It is important to mix slag fine aggregate in concrete from the viewpoint of benefiticial utilization of industrial by-products and conservation of natural resources. There have been many reports about properties of concrete containing slag fine aggregate. Most of them, however, are investigating the method on how to improve the properties of concrete containing slag fine aggregate as same as those of normal concrete by reducing mixing ratio of slag fine aggregate and/or increasing binder content in concrete. These methods result in increasing of cost and time. Therefore, it is required to apply concrete with high volume slag fine aggregate without quality improvement (HVSA concrete) to appropriate concrete structures. It is concerned that the increased bleeding affects the properties of HVSA concrete. In this study, mechanical properties, durability and workability of HVSA concrete were investigated experimentally.
　As a result, the effect of bleeding on the mechanical properties of HVSA concrete was small when the bleeding content was less than 0.5cm3/cm2 while bleeding of about 1.0cm3/cm2 reduced them. The exposure test in marine environment for 1 year revealed that the durability of HVSA concrete was as same as that of normal concrete. The pumpability of HVSA concrete were as same as those of normal concrete when the mixing ratio of slag fine aggregate was less than 50 %. The HVSA concrete with more than 70% of mixing ratio could be produced by casting with hydraulic hopper. There results implied that unreinforced concrete port structures such as wave-dissipating block can be produced with HVSA concrete when proper casting method was selected.