The traditional precast T-beam faces issues such as excessive diaphragms，difficult formwork installation and removal，and low levels of intelligence in intelligent bridge construction.To address these issues，this paper focused on the optimization of the number of diaphragms and the application of prefabricated diaphragms.By analyzing different diaphragm configuration schemes and comparing the contributions of prefabricated diaphragms and precast diaphragms to the lateral stiffness of the bridge，this paper deeply explored the impact of diaphragms on bridge performance.The research results indicate that the T-beam system with fewer diaphragms is feasible in intelligent construction，but the system without diaphragms places higher demands on the performance of bridge decks.Additionally，compared to precast diaphragms，prefabricated diaphragms contribute less to the lateral stiffness of the bridge，and their use increases the stress on bridge decks.Furthermore，the installation position of diaphragms has a significant impact on the lateral stiffness of the bridge.