Mechanical Properties of Concrete depending on Cooling Conditions After High Temperature Heating

• Published in: Journal of Advanced Concrete Technology Vol. 12; no. 3; pp. 82 - 90
• Main Authors: Kim, Gyu Yong, Choe, Gyeong Choel, Kang, Yeon Woo, Lee, Tae Gyu
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Concrete Institute 27.03.2014; Japan Science and Technology Agency
• ISSN: 1346-8014; 1347-3913
• DOI: 10.3151/jact.12.82

Since the 1960’s, various studies have been carried out on the internal and external factors that might affect heated con-crete in terms of compressive strength, elastic modulus and thermal stress. In particular, thermal properties of aggregate and cooling methods are known to have a significant influence on concrete residual mechanical properties. This study aims to assess concrete mechanical properties based on the types of aggregate and cooling methods used. The used coarse aggregate in concrete was granite, ash-clay and clay type. The circular concrete specimens of Ø100×200mm used in the experiment were heated to the target temperature to test the mechanical properties at a high temperature, slow cooling (room temperature) and water cooling (quenching) conditions. In conclusion, the research finding reveals that the smaller the thermal expansion of the aggregate, the higher the strain at a high temperature while the more dete-riorated the mechanical characters. In addition, the lightweight aggregate concrete was greatly affected by the cooling velocity although the thermal expansion strain of aggregates as the thermal expansion of aggregates took place to a smaller extent, the strength at high temperature remained, while the mechanical properties deteriorated with cooling accelerated. In addition, light-weight aggregate concrete which ash-clay and clay aggregates is greatly affected by the cooling velocity depending on aggregate although the thermal expansion strain of the aggregates was shown to be within a similar range.