The selection of a constitutive model for plain concrete largely depends on the specific applications and loading conditions it will be subjected to. However, the Concrete Damage Plasticity (CDP) model is frequently regarded as one of the best representative constitutive models for plain concrete due to its ability to accurately simulate the non-linear behavior of concrete under various loading conditions, including tension, compression, and shear. The CDP model operates by incorporating both plasticity and damage mechanics, which allows it to simulate the complex behavior of concrete, including irreversible deformation (plasticity) and degradation phenomena (damage) (Lubliner et al., 1989). This dual approach is highly effective in capturing the cyclic loading effects and post-cracking behavior, which are critical in many structural applications. The model is versatile and can be used in diverse analyses, such as seismic response, impact analysis, and durability studies, making it highly practical for real-world applications (Grassl & Jirásek, 2006). This model allows for the calibration of various parameters that govern the evolution of damage and plasticity, thereby enabling tailored simulations that account for different concrete characteristics (Lee & Fenves, 1998). Its effectiveness is well-documented in finite element software applications where it is utilized to predict the performance of concrete structures (Jankowiak & Lodygowski, 2005). Consequently, due to the combination of its theoretical robustness and practical applicability, the CDP model is widely adopted in both research and industry settings for simulating the behavior of plain concrete. References Grassl, P., & Jirásek, M. (2006). Damage-plastic model for concrete failure. *International Journal of Solids and Structures, 43*(22-23), 7166-7196. Jankowiak, T., & Lodygowski, T. (2005). Identification of parameters of concrete damage plasticity constitutive model. *Foundations of Civil and Environmental Engineering, 6*(1), 53-69. Lee, J., & Fenves, G. L. (1998). Plastic-damage model for cyclic loading of concrete structures. *Journal of Engineering Mechanics, 124*(8), 892-900. Lubliner, J., Oliver, J., Oller, S., & Onate, E. (1989). A plastic-damage model for concrete. *International Journal of Solids and Structures, 25*(3), 299-326.