Peridynamics Method Based on Viscoelastic Deformation Mechanism of Concrete

Abstract:

The governing equation of the original peridynamics is derived from the energy equation of work done by conservative forces， which cannot reasonably reflect the viscoelastic deformation behavior of materials and the energy dissipation of the system. To solve this problem， a peridynamics method considering the work done by non-conservative forces is proposed. The theoretical framework includes two parts： viscoelastic interaction of material points and its motion equation， and rate dependent fracture criterion of bond. In describing the movement of material points， based on the understanding of the deformation mechanism of concrete， the viscoelastic interaction model between material points is proposed. The viscoelastic motion equation is established by using the Hamilton’s principle considering energy dissipation. Using the viscoelastic peridynamics method and the energy density equivalent method of continuum mechanics， the determination methods of elastic parameters and viscous parameters are proposed. In terms of describing bond fracture and material strength， the rate dependent fracture criterion of bond is developed by using the dynamic uniaxial S criterion of concrete. Numerical experiments are conducted to investigate the functions and advantages of the viscoelastic peridynamics method proposed. The results show that the peridynamics method proposed can reasonably reflect the influence of loading rate on the deformation， strength， and cracking behavior of concrete.

Key words:peridynamics;concrete;viscoelastic;strain rate effect;deformation mechanism