This study identified materials and dynamic characteristics of reclaimed aggregates affecting reinforced concrete through materials and supplementary tests to use broken red bricks and waste concrete as substitutes of concrete and obtained the following results.
1) As a result of the compressive strength test, it was found that RBA 30% specimen showed strength of 98.7% and RCA 30% specimen showed 93.85 at 28th day of age which was similar to that of normal concrete. RBA and RCA 60% specimen had somewhat differences compared to normal concrete.
2) Compared with compressive strength manifestation at the 28th day of age, RBA specimen showed the strongest at the 14th days of age, 87~94% while RCA specimen showed the strongest at the 7th day of age, 84~91%.
3) As a result of the tensile strength test, it was found that RBA and RCA 30% specimen had similar tensile strength to normal concrete while RBA and RCA 60% specimen had somewhat different strength compared with normal concrete. It is believed that the reclaimed aggregate manifested tensile strength about within the range of 1/10 of the compressive strength like normal concrete.
4) As a result of the compressive strength test after the fire resistance test, it was found that decrease rate of the strength of the specimen in which normal concrete, RBA and RCA were mixed was 8~10% when it was heated at 200℃. However, in the test after it was heated at 400℃ and 600℃, as more mixed reclaimed concrete was used, the strength decreased to 3.7~4.2%.
5) As a result of the bending specimen test according to types of reclaimed aggregates, it was found that when normal concrete was compared with reclaimed concrete, RBA 30% specimen showed 99~104% of yield load and RCA 30% specimen showed 102~104% of yield load, which were the yield load and the largest yield load of normal concrete. Therefore, it is believed that RBA 30% and RCA 30% specimens has almost similar bending strength to ormal concrete.
6) For the ductile coefficient of bending specimen according to different types of reclaimed aggregates, it was found that RBA 30% specimen showed 8% of ductile strength, RBA 60% specimen showed 11%, RCA 30% specimen showed 8%, and RCA 60% specimen showed 30%, which was lower than that of normal concrete.
7) To sum up the results of material and supplementary tests, the mixed aggregates showed almost the same compressive strength and bending strength compared to that of normal concrete when 30% of broken red bricks and waste concrete were mixed. So this study suggests that they can be applied as thick aggregates.