High Strength Concrete Tests under Elevated Temperature

Abstract

In recent years, application of high strength concrete (HSC) has attracted increasing interest in the construction industry due to its significant economic, architectural, and structural advantages, compared to the conventional normal strength concrete (NSC). However, under fire condition, which is one of the most common hazards that attack building structures, HSC members may be subjected to explosive spalling. Strength reduction of structural members may occur, leading to severe consequences such as failure of members or even collapse of the whole structure. A newly designed 2- layered cylindrical specimen consisting of an HSC core and an NSC outer layer is proposed to improve the fire performance of HSC members under elevated temperature. The NSC layer is designed to act as an outer layer insulation to reduce the thermal gradient and also serve as a lateral confinement to prevent the HSC core from spalling. Compression and thermal tests were performed on the specimens to investigate their strength and behavior under elevated temperature. Test results preliminarily verify the feasibility of 2-layered design and at the same time provide insights for the applicability of 2-layered columns in practical construction projects.