contemporary architecture, especially in facilities such as shopping malls, educational institutions, auditoriums, exhibition centers, airports, and sports complexes where column-free spaces are essential. In such applications, the selection of an appropriate structural system is governed by factors like structural efficiency, optimal material utilization, and overall cost-effectiveness.

This study provides a comparative evaluation of Steel Space Grid systems and RCC Post-Tensioned (PT) systems for large-span applications, emphasizing their structural behavior, efficiency, and practical suitability. Space frame systems, which function as three-dimensional truss configurations, offer high stiffness, efficient load transfer, and significant architectural flexibility; however, they often require intricate joint detailing and involve higher fabrication and erection costs. In contrast, post-tensioned structures employ prestressing tendons to effectively limit deflection and control cracking, thereby reducing self-weight and allowing for more slender structural members, leading to improved material efficiency. The comparative assessment is conducted based on parameters such as span capability, structural performance, construction methodology, economic feasibility, and serviceability criteria. The results indicate that space frame systems are more suitable where architectural adaptability and uniform load distribution are priorities, while PT systems prove to be more economical and efficient for larger spans with better deflection control. Overall, the study underscores the importance of selecting structural systems based on span requirements to achieve optimal performance and cost efficiency in large-span construction projects.