Endurance Time Analysis of skewed slab-on-girder bridges: The significance of the excitation angle

Document Type : Article


Department of Civil Engineering, Sharif University of Technology, Tehran, Iran


In this paper the influence of excitation angle on the Endurance Time (ET) analysis of skewed slab-on-girder bridges is studied. The excitation of the structure due to critical angle leads to the maximum seismic responses that are sometimes significantly higher than the average. The modeled bridges are slab-on-girder type which are typically used as highway bridges. The bridge models have skew angles of 0, 15, 30, 45, and 60 degrees. The ET excitations exerted on the structures cover a broad range of hazard levels. The results provide some insight for choosing multiple excitation angles in such a way that balances computational costs and retains acceptable accuracy for practical design purposes. Sensitivity of life cycle cost (LCC) to skewness is also studied.


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