk evaluation are discussed first, together with a short review of the most widely used possibilities for the seismic evaluation of structures. The capacity spectrum method starting from capacity and fragility curves is then discussed. The determination of capacity curves for buildings using a non-linear structural analysis tools is then explained, together with a simplified expeditious procedure allowing the development of fragility curves. Next, the seismic risk of the special truss moment frame (STMF) systems of Tehran, the capital of Iran, is analysed in this paper using the capacity spectrum method. The seismic hazard of the studied area is described by using the reduced 5%-damped elastic response spectra. Significant damage is obtained for mid-rise and high-rise special truss moment frames with a Vierendeel middle panel, because of the buckling and early fracture of truss web members. Special truss moment frames with an X-diagonal middle segment also show a low seismic capacity leading to significant expected damage. https://ceij.ut.ac.ir/article_53703_4fc71a2783acbae075399f4c97135e58.pdf