Coupled Modeling of Hydromechanical Behavior of Saturated Concrete Under High Stresses and Dynamic Loading: Influence of Pore Pressure

This paper investigates the dynamic response of water-saturated concrete under high stress levels, with a particular emphasis on the role of pore pressure. An enhanced elastoplastic damage model, incorporating dual plastic mechanisms, is proposed to capture the coupled hydromechanical behavior of concrete under combined high stress and high strain rate loading. Key improvements include the refinement of the porosity-volumetric strain relationship, the incorporation of full hydromechanical coupling under dynamic loading, and the integration of strain rate sensitivity into the pore collapse mechanism and material strength. The improved constitutive model and numerical methodology are validated through simulations of uniaxial tensile tests and three sets of compression tests. Parametric studies are conducted to explore the influence of pore pressure on the confined response of concrete under both static and dynamic loading conditions. The results demonstrate that interstitial pore pressure significantly affects both the volumetric and deviatoric behaviors of saturated concrete, with its influence becoming more pronounced under dynamic loading. The findings provide valuable insights into the hydromechanical behavior of concrete structures subjected to extreme loading scenarios.