The Effect of Chemical Composition of Quartzite and Limestone Aggregates on Concrete Characteristic Due to ASR

Abstract

Quartzite (QS)  and Limestone (LS)  in the Coastal area of District Pati and Blora have not been utilized optimally as coarse aggregate [1]. Physical of coarse aggregate and chemical composition utilized to obtain the characteristic of quartzite and limestone concrete. A total of 26 (twenty-six) cylindrical concrete specimens with a coarse aggregate ratio of quartzite 70%:30% limestone under two curing conditions were prepared. 18 specimens were submerged in water at 20°C and the rest for 80°C ASR environmental conditions. Compressive strength test, split tensile strength test, and modulus elasticity test of concrete were carried out. The CaO and SiO₂ of coarse aggregate and their correlation to the compressive strength were evaluated. While Lost In Compressive Strength (LICS) test was carried out on 6 specimens in ASR environment. Replacement of 30% QS coarse aggregate with LS showed compressive strengths of 19.69 Mpa and 29.85 Mpa for w/c ratios of 0.61 and 0.47 respectively. There is relatively tenous negative correlation mids the CaO content on the compressive strength and the density of concrete. Concrete with a w/c of 0.47 and 0.61 had compressive strengths of 25.76 Mpa and 20.86 Mpa, respectively, under ASR circumstances. LICS occurred respectively of -4.7% and 13.7% which showed an increase in concrete compressive strength with a w/c ratio of 0.61 and a decrease in concrete compressive strength with a w/c ratio of 0.47 at 28 days of age in an ASR environment. Henceforth, recommends to apply w/c ratio of 0.61 for utilizing QS coarse aggregate in concrete production