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This paper presents a comparison designed to manipulate performance characteristics of ten reinforced concrete beams with and without openings under a single monotonic maximum stress at mid-span, depending on the configuration and size of the openings, using the ABAQUS/CAE finite element approach package. The cross-section, arrangement, and opening sizes of all the beams were identical to those of the test beams. The goal of the experimental comparison was to check that all simulation processes were proper and adequate. The numerical analysis results showed that in terms of the failure load, there was a 94 percent agreement between experimentally tested and numerical analysis results. In addition, it was shown that concentrated shear stresses at the corners of the openings causing the failure of the posts between the openings. The numerical study revealed that the influence of increasing main longitudinal steel reinforcement by 28% and 44% more efficient to enhance the ultimate load capacity by rates of 7.61% and 9.61%, respectively, compared to increasing the compressive strength of the beams by 24 %, which led to increasing the ultimate load capacity by 3.72%. Therefore, From the standpoint of difficulty and timesaving, the finite element approach is a very dependable technique for investigating the nonlinear behavior of beams with many apertures.

This paper reports on a study to determine the effectiveness of using externally bonded carbon-fibre-reinforced polymer composite sheets as a method of increasing the shear strength of reinforced concrete beams. The investigated parameters were the amount and distribution of the composite, the bonded surface and fibre orientation. The overall behaviour of the test beams up to failure, the onset of cracking and crack development with increased load and ductility were recorded. Beams strengthened with 90° U-wrap composite sheet showed a large increase in ultimate-load-carrying capacity compared with beams strengthened with 90° composite web strips of 50 mm width. Decreasing the spacing between the strips was also found to be efficient, while using 45° strips rather than 90° strips did not produce a remarkable increase in shear capacity. Depending on the variables investigated, the externally bonded composite increased the shear capacity by 34–75% compared with the control beams. Some previously published models were found to give consistently good correlations with the test data, with acceptable coefficients of variation. However, the model proposed by the American Concrete Institute showed unsatisfactory performance because of its empirical nature and use of an inappropriate model for bond length.

Spaceframe is a structural roofing system that generally made of steel tubes connected by ball joints which is called MERO jointed space frame structures and mostly used for covering large space area. In addition, some advantages could be obtained with such a system, for example lower weight, high strength-to-weight ratio and low cost. This study aims to use such a known roof structure for a composite structure in which Ultra-High-Performance Concrete slabs are used to withstand various loads as a structural floor system. Various inclinations of the main elements for space frames were tested, namely 30 °, 45 ° and 60 °. The composite effect is accounted for by testing composite and non-composite samples. The test results were evaluated and compared against several performance indices, such as: Ultimate load, stiffness, hardness, ductility, ductility index and absorbed energy. Test results have shown that spaceframe models with an angle of 60 ° have the highest load-carrying capacity compared to other angles and the highest toughness compared to various techniques. Putting together 40mm UHPC slab panels reflected a slight increase in the models used in this study than traditional spaceframe samples.