Flexural performance of ultra-high performance concrete beams produced with granite manufactured sand

Manufactured sand (MS) has different characteristics to natural sand (NS), particularly in terms of morphology and size distribution. The flexural behavior of concrete beams reinforced with MS presents a critical challenge when using MS in engineering practice. In the present study, granite manufactured sand (GMS) was used as alternatives for NS. Six ultra-high performance concrete (UHPC) beams with varying GMS contents were subjected to flexural performance testing. The failure mode of UHPC beams with GMS (GMS-UHPC beams) was similar to that of UHPC beams with NS (NS-UHPC beams). The workability of MS-UHPC exhibited an increase initially, followed by a decrease as the increasing GMS content. The test results indicated that a valley was observed in the flexural performance of UHPC beams with different GMS contents. The response of all test beams could be categorized into three distinct stages. Compared to the NS-UHPC beam, the GMS-UHPC beams exhibited a greater occurrence of secondary cracks and a more evenly distributed crack pattern. A suitable equation was proposed to calculate the ultimate bearing capacity of UHPC flexural members with different GMS contents, and the calculated and test values matched well.