Failure process 8v=8a+2 al fe 10 Minimum-volume level Transverse strain (Et) Volumetric strain (E) 05 Axial strain (Fa) f=cylinder strength -4 -3 -2 -1 2 3 4 Strain:mm/m The rapid expansion at the minimum volume level,where the tensile strain at right angles (to the direction of maximum compressive stress soon exceeds the magnitude of the compressive strain is a failure feature of both uniaxial(单轴)and more general triaxial(三向)compressive behavior Concrete in the "critical'zones of compression always failed by “splitting”(劈裂)--never by“crashing”( 压碎)（压碎） The rapid expansion at the minimum volume level, where the tensile strain at right angles（正交） to the direction of maximum compressive stress soon exceeds the magnitude of the compressive strain is a failure feature of both uniaxial （单轴）and more general triaxial （三向）compressive behavior v a t     2