Analytical study of load carrying capacity and torsional behavior of horizontally curved reinforced concrete deep beam

Abstract

Currently complex construction industry is drastically growing in the world especially in urban areas. In this progress the demand of constructing different types of structures are increasing. Among those structures, reinforced concrete deep beam is one type of structure that can be constructed in different arrangement in order to increase the resistance to torsion, shear, bending, fire, and temperature. Additionally, it is used to increase the beauty by fitting the geometric limitation of the building. Deep beam can be conventionally straight, horizontally curved, which is mainly used to carry huge concentrated load that act transverse to its plane. Horizontally curved deep beams have large resistance. It is used at rounded corners of buildings, modern highway bridges, construction of stadium and others. Therefore, detail studying of load carrying capacity and torsional behavior of horizontally curved reinforced deep beam is crucial in order to provide safe and economic deep beam structure. The torsional behaviuor of horizontally curved reinforced concrete deep beam and its load carrying capacitys had been discussed in the lesson of the study. The research focused on the effect of span length to overall depth (L/D) and length to radius (L/R) ratio on the torsional behaviour of horizontally curved reinforced concrete deep beam and its load carrying capacity. 21 samples of reinforced deep beam studied to investigate the load carrying capacity and torsional behavior using non-linear finite element analysis with ABAQUS Software package under concentrated load at mid-span of the beam. From these samples, straight reinforced concrete deep beam are three as control group and others are horizontally curved reinforced concrete deep beam. Concrete damaged plasticity model has been used to model the beam with C-25 grade concrete and steel reinforcement of having diameter of 𝜙4mm, 𝜙10mm and 𝜙12mm with 568Mpa, 596Mpa, 643Mpa steel yield strength respectively. In addition, eight-noded brick element had been used during modeling. Finally, from finite element analysis the load carrying capacity, the load deflection and load twisting angle curve had been obtained with respect to different length to depth (L/D) and length to radius (L/R) ratio. In conclusion, the analysis result showed, significant increase of internal torsion and decrease of load carrying capacity as length to depth (L/D) and length to radius (L/R) ratio increase for horizontally curved deep beam when compared torespective straight deep beam. The study also revealed that, the length to depth (L/D) has more effect when compared to length to radius (L/R) ratio.