Behavior of mass concrete under biaxial compression-tension and triaxial compression-compression-tension

To meet the requirement of nonlinear analysis and design for mass concrete structures, the mechanical characteristics of mass concrete specimens 25 × 25 × 40 cm with three-graded aggregate 5–80 mm under biaxial compression-tension and triaxial compression-compression-tension was studied experimentally with the multiaxial concrete apparatus. In comparison with the corresponding wet-screened concrete specimens 15 × 15 × 30 cm with two-graded aggregate 5–40 mm, it was found that the wet-screened effect and size effect under complex stress states were obvious, as under uniaxial stress state. By regression of the tests results, respective failure criteria for mass concrete in principal stress space and octahedronal stress space were proposed.