Abstract: The pore structure of concrete exert critical impact on its mechanical properties. In this work, we aimed to describe the correspondence between the compressive strength and the pore structure of concrete. Concrete specimens undergoing standard curing in water for 12 months were dried at diverse temperatures (40 ℃, 105 ℃, 150 ℃, 200 ℃ and 250 ℃) until their weight maintained unchanged. Then, the effects of temperature on concrete pore structure and compressive strength were investigated. Compressive strength tests were carried out to characterize the mechanical properties of the concrete specimens. The pore structure were quantitatively characterized by mercury intrusion porosimetry (MIP) and N2 adsorption. The results implied that the temperature rise leaded to the ever-increasing porosity and gradual damage of the pore structure, while the compressive strength of concrete specimen declined as the temperature rose. The relationship between compressive strength and porosity is in good accordance with the strength-porosity Logarithmic relation proposed by Schiller, showing a correlation coefficient as high as 0.994. It can be concluded that Schiller function is capable of describing the variation of compressive strength under elevated temperature quantitatively.
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