Mechanical Properties of Concrete in Compression Exposed to Sulfuric Acid

摘要

This paper presents the degradation of compressive strength and stiffness of concrete after immersed in 2,5 % sulfuric acid solution. The durations of immersion are 0, 3, 7, 14, and 28 days. After the immersion, ultrasonic pulse velocity and compression tests are performed on the specimens. The relative dynamic elastic modulus, compressive strength and its initial stiffness decrease with increasing the duration of immersion, as a result of the increasing microcracks in the concrete. The strain at peak stress increases with increasing the duration of immersion. The degradation of compressive strength, the degradation of initial stiffness and the value of strain at peak stress of damaged concrete are formulated as a function of relative dynamic elastic modulus. A simple mathematical expression for stress-strain relationship of concrete damaged by sulfuric acid is proposed and stress-strain curves at different level of damage are compared.