Calcium silicate hydrate (C-S-H) is a significant hydration product in cementitious materials which plays a significant role in contributing to cohesive strength and properties of cementitious materials. Despite numerous studies, the failure mechanism of C-S-H gels remains uncovered. In this study, we explored the complex failure mechanisms of C-S-H sheets at different angular configurations. Our research unveils the intricate relationship between these mechanisms and the structural configurations and external loading conditions. Notably, we have observed that C-S-H sheets exhibit enhanced cohesion under specific configurations, while such enhancement is absent in alternative scenarios. This study demonstrates the nuanced behavior of C-S-H sheets under varying loads, underscoring the pivotal role played by angular configurations in shaping their failure mechanisms. These insights not only contribute to the development of coarse-grained molecular models for C-S-H but also provide valuable guidance for further research about the failure mechanism of the cement-based materials.