Cement Type Effect on Early Age Crack Behavior of End-to-End Restraind Reinforced Concrete Beam

Abstract This study investigates the early-age cracking behavior of continuously reinforced concrete beams restrained at their ends. It focuses on casting a 30m-long reinforced beam, utilizing concrete mixes with identical compressive strengths but different cement types. Recent research has overlooked how ambient temperature and internal temperature variations from cement hydration affect crack formation in outdoor environments during the early stages. Consequently, it compares the heat evolution during the early stages for the 30-meter beam against that of a 150mm cube specimen, examining the effects of the two types of cement employed. Test results demonstrate that using sulfate-resisting cement (SRC) results in a more significant occurrence of early-age cracks comparing ordinary Portland cement (OPC), with crack widths 33% to 50% wider for SRC. Additionally, the peak temperature resulting from the cement hydration in the cube specimens was 5 to 6 degrees higher than in the 30 m long beam for both cements. Lastly, Since the fineness of SRC is higher than that of OPC, its compressive strength at 7 days was 8% greater than that of OPC; however, the 28-day strengths were nearly the same.