Papers by Keyword: Impacting Crushed Aggregate

Abstract: Porous concretes with continuous voids have been gaining more interest as an ecological material because of their useful functions such as water permeability and adsorption ability. Especially, to make porous concrete much more environmentalized, micropores play a role of nest for microorganism and germs to live in. So micropore distribution and the size of micropores especially open pores are the key point . In this study, the size and distribution of micropores of porous concrete were effected by the AE agents to the cement pastes and then by the treating types, treating times, treating temperatures, and the vacuum pressure during the treating. And another group specimens were added sodium bicarbonate and alum. And then physical properties were examined, digital microscope was also used to observe the micropores sizes and distributions. Cracks were observed on the cement-aggregate joint when the amount and vacuum pressure increased. And high treating temperature shows no good on the bonding of cement paste and aggregate.

Abstract: Porous concretes with continuous voids have been gaining more interest as an ecological material because of their useful functions such as water permeability and adsorption ability. So pore size distribution and the shape of especially open pores are the key point to permeability. In this study, the size and shape of pores of water permeable concrete were primary controlled by the size and shape of aggregates and secondly by the expanding agents to the cement pastes. 2 types of raw coase aggregate, type I and type C which mean fabricated by impact crusher and concrusher, were taken into uses and 3 sizes of aggregate were used, namely 3 to 5mm, 5 to 13 mm, and 13 to 20 mm. The compressive strength was found to be higher when using impact crushed aggregate. And the smaller size of aggregate was used, the higher compressive strength was achieved.