Davoud Layegh Rafat - Department of Civil Engineering, Zabol Branch, Islamic Azad University, Zabol, Iran
Mohsen Rigi - M.Sc , Department of Civil Engineering, International University of Chabahar, Iran
Mohammad Anvar Rigi - M.Sc, Department of Civil Engineering, Zahedan Branch, Sistan and Baluchestan University, Iran
morteza laygh rafat - M.Sc, Department of Civil Engineering, Zahedan Branch, Sistan and Baluchestan University, Iran

For a ling time, structures, due to their lightness, were believed to be invulnerable to earthquake. While the Koobe earthquake in Japan in 1995 revealed that such structures should not be expected to be absolutely immune. To this end, the capacity spectrum method was utilized to evaluate the earthquake effect on the behavior of space structures. Such method gives the maximum result regarding the structure capacity and requirement based on acceleration and displacement. The comparison between the earthquake acceleration real spectrum and capacity spectrum methods was intended in this paper. The efficiency of the latter method for determining performance stages of space structures was then defined as the target point displacement. Having obtained the points of performance stages, that is, I.O or L.S and/or C.P., one could find structure weak points. To this end, after loading and selecting appropriate parameters, several structures with different heights and spans are examined from the viewpoint of static and dynamic analyses. The results indicate that the capacity spectrum method has rendered an acceptable appraisal onnon-linear dynamic analysis.

One layered space drums; Performance stage; Capacity spectrum; space structures; spacestructures; dynamic analysis; spectrum method