Abstract
Mold-cast pore-free concrete (PFC) with a high compressive strength up to 400 N/mm2 has been recently developed and improved by mixing fibers to increase tensile resistance. Steel fibers, stainless-steel fibers and poly-p-phenylenebenzobisoxazole (PBO) fiber bundles were chosen to ensure a sufficient corrosion resistance in the marine environment, and PFC panels reinforced with these fibrous materials were adopted for repairing a coast retaining wall in Hokkaido severely damaged by erosion.
The aim of this study was to evaluate PFC reinforced with different fibers in comparison with ultra-high strength steel fiber reinforced concrete (UFC) in physical properties, i.e. compressive strength, flexural strength and abrasion resistance, as well as chloride ion penetration depth.
The results showed that the steel fiber reinforced PFC had the highest compressive strength of about 330～360 N/mm2, and its flexural strength and abrasion resistance were also significantly higher than those of UFC. The PFC reinforced with stainless-steel fibers or PBO fiber bundles also showed higher values in compressive strength and abrasion resistance than those of UFC, exhibiting higher resistance to erosion by sea waves. In addition, chloride ion penetration depth was similar between PFC and UFC after one year of immersion in seawater.
