Comparative Seismic Performance and Cost Analysis of G+12 Reinforced Concrete, Steel, and Steel–Concrete Composite Buildings

Abstract

Steel, concrete and composite members each have distinct mechanical behaviors that create challenges in building design. Steel elements, often formed from thin plates, are susceptible to local and lateral buckling, making uniform-thickness fabrication and stability checks critical. Concrete members, though generally thick and less prone to buckling, are vulnerable to long-term creep and shrinkage, which can affect stiffness and induce additional stresses. To capitalize on the advantages of both materials while mitigating their drawbacks, steel–concrete composite systems have been developed. These systems provide high stiffness, improved fire resistance, rapid construction, and economic efficiency, and are widely adopted in multi‑storey framed buildings. In typical composite construction, I‑section steel beams and H‑section steel columns support a composite floor slab formed by profiled steel decking acting as permanent formwork and tensile reinforcement for cast-in-situ concrete. In this study, multi‑storey RCC, steel, and composite buildings are modeled in ETABS 2015 (v15.2.2). All three structural systems are analyzed using both the static seismic coefficient method and the dynamic response spectrum method. Key seismic performance parameters—natural period, frequency, storey displacement, storey drift, storey shear, storey moment, and storey stiffness—are evaluated and compared to investigate and quantify the seismic behavior of RCC, steel, and composite multi‑storey buildings.