Keywords |
내화성능; 고강도 콘크리트; 고온; 열거동; 압축강도; fire performance; high-strength concrete; high temperature; thermal behavior; compressive strength |
Abstract |
A review is presented of experimental studies on the strength performance of concrete exposed at short-term and rapid heating as in a fire and after cooling. Emphasis is placed on concretes with high original compressive strengths, that is, high-strength concrete(HSC). The compressive strength-temperature relationships from the reviewed test programs are distinguished by the test methods used in obtaining the data(unstressed, unstressed residual strength, and stressed tests) and by the aggregate types(normal or lightweight), The compressive strength properties of HSC vary differently with temperature than those of NSC. HSC have higher rates of strength loss than lower strength concrete in the temperature range of between 20℃ to about 400℃. These difference become less significant at temperatures above 400℃ compressive strengths of HSC at 800℃ decrease to about 30 % of the original room temperature strength. A comparison of lest results with current code provisions on the effects of elevated temperatures on concrete compressive strength and elastic modulus shows that the CEN Eurocodes and the CEB provisions are unconservative.
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