STUDI PERENCANAAN ULANG STRUKTUR ATAS GEDUNG KULIAH BERSAMA 4 (GKB-4) UNIVERSITAS MUHAMMADIYAH MALANG DENGAN MENGGUNAKAN FLAT SLAB

The application of structures using flat slab method in Indonesia is quite rare. In the absence of beam structures, flat slab structures are vulnerable enough to withstand vertical and horizontal loads. Instead of beam elements, columns are used to distribute the working load from plates and portals to columns and foundations. In order to strengthen the structures facing shear forces caused by vertical and horizontal loads, the use of shear walls is strongly recommended to add retrofitting of building structures. Lecture Building 4 (GKB-4) constructed by using reinforced concrete portal structure feels very suitable to be modified by using flat slab method, considering the earthquake activity that happened in Malang is quite rare and Malang does not have history of earthquake which enough damage. The modifications made are to change the average size of the structural component dimensions, remove the blocks, reduce the shear number of walls, increase the shear wall thickness, and plan the drop panels in addition to strengthening the structure against the shear forces. After analyzing and calculating the data will be used for structural planning, such as thick plate 25 cm, thick drop panel 10 cm, 3 meter wide drop panel, etc. Through the application program STAAD.Pro V8i obtained drift ratio values in each direction of 0.0009, 0.0015, and 0.0014 which means the structure modeling in a stable state. Followed by plate reinforcement design using D16, D22 column reinforcement, and shear wall shear D16