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Composite slab/flooring system known as fast track construction with profiled steel deck and regular concrete topping is very popular. This paper presents the development and performance evaluation of a new high performance composite flooring system incorporating emerging green cost-effective Engineered Cementitious Composites (ECCs). The high strain capacity while maintaining low crack widths makes fiber reinforced an ideal durable material for the composite floor construction. The proposed ECC based composite floors can resolve the problems associated with regular concrete based composite floors. Experimental investigations as per current Standard Specifications accompanied by Code based theoretical investigations were conducted to evaluate the structural performance of such flooring system in the construction and service stages. Thirty full-scale composite slabs were fabricated and tested under simply supported four-point loading conditions. The variables in the tests included: two types of concrete (a green cost-effective ECC and a commercial self-consolidating concrete ‘SCC’), two types of profiled steel sheet/deck, five different shear span and presence/absence of stud shear connectors. The structural performance of ECC based composite slabs was compared with their SCC counterparts based on load-displacement response, shear load resistance, failure modes, strain development in concrete/steel, load-slip behaviour, ductility, energy absorbing capacity and steel-concrete shear bond resistance. ECC composite slabs have shown superior performance compared with their SCC counterparts in terms of strength, ductility, energy absorbing capacity and shear bond resistance.

The interfacial reaction between the Al matrix and the Al 62.5 Cu 25 Fe 12.5 quasicrystalline (QC) reinforcing particles to form the Al 7 Cu 2 Fe ω-phase has been used to further enhance the strength of the Al/QC composites. The QC-to-ω phase transformation during heating was studied by in situ X-ray diffraction using a high-energy monochromatic synchrotron beam, which permits to follow the structural evolution and to correlate it with the mechanical properties of the composites. The mechanical behavior of these transformation-strengthened composites is remarkably improved as the QC-to-ω phase transformation progresses: the yield strength increases from 195 MPa for the starting material reinforced exclusively with QC particles to 400 MPa for the material where the QC-to-ω reaction is complete. The reduction of the matrix ligament size resulting from the increased volume fraction of the reinforcing phase during the transformation can account for most of the observed improvement in strength, whereas the additional strengthening can be ascribed to the possible presence of nanosized ω-phase particles as well as to the improved interfacial bonding between matrix and particles caused by the compressive stresses arising in the matrix.