ECC를 활용한 고강도콘크리트 기둥의 폭렬 저감 방안에 대한 실험적 연구

Abstract

High-strength concrete(HSC) must be designed to protect under the fire because the concrete structure sometimes exposed to very high temperature. Such fire temperature may cause explosive spalling of HSC members. An explosive spalling is defined as the damages of concrete exposed to high temperature during the fire by causing cracks and localized bursting of small pieces of concrete, and reported that is caused by the vapor pressure and thermal stress. The purpose of this study is to obtain the explosive spalling reduction method of HSC members using fire resistance-engineered cementitious composites(FR-ECC) under fire temperature. The present study conducted the experiment to simulate fire temperature by employing of FR-ECC and investigated experimentally the explosion and cracks in heated surfaces of these members. Employed temperature curve were ISO 834 criterion(3hr), which are severe in various criterion of fire temperature in concrete buildings. In results, the ratio of unstressed residual strength of HSC columns increases and explosive spalling degree decrease by FR-ECC cover. And the FR-ECC spalling reduction methods(cover thk. 30 to 50mm) shows the better fire resistance performance in HSC members.