Preventive Effect on Fire Spalling of High-Strength Concrete With Jute Fibre in Ring-Restraint Specimen

摘要

High-strength concrete (HSC) is widely used to construct high-rise buildings, bridges and other heavy structures in the world. However, the best way to reduce spalling risk of HSC structures when exposed to high temperature, such as fire is still ongoing. According to the researches, thermal stress and vapour pressure are the major factors that cause concrete spalling at high temperatures. In addition, Japan Concrete Institute Technical Committee previously examined the potential performance of concrete in high-temperature conditions (ref. JCI-TC154A), and proposed the ring restrain heating test. As a preventive way to reduce explosive spalling of HSC, commonly Polypropylene (PP) fibres are used. On the other hand, many research shows that, natural Jute fibre are also effective however, only few researches and experimental studies regarding the study of preventive effect of spalling. Therefore, this study aims to confirm the difference of spalling property on various fibre-reinforced high-strength concrete (HSC) using ring-restraint specimen. Jute and PP fibre of 0.1 vol% and the heating condition is a RABT 30 rapid heating curve. The restrained stress and vapour pressure were measured. In result, spalling was observed for HSC and HSC with PP fibre specimen, no spalling was occured HSC with Jute fibre specimen.