Abstract
Hiroshima prefecture is famous for a producing district of oyster in Japan. While the production of oyster in Hiroshima prefecture was about 60％ in Japan, oyster shell of about 100,000t was produced as a by-product. At this time, oyster shell has utilized as a fertilizer and a feed, but the amount of utilization of oyster shell has not been great. Oyster shell porous concrete（Oy-PoC）have been investigated for further utilization of oyster shell. Oyster shell is used as aggregate of Oy-PoC. Oyster shell aggregate is produced by crushing and sieving oyster shell. In this study, we investigated the effects of aggregate orientation and water cement ratio on basic properties of Oy-PoC. The vertical and horizontal cylinder moulds were used for turning oyster shell aggregate orientation. Oyster shell aggregate orientation had no effect on the compressive strength of Oy-PoC. The coefficient of permeability of horizontal type Oy-PoC was twice as large as the one of vertical type. Porous concrete with crushed stone generally fractures from cement paste. Oy-PoC fractured from oyster shell aggregate because of the low aggregate strength. The compressive strength of Oy-PoC didn’t develop by decreasing water cement ratio. Therefore, the compressive strength of Oy-PoC was independent of the cement paste strength.
