Marble is a fundamental material in world’s built cultural heritage. However, often affected by environmental influences, it is subjected to compositional, chemical, and structural degradation over time. The restoration of marble elements is thus an essential process for preserving the built heritage; yet the long-term structural performance and durability of rehabilitated marble components remain insufficiently studied and understood. This study investigates the mechanical behaviour of two marble types, in pre- and post-restoration, with a particular focus on three different notch configurations and the complex marble/adhesive interfaces under applied loads. Through a systematic analysis combining experimental and numerical methodologies, this research aims to unveil the principles governing collapse in restored marble structures. The findings provide key insights into the structural integrity of restored elements, contributing to the optimization of conservation techniques and the development of more durable restoration strategies.