Review of Mechanical Properties of HSC at Elevated Temperature

TLDR

High‑strength concretes (HSCs) are the focus of this review. The study compiles experimental data on concrete mechanical properties under rapid heating and compares these results with existing code provisions. Test data were categorized by test method and aggregate type and compared to identify behavioral differences. HSCs exhibit greater mechanical property changes than normal‑strength concrete up to ~450 °C, with differences narrowing above that temperature; Eurocode and CEB provisions are more suitable for normal‑strength concrete and unsafe for HSC, and experimental data for lightweight HSC and preloaded HSC are lacking.

Abstract

A compilation of experimental results on the mechanical properties of concrete when exposed to rapid heating as in a fire are presented. Emphasis is placed on concretes with high original compressive strengths, that is, high-strength concretes (HSCs). The compiled test data were categorized by the test methods and the types of aggregate used and compared for behavioral differences. The comparison revealed distinct difference in mechanical properties of HSC and normal-strength concrete (NSC) in the range between room temperature and approximately 450°C. The differences narrowed at temperature above 450°C. Also presented is a comparison of these test results with existing code provisions on the effects of elevated temperature on concrete strength. It is shown that the Eurocode provisions and the Comités Euro-International Du Beton (CEB) design curves are more applicable to NSC than to HSC. In fact, these provisions are unsafe when compared with HSC test results. The study showed a lack of experimental data for lightweight HSC and HSC heated under a constant preload to simulate the stress conditions in HSC columns.