Influence of aspect ratio on flexural behavior of reinforced self-compacting concrete beams

Concrete is a quasi-brittle material whose basic mechanical properties are size-dependent. Due to simple substitution in profoundly congested support structures without experiencing any consolidation, non-segregation property, and smooth finishing, it could be an exceptionally great choice in the concrete industry. The research object is the size effect on the flexural behavior of reinforced self-compacting concrete (SCC) beams by varying depth, length, and span. The length to depth ratio (aspect ratio) was 3.88, 5.38, 8.75, 11.5, and 15.38. SCC trial mixes were tech-nologically advanced using FA (FA) as filler material and conplast SP430 as Super-plasticizer (SP). The workability properties were determined via the T50 cm slump flow, slump flow, U-box, V -funnel, J-ring, and L-box tests. FA (30%) with SP (1.9%) is satisfied with all the requirements of SCC as per EFNARC guidelines, and the designed compressive strength of concrete was obtained as 30 MPa. A total of six beams with various sizes, such as depths of 100 mm, 150 mm, and 200 mm, and lengths of 900, 1700, and 2200 mm, were cast with 1.2% tensile reinforcement bars. Based on the depth effect of beams, the load-deflection behavior, flexural strength, ductility index, and stiffness were studied. It is revealed that there is a decrease in strength properties by increasing the depth of beams during the static load conditions. Beams with a length equal to 1700 mm reached the best performance. It was also found the most advantageous l/d proportion, in terms of mechanical performance, is equal to 5.38.