HYBRID COMPOSITE STRUCTURAL FRAMES FOR MULTI-HAZARD RESILIENCE IN URBAN INFRASTRUCTURE

Abstract

Urban environments face increasing exposure to multi-hazard events, including earthquakes, high winds, blasts, fire, and progressive collapse. Conventional reinforced concrete and steel structural systems often struggle to deliver the required levels of resilience, ductility, and rapid recovery. This study proposes an innovative hybrid composite structural frame that integrates Fiber-Reinforced Polymer (FRP) composites with high-performance concrete and steel to enhance strength, ductility, deformation capacity, and multi-hazard resistance. FRP is incorporated in strategic zones—such as beam–column joints, exterior frames, and weak-axis bending regions—to control cracking and delay structural degradation. High-performance concrete provides compressive strength, while steel ensures robust load redistribution under extreme demands. The hybrid system leverages the complementary mechanical behavior of all three materials, leading to superior energy dissipation and controlled failure modes. Experimental evaluation included lateral cyclic loading, axial compression, fire exposure, and impact resistance. Results show significant improvement in drift capacity, reduced residual deformation, enhanced post-event recoverability, and improved resistance to brittle failures. Multi-hazard simulation using finite element analysis validated the efficiency of the hybrid composite frame in redistributing stresses and preventing collapse under compound hazards. The proposed system offers a promising direction for resilient urban structural design, supporting sustainability goals and future-proof infrastructure development.