Evaluation of Stress Block Parameters for Steel Fibre Reinforced SCC with Recycled Concrete Aggregate
Stress block parameters are predominantly used in the design of concrete structural members and offer a convenient method to arrive at the flexural capacity. The objective is to find the equivalent stress block parameters namely, the effective average concrete ratio and the stress block depth factor for Self Compacting Concrete with recycled aggregate (RSCC) and SCC with recycled aggregate incorporating steel fibres (SFRSCC) SCC is defined as a highly workable concrete which flows by its own weight. Sustainability of SCC can be improved by replacing mineral aggregates by industrial waste like rubber, recycled aggregate, granite powder etc. An experimental investigation was carried out on the stress strain characteristics of SCC by partially replacing 25, 50, 75 and 100 of coarse aggregate by recycled aggregate (RSCC) for varying design strength 30, 40, 50 MPa under monotonically increasing axial loading. The behavior of SCC with 100 recycled aggregate incorporating steel fibres with different volumetric ratios is also explored. A total of 72 cylinders were prepared to develop a stress strain model for RSCC and SFRSCC. The results were compared with the existing models used for SCC and recycled aggregate and it indicates that Saenz model was found applicable for finding the stress block parameters. The proposed parameters were found to be lesser than the values for normal concrete specified by IS 456 and that these parameters could be used to determine the flexural strength of members made using the above composites.