Technical gazette, Vol. 21 No. 2, 2014.
Original scientific paper
Performance based design and damages estimation of steel frames with consideration of uncertainties
Fardin Azhdary
; Department of Civil Engineering, University of Sistan and Baluchestan, Zahedan 9816745437, Iran
Naser Shabakhty
; Department of Civil Engineering, University of Sistan and Baluchestan, Zahedan 9816745437, Iran
Abstract
Damage levels of the structure and their corresponding displacements could be presented both qualitatively and quantitatively (based on the performance-based design method). For quantitative evaluation of seismic damage level in structures, damage index is used. Researchers have proposed several functions based on the nonlinear dynamic and cyclic behaviour of the structural members for quantitative evaluation of damage. On the other hand, for evaluation of damage index, various uncertain parameters such as load and resistance exist. In this paper, a modified damage index is introduced based on the reduced stiffness of the structure. Results from the modified damage index are compared with those indices which are based on energy and the period of the structures. Results show that the proposed damage index is an appropriate factor for damage evaluation of steel structures specially. Three groups of structures including 3, 6 and 12 stories structures and also their uncertainties and probabilistic sources were considered. The damage index and the drift of the structure for each performance level were determined. Sensitivity of the damage index with respect to the uncertainties parameters in performance level is indicated. Furthermore, the quantitative damage of the structures with their corresponding drifts is obtained. The obtained results show that the geometric characteristics of structural elements have a great influence on the sensitivity of damage index of structures. When a number of stories increase, this value and corresponding drifts will be reduced. Number of stories has an inverse influence on sensitivity.
Keywords
damage index; performance levels; probabilistic analysis; pushover analysis; uncertainty
Hrčak ID:
120387
URI
Publication date:
26.4.2014.
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