Study on Elastic-plastic Damage Model and Size Effect of Concrete Based on Fracture Energy
To study the fracture characteristics and size effect of concrete,this study employs fracture energy and e-quivalent strain to express damage evolution law.By incorporating the plastic deformation characteristics of concrete,an elastic-plastic constitutive model for damage based on fracture energy was proposed,and the corresponding finite element numerical calculation model was established.An improved energy size effect formula was introduced to validate the rea-sonability of numerical simulation results.By conducting finite element numerical simulations and sensitivity analyses of parameters on a three-point bending beam,it is found that when the small-size beam fails,the fracture process zone may not expand to the characteristic length,thereby limiting energy dissipation and consequently enhancing fracture resistance and nominal strength of the beam.As the size of beams increases,the FPZ at beam failing gradually approaches the char-acteristic length,resulting in a gradual decrease in nominal strength of the beam.Once the FPZ reaches the characteristic length,there is no further decrease in nominal strength with increasing beam size.
NETL
NSTL
万方数据
维普
