Experimental and numerical analysis of self-compacting geopolymer concrete composite slab

Composite slab systems have earned high regard in the building industry as a fast-track construction and an economical approach. Geopolymer concrete has been recognised as an environmentally friendly material that produces lower CO2 emissions than conventional cement-based concrete. This paper compares the structural and shear bond performance of a composite slab incorporating self-compacting geopolymer concrete (SCGC) to that of a normal concrete (NC) composite slab. This research also focuses on the structural performance of SCGC composite slab reinforced with a 2 % basalt fibres (BFs) dosage. BFs have been acknowledged for their sustainable feature and outstanding mechanical properties, making them a feasible choice compared to their counterparts. This study examined full-scale composite slabs made of NC, SCGC and self-compacted geopolymer concrete reinforced with BFs (SCGCB), with a targeted compressive strength of 32 MPa, subjected to a four-point flexural test. Composite slabs were tested with two different shear spans of 600 mm (long) and 300 mm (short). The performance of composite slabs was assessed in terms of failure modes, load-deflection response, a flexural strain developed at concrete and profiled sheet surfaces, load-slip response, moment capacity, energy-based ductility of a composite slab, and shear bond resistance. SCGC showed an average 7.96 % lower shear bond capacity than the NC composite slab. SCGCB composite slabs exhibited an overall noticeable improvement in load-carrying capacity, strain capacity, ductility and shear bond resistance compared to SCGC composite slabs. A nonlinear finite element model was developed to predict the shear bond capacity of SCGC and SCGCB composite slabs. The developed model was validated against the experimental results, showing good agreement with a variance of less than 10 %