Flexural behaviour of self-compacting coconut shell reinforced concrete beam using manufactured sand

This research study examines the structural performance of self-compacting coconut shell concrete (SCCSC) reinforced beams for flexure, emphasising the impact of manufactured sand (M-sand). This study aimed to investigate the effectiveness of M-sand as a substitute for river sand in concrete. The replacement levels of natural river sand with M-sand were set at 25%, 50%, 75%, and 100% in the concrete mix. Six reinforced concrete (RC) beams were constructed and subjected to flexural loading tests to assess their structural behaviour. The assessment included analyzing load-carrying capacity, load-strain relationships, deflection behavior, ductility, crack characteristics and failure modes. The beams were designed as under-reinforced sections. The test outcomes indicated a notable improvement in the load-carrying capacity of self-compacting coconut shell concrete by 22.22% when M-sand was substituted. This enhancement was credited to the synergistic interaction between the coconut shell (CS) and the interlinked system of M-sand within the concrete. Moreover, under serviceability conditions, the deflection and cracking attributes of self-compacting coconut shell concrete using M-sand are on par with those of SCCSC using river sand.