earticle

영어

This study investigates influence of grain shape of crushed sand, of which particle shape is fixed artificially on concrete properties.
The test results could be drawn as follows. For the fresh concrete properties, as the grain shape become more round, the fluidity of concrete increased due to reduction of internal friction caused by round shape of crushed sand, regardless of W/C ratio. Bleeding increased at early age, but the final amount of bleeding exhibited less than 0.05cm3/cm2, which was negligible regardless of W/C ratio. In addition, setting time was slightly accelerated. For the hardened concrete properties, compressive strength decreased as the grain shape become more round, while W/C 30% of tensile strength increased, and W/C 40% of it decreased. Lastly, the tensile strength of W/C 50% exhibited similar tendency. For freezing-thawing properties, relativity dynamic modulus of elasticity, which is an evaluation index of extensibility frost damage, and weight loss, which an index of scale frost damage, has no significant difference, while accelerating neutralization depth also showed similar result.