In this study, a total of twelve beams continuous over two spans of 2,800 mm each were constructed and tested to failure. The beams were divided into two series. Series 1 included six T-beams under symmetrical loading, while Series 2 dealt with six rectangular beams under unsymmetrical loading conditions. In Series 1, the test variables included material type, assumed percentage of moment redistribution, spacing of lateral reinforcement in flange, arrangement of shear reinforcement, and serviceability requirements. In Series 2, three different loading cases were considered, I) loading both spans equally, II) loading both spans maintaining a load ratio of 1.5 and III) loading one span only. Under the loading case II, the parameters of reinforcing material type, assumed percentage of moment redistribution and serviceability requirements were investigated. The test results of both series showed that moment redistribution from the hogging to the sagging moment region took place in GFRP-RC beams which were designed for an assumed percentage of moment redistribution. In Series 1, the decrease of the stirrups spacing from 0.24d to 0.18d enhanced the moment redistribution percentage. Also, decreasing the spacing of lateral reinforcement in the flange from 450 to 150 mm improved the moment redistribution through enhancing the stiffness of the sagging moment region. In Series 2, the unsymmetrical loading conditions (loading case II and III) reduced the moment redistribution by reducing flexural stiffness in the heavily loaded span due to extensive cracking. Regarding serviceability in both series, the GFRP-RC beam designed for the same service moment calculated from the reference steel-RC beam, was able to meet the serviceability requirements for most types of the structural applications. / February 2017

Yes / The flexural performance of geopolymer concrete (GPC) T-beams reinforced longitudinally with GFRP bars under a four-point static bending test was investigated. Six full-scale simply supported T-beams were cast and tested; one control specimen was made with ordinary Portland cement concrete (OPCC), while the other five beams were made of geopolymer concrete. The G-GPC2 was designed to attain the same theoretical moment capacity as the G-OPCC6 control beam. The main parameters investigated were the reinforcement ratio of ρ_f/ρ_b= 0.75, 1.05, 1.12, 1.34 and 1.34 for G-GPC1, G-GPC2, G-GPC3, G-GPC4, and G-GPC5, respectively, and compressive strength of geopolymer concrete. Based on the results of the experiments, the ultimate strain of GPC did not show the same behaviour as that of OPCC, which affects the mode of failure. The beam capacity and deflection were, respectively, overestimated and underestimated using the ACI 440 2R-17 predictive equations.

Yes / This paper presents test results of six full scale reinforced concrete continuous T beams. One beam was reinforced with glass fibre reinforced polymer (GFRP) bars while the other five beams were reinforced with a different combination of GFRP and steel bars. The ratio of GFRP to steel reinforcement at both mid-span and middle-support sections was the main parameter investigated. The results showed that adding steel reinforcement to GFRP reinforced concrete T-beams improves the flexural stiffness, ductility and serviceability in terms of crack width and deflection control. However, the moment redistribution at failure was limited because of the early yielding of steel reinforcement at a beam section that does not reach its moment capacity and could still carry more loads due to the presence of FRP reinforcement. The experimental results were compared with the ultimate moment prediction of ACI 440.2R-17, and with the existing theoretical equations for deflection prediction. It was found that the ACI 440.2R-17 reasonably estimated the moment capacity of both mid-span and middle support sections. Conversely, the available theoretical deflection models underestimated the deflection of hybrid reinforced concrete T-beams at all load stages.

This work aims to investigate the flexural behaviour of continuous hybrid reinforced concrete T-beams (HRCT). The investigations consist of three parts; the computational part, the experimental part and the finite element analysis. The computational part included two parts, the first one is developing an analytical programme using MATLAB software to investigate the moment-curvature behaviour of HRCT-beams and to design the experimental specimens. This was followed by the experimental part, where six full-scale reinforced concrete continuous T beams were prepared and tested. One beam was reinforced with glass fibre reinforced polymer (GFRP) bars while the other five beams were reinforced with a different combination of GFRP and steel bars. The ratio of GFRP to steel reinforcement at both mid-span and middle-support sections was the main parameter investigated. The results showed that adding steel reinforcement to GFRP reinforced concrete T-beams improves the axial stiffness, ductility and serviceability in terms of crack width and deflection control. However, the moment redistribution at failure was limited because of the early yielding of steel reinforcement at the beam section that did not reach its moment capacity and could still carry more loads due to the presence of FRP reinforcement. The second part of the computational part included the comparison between the experimental results with the ultimate moment prediction of ACI 440.2R-17, and with the existing theoretical equations for moment capacity, load capacity, and deflection prediction. It was found that the ACI 440.2R-17 design code equations reasonably estimated the moment capacity of both mid-span and middle-support sections and consequently predicted the load capacity of the HRCT-beams based on fully ductile behaviour. However, Qu's and Safan's equations underestimated the predicted moment and load-capacity of HRCT-beams. Also, Bischoff's and Yoon's models underestimated the deflection at all stages of the load for both GFRP and HRCT- beams. For the numerical part, a three-dimensional finite element model has been developed using ABAQUS software to examine the behaviour of HRCT-beams. The experimental results were used to validate the accuracy of the FEM, where an acceptable agreement between the simulated and experimental results was observed. Accordingly, the model was used to predict the structural behaviour of continuous HRCT-beams by testing different parameters.

The subject of my diploma thesis is a detailed static calculation of the post-tensioned concrete road bridge across Bystrica creek near Banska Bystrica in Slovakia. The bridge is element of turning ramp a motorway R1. The spatial curvature continuous bridge has 9 fields. It was made a spatial curvature computational model of the bridge for a structural analysis. The model was comparison with a straight computational model of the bridge. It is made comparison effect of the construction bridge in stages on the size of the internal forces too. The load-bearing structure was checked according to CSN EN 1992-1-1, CSN EN 1992-2 and CSN 73 6214.