<p>Concrete continues to be a fundamental building material in modern construction. Therefore, the repair and rehabilitation of concrete elements are critical for maintaining infrastructure at an optimal performance level. In this regard, cold joints, which result from delays between the placement of old and new concrete, are commonly found at interfaces in Reinforced Concrete (RC) structures. Cold joints in high-importance structures can significantly impact the performance and integrity of concrete elements, especially in critical zones. This study aims to investigate the mechanical properties of cold joints, which typically exhibit reduced strength compared to surrounding materials, thereby raising concerns about their failure under stress concentrations. Drawing upon existing literature, including numerical simulations and experimental testing, this study presents a robust simplified numerical simulation modeling framework for predicting the behavior of cold joints in concrete structures. For this purpose, the proposed framework is implemented to a real case study and develops a numerical model that incorporates different fracture mechanisms. In this line, the paper also discusses the rehabilitation process associated with real under-study foundation. This comprehensive approach contributes to a better understanding of the effects of cold joints on structural integrity, facilitating the development of more effective repair strategies and enhancing predictive capabilities in engineering practice.</p>