Effects of strain rates on mechanical properties of limestone under high temperature

Abstract

The experimental tests for limestone specimens at 700 °C in uniaxial compression were carried out to investigate the mechanical effects of loading rates on limestone by using a MTS810 rock mechanics servo-controlled testing system considering the loading rate as a variable. The mechanical properties of limestone such as the stress–strain curve, variable characteristics of peak strength and the modulus of elasticity of limestone were studied under the strain rates ranging from 1.1 × 10⁻⁵ to 1.1 × 10⁻¹ s⁻¹. (1) Sharp decreases were shown for the peak strength and elastic modulus of limestone from 1.1 × 10⁻⁵ to 1.1 × 10⁻⁴ s⁻¹ at 700 °C as well as a downward trend was shown from 1.1 × 10⁻⁴ to 1.1 × 10⁻¹ s⁻¹ with the rise of the strain rate. (2) The peak strain increased from 1.1 × 10⁻⁵ to 1.1 × 10⁻⁴ s⁻¹, however, there was no obvious changes shown for the peak strain of limestone from 1.1 × 10⁻⁴ to 1.1 × 10⁻¹ s⁻¹. These results can provide valuable references for the rock blasting effect and design of mine.