REDESIGN OF GUNAWANGSA GRESIK APARTMENT BUILDING STRUCTURES USING COMPOSITE STEEL – CONCRETE STRUCTURES

Abstract

Composite structures are frameworks composed of two or more different materials combined into a single unit. This system offers advantages such as a 20-30% reduction in cross-sectional weight, increased stiffness, and efficiency in both construction methods and costs. This study aims to plan, analyze, and display internal forces acting on composite structures, with data collected from Gunawangsa Gresik Apartment. The analysis results show that using composite components in beams, plates, and columns meets standards like SNI 1729-2020 and AISC360-16. The obtained ɸPn value is significantly higher than Pu in steel-core concrete-encased composite columns, with ɸPn = 8275.63 KN > Pu = 4118.08 KN, nearly twice as much. Main beams also show significant results with ɸMn = 573 KN-m > Mu = 152 KN-m, nearly three times the Mu. The analysis also identifies the use of tension and shear connections with 3 M22 A325 bolts, structural bracing with hollow cylindrical PSR profiles of 168.3 mm, piles with a diameter of 45 cm and a depth of 15 meters, and 4 piles per foundation group. The pile cap dimensions are 300x300x100 cm, with rebar configurations of 6D25-250 per meter on both the X and Y axes.