NUMERICAL INVESTIGATION OF STEEL-CONCRETE-STEEL SANDWICH COMPOSITE BEAMS SUBJECTED TO IMPACT LOAD

Abstract

This research work is dedicated to numerically investigating the impact load response of Steel Concrete-Steel composite beams using finite element software program LS-DYNA. The experimental result reported in the literature is used for the validation analysis of LS-DYNA finite element software program. The FEA result is good agreement with experimental results. The parametric study of this research work is type of mechanical shear connectors, span to depth ratio, steel plate thickness and yield strength. FEA result shows that, from the three of shear connector type used on this thesis truss like shear connects have good impact load resistance and minimum central deflection resistance than the other shear connectors (J-Hook and Bi-steel). The maximum impact force increases up to 17% and there corresponding central deflection reduced to 14% when the thickness of plate increases from 4mm to 6mm, and the thickness increases from 4mm to 8mm maximum impact load increases up to 32% and central deflection reduced to 22%. Increasing yield strength for enhancing impact load resistance of SCS composite beams is more effective in thicker plates compared to thinner plates. As the yield strength increases from 235Mpa to 355Mpa the impact force enhances by 14% for thicker plate (8mm), while it 9% for thinner plate (4mm). Yield strength of steel plate has negligible influence on the effect of plate thickness in impact force resistance and beam deflection of SCS sandwich composite beams. Span to depth ratio have relatively high influence on central deflection than impact load response of SCS sandwich composite beam. When the span to depth ratio increases from 6.25 to 18.75 the central deflection of the beam increase by 72% and impact load resistance reduced by 38%.