Evaluation of residual mechanical properties of concrete after exposure to high temperatures using impact resonance method

• Published in: Construction & building materials Vol. 129; pp. 89 - 97
• Main Authors: Park, Sun-Jong, Yim, Hong Jae
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 30.12.2016; Elsevier B.V
• Subjects: Analysis; Compressive strength; Concrete; Dynamic elastic modulus; Fire-damaged concrete; Impact resonance method; Mechanical properties; Strength of materials; Tensile strength; Thermal properties; South Korea; Fire-damaged concrete; Compressive strength; Dynamic elastic modulus; Tensile strength; Impact resonance method
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2016.10.116

•Measurement of dynamic elastic modulus is proposed to increase accuracy of measurement on concrete sample.•Degraded dynamic elastic modulus is not recovered in air re-curing condition.•Estimating equations for tensile and compressive strengths are proposed based on measurement of dynamic modulus. After exposure to high temperature, concrete suffers degradation of its mechanical properties, such as its mechanical strength and elastic modulus, and these residual properties must be evaluated using various destructive and nondestructive methods in order to determine the durability of concrete structures. This study aims to investigate the change in the dynamic elastic modulus of concrete after exposure to high temperature depending on various experimental conditions including mixture proportions, exposure temperatures, post-fire storing period, and post-fire curing regimes. For this purpose, an improved impact resonance method is proposed for measuring the identical resonance frequency of the sample and for evaluating the dynamic elastic modulus, and an experimental study is performed on a total of 350 concrete samples. Accordingly, the estimating equations were obtained in order to evaluate the tensile and compressive strengths of the concrete samples based on a correlation analysis with the measured dynamic elastic modulus.