VALIDITY AND APPLICABILITY OF TWO SIMPLE HYSTERESIS MODELS TO ASSESS PROGRESSIVE SEISMIC DAMAGE IN R/C ASYMMETRIC BUILDINGS
✍ Scribed by S.C. DUTTA; P.K. DAS
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 402 KB
- Volume
- 257
- Category
- Article
- ISSN
- 0022-460X
No coin nor oath required. For personal study only.
✦ Synopsis
The coupled lateral}torsional vibration in R/C asymmetric structures under seismic loading leads to larger lateral deformation in the load-resisting elements located at one edge, compared to the other resisting elements. This may cause earlier yielding of the elements of that edge in localized form. Strength and sti!ness degradation due to successive inelastic excursions of these R/C structural elements at one edge may make these elements more #exible and weaker as compared to those at the opposite edge. This may cause progressive shifting of sti!ness and strength centres away from this #exible edge, leading to consequent increase of e!ective eccentricity in successive loading cycles. This, in turn, causes a progressive increase in torsional e!ect in R/C structures. This damaging e!ect cannot be predicted by using the bilinear hysteresis models devoid of degradation characteristics. Existing sophisticated hysteresis models representing the degrading behaviour of the R/C structural load-resisting elements require a number of parameters to be speci"ed, the evaluation of which requires extremely case-speci"c calibration study. In this context, the present paper studies the suitability of two alternative simpli"ed hysteresis models, which are capable of predicting the strength and sti!ness degrading behaviours with simple input parameters. Responses of idealized asymmetric R/C building systems are studied using these two hysteresis models under design spectrum-consistent synthetic ground motions and idealized near-fault ground motions. The comparison between the responses of the R/C asymmetric structures with deteriorating structural elements and the similar structures having elasto-plastic structural elements proves the suitability of the proposed models in recognizing the progressive damaging e!ect of torsion in R/C asymmetric buildings.