SPH modeling of concrete failure using the M7 microplane model

Modeling concrete failure under extreme events, such as hypervelocity impact, air-blast loading, or water impact, has long been an open research area in the engineering mechanics community. Over the years, numerous concrete constitutive models capturing failure have been developed and effectively applied within traditional computational techniques, such as the finite element method (FEM). However, research activity involving meshfree and particle-based numerical methods, such as smoothed particle hydrodynamics (SPH), remains limited in this context. This paper presents the first implementation of the evolving microplane (M7) concrete constitutive model within the framework of SPH. The meshfree nature of SPH enables the simulation of scenarios involving extreme deformations, material separation, and discrete fractures, challenges that conventional mesh-based computational techniques often struggle to address. Comprehensive mathematical and implementation details are provided, and the framework is verified and validated through several benchmark tests that demonstrate the applicability of the M7 model in SPH. The framework is further applied to a hypervelocity impact scenario, illustrating its capability to capture fracture and fragmentation under extreme conditions. Finally, to support community adoption, the open-source SPH implementation, including calibration procedures and parameters, is made available via a GitHub repository. This work provides the SPH community with a robust tool for modeling concrete failure and contributes to advancing computational methods for extreme events simulations.