DYNAMIC PERFORMANCE INVESTIGATION OF STEEL-CONCRETE STEEL SANDWICH BRIDGE DECK USING FINITE ELEMENT ANALYSIS SUBJECTED TO VEHICULAR LOADS

Abstract

This thesis aims at identifying the effect of speed of truck, shape of embossment of corrugated bottom steel and road surface roughness on the performance and strength capacity of Steel-Concrete-Steel (SCS) sandwich bridge decks. This simulation study aims to illustrate how big impediments like bumps and potholes affect a bridge when vehicle passing them on a road surface. The representation of tires is based on the simplest point-follower model. It has been demonstrated that the state of the road surface significantly affects bridge response. Approach thresholds, deck joints, cracks, potholes, and delamination are examples of road surface discontinuities that increase the impact pressures experienced by vehicles when they interact with bridges. Which class the bridge surface belongs to is unclear? Furthermore, it is exceedingly challenging to predict how the state of the road surface will alter in the future. Vehicle speed has a big impact on bridge response; as a result, as speed goes up, so does dynamic acceleration. Additionally, increased speed results in a substantial truck load bounce that is generated by even the smallest irregularities in the road surface, which increases vibration in the bridge. The finite element analysis result shows us increasing impactor velocity from 40km/h to 80km/h the central deflection increases by 12.013%, and when the velocity increase from 80km/h to 120km/h, the central deflection increases by 24.85% so, when the velocity increases the peak central deflection increases. The amount of vibration differs at different points along the length of the bridge. From this investigation, the behavior of the SCS sandwich deck slabs with different profiled sheeting is discussed. The best cold formed sheeting profile that suits the composite slabs is chosen among the simulation of three different arrangement of bottom corrugated profile. The re-entrant composite deck slabs’ have least deflections 9.93% and 17.3% lower than rectangular and trapezoidal profiled composite slabs, respectively. Deflection and slips of rectangular profiled slabs are lower compared to trapezoidal and flat profiled slabs. The finite element analysis result shows on the presence of surface obstacle increases central deflection. by 16.92%. The strain and stresses are lower for the re-entrant arrangement of bottom plate on composite slabs when compared to rectangular and trapezoidal profiled composite slabs. Generally, according to this study, on SCS sandwich structures using both stiffener and wearing surface can increase impact resistance capacity and manage to good energy absorption