Volume 18, No. 5, 2021
Innovative Composite Material Reinforcement in the Structural Behavior of Concrete Beams with Holes
Sanjeev Kumar , Nikhil Garg , Anoop Bahuguna
Abstract
The purpose of this study is to improve the structural behaviour of perforated Ferro-cement beams. The goal was reached by a rigorous programme of experimental work. Additionally, mathematical models from theory were explored. Casting and testing fourteen 200x100x2000mm beams of reinforced concrete was part of the experimental programme. Beam B1 in Group 1 is the control beam, and it was cast with typical reinforcement consisting of two steel bars, 12 mm in diameter at the bottom and 10 mm in diameter at the top. A total of 16 of the 8mm steel stirrups. Beam B2 is identical to beam B1, except that polypropylene fibres have been added to the concrete matrix. Beams B3, B4, and B5 are the ones that are cast in the second group. Beam B3 was similarly strengthened to B2, but it included two apertures measuring 10 by 20 centimetres and positioned at equal distances from the beam's terminus. Both B4 and B5's beams were strengthened with two steel bars of 12mm diameter at the bottom and two steel bars of 10mm diameter at the top, sandwiched between two and four layers of welded steel meshes. Beams B6 and B7 are strengthened with one and two layers of expanded steel meshes, respectively, and include two apertures measuring 10x20cm that are spaced equally from the beam's ends. Beams B8 and B9, reinforced with one and two layers of fibre glass mesh for durability reasons, respectively, make up Group 4. These beams were cast and tested. Beams B10 and B11 in group five each have three holes and are reinforced with either four layers of welded steel meshes or two layers of expanded steel meshes. Beams B12, B13, and B14 in group 6 each have three apertures and are reinforced with either four layers of welded steel meshes, two layers of expanded steel meshes, or three layers of welded steel meshes. Beams with a span of 180 millimetres were subjected to four line loads. Strength, stiffness, cracking behaviour, ductility, and energy absorption qualities of the test beams were studied. The produced beams' behaviour was evaluated in comparison to the control beams'. The produced composite beams required two different analytical models to be tailored to them: one to estimate the first crack load using conventional strength of materials principles, and another to establish the ultimate strength and failure mode using ultimate strength theory. The testing findings demonstrated that the suggested beams could achieve high ultimate and serviceability loads, excellent fracture resistance management, high ductility, and strong energy absorption qualities. There is a close agreement for all beams between the experimental data and the results derived from the theoretical model. Because of this consensus, we know this model is sound.
Pages: 3107-3116
Keywords: Ferro-cement; Beams with openings; Experimental program; Structural behavior; Analytical model.