Pengaruh Penambahan Tulangan Tekan Eksternal terhadap Perilaku Struktur Beton Bertulang
DOI:
https://doi.org/10.5614/jts.2021.28.1.4Keywords:
Pelat baja, Tulangan eksternal, Kapasitas, Kekakuan, dan DaktilitasAbstract
Abstrak
Daktilitas struktur merupakan syarat yang harus dipenuhi pada struktur tahan gempa dimana struktur mampu berdeformasi besar pasca leleh tanpa runtuh. Kondisi demikian hanya dapat terjadi jika struktur direncanakan berdasarkan kaidah strong column weak beam dimana ketika terjadi gempa kuat sendi plastis hanya boleh terjadi pada balok di muka kolom kecuali pada kolom lantai dasar. Empat benda uji balok 180 mm50 mm400 mm ditumpu sendi rol dengan jarak antar tumpuan 2250 mm dikenakan pembebanan four point bending dengan dimana jarak beban ke beban 630 mm. Tipe I terdiri dari dua benda uji dengan kuat tekan fc=47,280 MPa dan rasio tulangan dan r=26,00 % rb dan dua lainnya adalah tipe II dengan fc=38,168 MPa dan r = 59,02 % rb. Masing- masing tipe satu balok untuk benda uji kontrol dan satu lainnya untuk benda uji dengan penambahan pelat baja dengan lebar 50 mm dan tebal 5 mm di permukaan beton tekan. Peningkatan kapasitas, kekakuan dan daktilitas untuk tipe I masing-masing sebesar 27,50 %; 32,02 % dan 103,67 %, sedangkan untuk tipe II peningkatannya masing-masing sebesar 16,30 %; 0,77 % dan 21,24 %. Semakin tinggi rasio luas pelat dan luas tulangan tarik Ap/ As semakin besar pengaruhnya dalam peningkatan kapasitas, kekakuan dan daktilitas penampang beton.
Kata-kata Kunci: Pelat baja, Tulangan eksternal, Kapasitas, Kekakuan, dan Daktilitas.
Abstract
The ductility requirements of a structure are defined by the degree of deformation after steel yielding induced by the earthquake responses. Such a condition can only be achieved when the structure is designed based on the strong column weak beam philosophy, where the plastic hinges only form in the beam at the column face due to seismic force, except the first floor. Four 180 mm50 mm400 mm beams supported by hinge and roll with 2250 mm span subjected to four-point bending, where load to load span is 630 mm. Type I consists of two specimens with concrete compressive strength fc=47.280 MPa and reinforcing steel ratio r=26,00 % rb, and two others are type II with concrete compressive strength fc=38.168 MPa, and reinforcing steel ratio r=59,02 % rb. Each types one beam is the controlling specimen, and the other one is the specimen that has to be attached steel plate with 50 mm width and 5 mm thickness on compression concrete fiber. Increased capacity, stiffness, and ductility of type I are 27.50 %, 32.02 %, and 103.67 % respectively, while the increase of type II is 16.30 %, 0.77 %, and 21.24 % respectively. The higher the ratio of the steel plate area and the tensile reinforcement area Ap/As, the greater the effect on the increasing capacity, stiffness, and ductility to the concrete section.
Keywords: Steel plate, External bar, Capacity, Stiffness, and Ductility.
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