Protective Facility ISSN:3058-7816(Print) 3058-8618(Online) 방호시설

This study investigates the structural behavior of blast-resistant door systems under extreme dynamic blast and rebound loads, proposing optimal design strategies to maximize survivability and safety in practical applications. Through numerical analysis and mechanical mechanism evaluations, the load transfer paths, stiffness contributions of individual components, detailed joint structures, and load response characteristics of the anchor system were comprehensively examined. The results demonstrate that a straight horizontal reinforcement layout for the internal frame effectively mitigates stress concentration and maximizes overall flexural stiffness, and supporting mechanisms should adopt a statically determinate two-point support and symmetric layout for uniform load distribution. In terms of materials, the overall flexural stiffness is dominated by the cross-sectional performance of the steel plates, necessitating the optimization of the thickness distribution between the front and rear plates. Through-anchors were found to contribute primarily to structural integrity by resisting interlayer shear forces rather than suppressing initial deflection. Additionally, the necessity of a stepped design for edge steel plates to prevent shear failure at welds and an embedded direct bearing support structure for the lower roller base was validated. Notably, the rebound load occurring immediately after an explosion in a closed state is extremely concentrated on specific anchors (up to 38.1 %). Eccentricity between the line of action and the anchors exponentially amplifies tensile loads due to overturning moments. Therefore, conservative anchor design considering maximum concentrated loads is imperative, moving away from conventional arithmetic average methods. The findings of this study provide practical guidelines for enhancing the reliability of high-performance protective structures.