International Research Journal of Mechanical Engineering

International Research Journal of Mechanical Engineering Vol.  3 (3) pp. 294-304, March, 2015. © International Scholars Journals

Full Length Research paper

 Probabilistic assessment of performance point in structures and examination of the instabilities

*Mehran Satrapi, Abbas F. Jobrani and Majid Amanpour

Department of Civil Engineering, Allameh Tabataba'i University,Tehran, Iran.


Accepted 21 February, 2014


The main goal of the performance based design of structures is to rationally predict the structures’ performance during earthquakes which may occur during the lifetime of the structure. In this sort of design, a specific displacement is defined as target displacement and the structure is subjected to a force in order to reach this target displacement. This design process includes uncertainties in loading, materials and analysis methods of the performance point. Therefore, statistical and probabilistic analysis should be considered. In this paper, uncertainty sources for determining the performance point are defined and then the procedures suggested in the codes are introduced. In the next step, an appropriate probability distribution function is defined for uncertainty parameters and finally the performance point of the structure is determined regarding these parameters in accordance with the codes. In addition, the sensitivity of the performance point with respect to the mentioned parameters is investigated. Results indicate that sensitivity of the performance point to geometric characteristics is of great importance and other parameters such as dead and live load stand in the second level in terms of sensitivity. An appropriate lateral loading pattern with the least uncertainty is also proposed for buildings.

Key words: Performance level, performance point, probabilistic design, uncertainty, sensitivity analysis.