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        1 - A Numerical Study on the Seismic Performance of a RC-Bridge With Random Pier Scouring
        Ali Raoof Mehrpour Hosseini Mehran Seyedrazzaghi Nasser Shamskia
        A multi-hazard investigation approach is a vital requirement for a realistic risk assessment of infrastructures. The combined impact of scouring and earthquake can result in a distinctive effect on the performance of a given bridge. Scouring, being a hazard influenced b More
        A multi-hazard investigation approach is a vital requirement for a realistic risk assessment of infrastructures. The combined impact of scouring and earthquake can result in a distinctive effect on the performance of a given bridge. Scouring, being a hazard influenced by various factors, entails numerous uncertainties. Several prior investigations have explored the multi-hazard of scour-earthquake; however, the associated implementation has not accounted for the random scour depths around the foundations of differing bents. This study provides a probabilistic platform to investigate the effect of random scouring on the seismic performance of a multi-span RC bridge. In this regard, researchers employed Monte Carlo simulation to develop a probability hazard curve for scour. The Latin Hypercube technique was applied to randomly select depths, enabling the generation of non-uniform patterns for the depth of cavities formed in different foundations. Subsequently, the study involved conducting non-linear time history analyses on the finite element model. The uniform scouring patterns were also examined to compare the models. The scouring around foundations significantly affects the responses of bridge elements, as it influences the total base shear of the structure and the pounding forces between the superstructure elements. Manuscript profile
      • Open Access Article

        2 - Seismic Fragility Analysis of a RC Bridge with Uniform and Non-Uniform Random Scour Patterns
        Ali Raoof Mehrpour Hosseini Mehran Seyedrazzaghi Nasser Shamskia
        Previous natural disaster assessments had identified bridges as vulnerable structures against hydraulic hazards, particularly scouring. Additionally, in areas with high seismic activity, bridges are exposed to minor damage to complete collapse, in most cases requiring i More
        Previous natural disaster assessments had identified bridges as vulnerable structures against hydraulic hazards, particularly scouring. Additionally, in areas with high seismic activity, bridges are exposed to minor damage to complete collapse, in most cases requiring immediate occupancy structural performance levels in the event of an earthquake. Previous studies have focused on vulnerability assessments by considering the effects of simultaneous hazards. This study examines a simply supported RC bridge model with a discontinuous deck-girder superstructure installed on cap beams via elastomers. Seismic vulnerability assessments were conducted by developing fragility curves through nonlinear time history analyses on scoured models. One of the study's objectives is to consider the effects of non-uniform patterns in different foundations of the four-span model by generating random depth samples. The study also evaluated even depths as the uniform scenario for vulnerability assessment. The results indicate that, in all limit states considered in the study, the uniform has a higher probability of exceeding the limit states than the non-uniform scenario. However, in evaluating critical scoured models, the uniformly maximum credible scoured pattern did not necessarily have a higher probability of exceeding all limit states. In other words, the non-uniform scenario, which had pier(s) with the maximum credible scour depth, had a more critical vulnerability in some limit states. Manuscript profile