Seismic Behaviour of Steel-Fibre-Reinforced GGBS Concrete Beam-Column Joints

Beam-column joints play a crucial role in the structural behaviour of framed structures. Use of highly ductile material and addition of steel fibres to concrete will enhance the seismic resistance of beam-column joints. It has been observed that addition of Ground-Granulated Blast furnace Slag (GGBS), a byproduct from the steel industry, will provide more ductility and durability to concrete. Addition of GGBS as a partial replacement into concrete reduces the disposal issues and minimise the carbon footprint. The seismic studies reveal that in a reinforced structure, the failure of beam-column joint is critical during earthquakes. Ductile behaviour of GGBS concrete will enhance the seismic performance of beam-column joints This paper aims at investigating the feasibility of using GGBS as a partial replacement to cement in steel fibre reinforced concrete composites. Experimental investigations were conducted on exterior beam-column joints made of steel-fibre-reinforced GGBS concrete. Optimum percentage replacement of cement by GGBS is obtained as 40 by weight. Beam-column joints were tested under monotonic loading and behaviour of GGBS concrete (ultimate load, deflection and cracking) is compared with cement concrete. Effect of steel fibres on GGBS concrete by varying the percentage from 0.25 to 1 was also studied. The ultimate load for GGBS and steel-fibre-reinforced GGBS beam-column joint was obtained as 17 and 33% more than that of cement concrete beam- column joint. The experimental studies were compared with numerical method (ANSYS), and good agreements in the results are observed.