No abstract

No abstract

Abstract. The latest earthquake disasters have highlighted, once again, poor functioning of the existing masonry structures, and the need to intervene all these structures which have been designed with old regulatory criteria, inadequate or those that have been built before the emergence of design codes. The significant progress made in new criteria of earthquake resistant design, should be extended to all the existing structures, it is therefore essential to identify the degree of seismic performance. Unreinforced masonry (URM) buildings represent a significant portion of the residential structures in Algeria, accounting for more than 60% of existing buildings. In addition to significant population, the brittle nature of URM buildings further supports a thorough consideration of seismic response given the susceptibility to severe failure modes. Currently, there is a pressing need for analytically based fragility curves for URM buildings. In order to improve the estimation of damage state probabilities through the development of simulation-based masonry fragilities, an extensive literature survey is conducted on pushover analysis of URM structures. Structural response is evaluated using an advanced capacity spectrum method. Capacity, demand, and response are thus derived analytically and response data is used to generate an improved and uniform set of fragility curves for use in risk assessment. Seismic fragility curves are expressed in multiple forms for wide range of use in loss-assessment applications. Results are discussed and compared with other relationships developed in the literature.

No abstract

Abstract. This study focused on the probabilistic risk assessment of reinforced concrete piers bridges subjected to ground motion excitation. In order to assess the vulnerability of Piers Bridge, a case study of a typical Algerian highway bridge is presented, illustrating the seismic performance and damage evaluation method. Pushover and incremental dynamic analysis using several earthquake records is implanted to determine the fragility curves reflecting the probability of various damage occurrences. These fragility curves provide the probability of exceeding the multiple damage states for a given intensity of ground motion excitation. To develop the fragility curves, a nonlinear static pushover and incremental dynamic time-history analysis have been performed using the SeismoStruct nonlinear analysis program for bridge model to develop fragility curve, this study includes comparison between real or artificial ground motions selection, IDA is performed using a set of 18 real ground acceleration records and 8 artificial ground acceleration records of similar seismo/geological origins. Finally, the developed fragility curves can be used to assess the seismic performance of Piers Bridge and help to decision making for effective retrofitting technique.