Stress-Strain Relations of High-Strength Concrete under Triaxial Compression

Abstract

Three types of stress-strain relations of high-strength concrete under triaxial compression, axial stress–axial and lateral strain, octahedral normal stress–volume change, and octahedral shear stress-strain curves, are studied in this paper. The influence of different load paths is also addressed. The Saenz equation is found to be appropriate to represent the octahedral shear stress-strain relation of high-strength concrete under low confining pressures. A relation between peak octahedral shear stress and peak octahedral shear strain is developed, which can be used to define the peak point on the curve from the peak stresses obtained from the stress failure surface. The high-strength concrete is found to experience degradation in elastic and shear modulus in cyclic loading under triaxial compression.