Load-resistance features of an innovative concrete panel-steel beam modular arch system

This study proposed a modular arch system that allows lean construction, considering the load-resistant features of the underground arch. In this proposed arch system, H-shaped steel frames and precast concrete panels are combined in a noncomposite state, giving them respective resistance roles to bending moment and compression force. Experimental and numerical approaches were conducted to investigate its load-resistant response and load transfer mechanism, focusing on strain, stress distribution, and deformation under load. The laboratory test revealed that the flexural strain of the concrete panel was negligible, and the strain distributions of the two members at the same cross-section were different, demonstrating the feasibility of this non-composite arch. Finite element analysis under various load conditions, including the arch's operation stage, revealed that even under high moments, the arch maintained its intended non-composite behavior with minimal stress and strain, indicating a high level of safety. Therefore, these results confirm that this arch enables efficient cross-sectional design by combining materials strong in bending and compression and assigning them independent roles. Additionally, based on the noncomposite behavior of this arch system, a theoretical design approach and a simplified analysis model for safety evaluation are proposed, along with guidelines for its practical design and analysis.