A numerical study on the tensile splitting of concrete with digital image processing

Abstract

Numerical simulations are performed to investigate the mechanical behavior of concrete in uniaxial compression test and tensile splitting test. Especially, the digital image processing (DIP) techniques are utilized to differentiate the interface types on the fracture surface of the specimen that is already split, which involves transforming the color image of the fracture surface into a binary image through graying, binarization, and opening operation processing. The boundary data obtained from the binary image is further processed by mirrored comparison and contour simplification, and is finally imported into the numerical model to reconstruct the different interface regions on the splitting surface. Different material properties are assigned to the corresponding interface regions through intensive programming with Python, whereby the influence of heterogeneity on the splitting process is analyzed through the established numerical model. Through comparison with homogeneous model, it is found that the heterogeneous model is capable of reproducing a more genuine fracturing process, with respect to the fracture initiation locations and splitting sequence of different interfaces. The proposed modeling schemes are valuable for potential researches exploring the failure process of the materials such as concretes and rocks whose mechanical behavior is influenced by their inherent heterogeneity.

Keywords

• Concrete
• Tensile splitting test
• Digital image processing
• Interface
• Heterogeneous model