With the utilization of higher-strength steel in building structures, more stringent requirements are imposed on the connectivity performance of joints. Superhigh-tension bolts (SHTB), compared to welding and other methods, can form reliable connections through a simple construction process, and significantly reduce material consumption simultaneously. As the key component for load transfer, the failure of the joint can easily lead to local failure of the structure and probably trigger progressive collapse. Bolt fracture is a common and severe joint failure mode. Currently, research on bolt fracture is mainly focused on Grade 10.9 or even lower grades, with limited studies on the increasingly adopted Grade 12.9 and the promising Grade 14.9 bolts. In this study, coupon tests of Grade 14.9 bolts and finite element analyses were conducted with smooth and notched round bars. An evaluation of its fundamental performance was carried out. The comparison results of simulations and experiments showed that the element mesh size has a great impact on the accuracy of critical fracture parameters for key elements, and a mesh size of 0.05 mm is recommended. Critical parameters at fracture were obtained in Abaqus, and the commonly used SMCS fracture models were calibrated, on this basis, the model was subjected to a secondary modification based on damage factors, the model parameters α and β was determined as 8.1304 and 3.7911, respectively. Simulation results indicated that the SMCS model shows good agreement with experimental results.