"DYNAMIC ANALYSIS OF SKEW EFFECTS ON SLAB GIRDER AND T-GIRDER BRIDGES"

Abstract

The phenomenal growth of the industrialization in last three decades has resulted in a great increase in vehicular traffic on roads and bridges. To this end, the bridges are required to withstand the heavy loads imposed by modern heavy vehicles with utmost safety and economy. Bridges at varying skew angle and with some curve are frequently observed to provide the most suitable alignments. This requires the construction of skew bridges. Skew bridges are commonly used at highway intersections as overpasses. Several types of seismic failures of skew bridges have been observed due to severe earthquakes, such as pier distress, deck unseating, expansion joint failure, etc. This work involves the Static and Dynamic analysis of single lane and two lanes of Slab Girder Bridge and T-Girder Bridges using FEM. Modelling was done, by adopting the typical bridge configuration using shell element and Beam element for four bridge system. Around 20 models were created and analysed Here the Static and Dynamic Parameters studied by varying skew angle under the action of dead; IRC vehicle load and Seismic load (Response Spectrum) are shear force, bending moment, torsion, deflection, time period, mode shapes, modal participation factor and displacements. From this study, it is clearly understood that as the skew angle increases the design parameter such as Bending moment, Shear force and Torsion increases considerably. The vertical deflection along the centre of longitudinal axis decreases as the skew angle increase from 0° to 60°. Fundamental time period and Base shear from the free vibration analysis and response spectrum method respectively shows decrement as the skew angle increases from 0° to 60°. The values have been presented in the tabular as well as in graphical form.