Peridynamics study of the fracture behavior of concrete under uniaxial compression.

Understanding the fracture behavior of concrete plays a major part in predicting and designing novel high-performance and functional concrete materials. This paper presents a new numerical model based on Peridynamics (PD) for investigating the fracture behavior and mechanical properties of concrete, in terms of the effect of boundary friction, randomness, and slenderness. Meso-structure models of concrete were constructed to perform uniaxial compression tests. The results show that due to the restraint of boundary friction, the peak stress, fracture energy, and peak strain under high friction (HF) boundary condition are higher than that under low friction (LF) case implying that the specimen in the HF case can sustain larger deformation and bear higher stress. In term of fracture pattern, in the LF case, the cracks are free to propagate along the weakest part of the concrete specimen and form vertical cracks paralleled to the compressive loading direction while under the HF boundary condition the frictional restraint in cracks has an impact on the fracture process as the boundary friction can prevent local fracture. The randomness introduced to account for the heterogeneity of concrete material will cause a decrease in strength and an increase in the damage degree of specimens. The slenderness has a strong effect on the mechanical properties of specimens: the stress and fracture energy increase with the decreasing slenderness. The simulated mechanical properties and fracture patterns in this study agree well with experimental results indicating that the application of PD theory in concrete has sufficient accuracy. [ABSTRACT FROM AUTHOR]