DYNAMIC MULTIAXIAL STRENGTH CRITERION FOR CONCRETE DEVELOPED BASED ON THE S CRITEIRON

The classical strength criteria including Mohr-Coulomb strength theory, Drucker-Prager strength theory, Matsuoka-Nakai strength theory, Lade-Duncan strength criterion and Hoek-Brown strength criterion are developed into dynamic multiaxial strength criteria by deriving the strain-rate-dependent strength parameters of each static strength criterion. The strain-rate-dependent strength parameters are obtained by combing the dynamic uniaxial S criterion and the basic strength indexes of concrete material. Then the change rules and value range of strength parameters of five strength criteria are analyzed by these statistical material parameters of S criterion. On the basis of the uniaxial compressive and tensile strengths of concrete, the strength curves of each dynamic multiaxial strength criterion at plane stress condition, meridian plane, deviatoric plane and the strength surfaces in the principle stress space are given. Then the di erences of the five dynamic multiaxial strength criteria are analyzed. The five dynamic strength criteria are evaluated by the dynamic biaxial and true triaxial strength tests. The dynamic Drucker-Prager criterion shows big di erences with the dynamic test results of concrete. All of the dynamic strength criteria are able to reasonably describe the strength rules under biaxial compression-tension. It also shows big di erence among these dynamic strength criteria, while the dynamic Matsuoka-Nakai criteria describes the strength rules better than others. Under dynamic true triaxial proportional loading, Mohr-Coulomb and Hoek-Brown strength criteria cannot consider the influences of intermediate principal stress, while the Matsuoka-Nakai and Lade-Duncan strength criteria are capable of well describing the test results of concrete.