Dinda Ainur Istiqomah, M. Mirza Abdillah Pratama, Cynthia Permata Dewi, Nindyawati, Karyadi, Poppy Puspitasari, Buntara Sthenly Gan
Maximum capacity and service limits are design requirements in structural elements such as reinforced concrete beams. Deflection is one of the parameters in evaluating service limits due to deflection determining the level of rigidity of the structure, load capacities, and serviceability of the structure. To achieve optimal deflection, the moment of inertia (I) and the modulus of elasticity (E) of the constituent material becomes the main parameters. Based on this, the purpose of this research was to design and evaluate the performance of graded concrete beams with different cross-sectional dimension ratios (b:h) and shear span ratios (a/d). In previous research, the graded concrete beam performs reasonably well in terms of reducing deflection, but its load capacity increases so it can be the one alternative solution for overcoming the service limits requirement of the beam. In this study, specimens of graded concrete beams were designed with concrete strength of 20 MPa in the first layer and 40 MPa in the second layer, with a height ratio of 1: 1. The test was carried out by placing reinforced concrete beams on two simple supports and applying load to two points. Finite element analysis was used to obtain deflection data and evaluated the performance of reinforced concrete beams. These research findings include: (1) The middle deflection of the span of the graded concrete beam at the time of the first crack is close to the deflection on the normal concrete beam of higher strength; (2) The deflection in graded concrete beams tends to be the same as that of normal low-strength concrete beams in yielding of reinforcement; (3) An increase in the cross-sectional dimension ratio (b:h) gives a downward trend in deflection data; (4) An increase in the shear span ratio (a/d) results in deflections that tend to get greater. © 2024 American Institute of Physics Inc.. All rights reserved.
Department of Civil Engineering, Faculty of Engineering, Universitas Negeri Malang, Jawa Timur, 65145, Indonesia; Department of Mechanical Engineering, Faculty of Engineering, Universitas Negeri Malang, Jawa Timur, 65145, Indonesia; Department of Architecture, College of Engineering, Nihon University, Fukushima, Koriyama, 963-8642, Japan
