earticle

영어

This experimental study was performed to investigate the mechanical characteristics of surface treated coarse aggregates and concrete using them, And, the applicability was confirmed and increasing effect in compressive strength was evaluated. Here, Surface treating is to remove the mortar paste bonded on the surface of recycled coarse aggregates and the grade of surface treatment which is the principal test variable is the number of drum rotation in Los-Angeles abrasion test. Test result showed the increase of about 30% in compressive strength was developed when recycled coarse aggregates treated with 300 rotations were used in the concrete. However, there was no increase in the concrete using recycled coarse aggregate treated with more than 300 rotations. Considering the limit of increase in compressive strength and the cost effectiveness in surface treating, the grade of surface treating with 300 rotations was the optimized one. The characteristics of recycled coarse aggregate, density, absorption, and unit weigh, was linearly improved with the increase of the grade of surface treatment. Loss in weigh in abrasion test showed high rate in increase in the range of 100 rotations and low rate in the range of more than 100 rotations. The slump in the concrete with recycled coarse aggregate linearly increase with the increase of the grade of surface treatment.