As many bridges in the Netherlands are past their design-life and yet still have well-functioning steel superstructures, their bridge decks are often due to be replaced. FRP panels are promising alternatives to concrete decks for these renovation works due to their low density, f
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As many bridges in the Netherlands are past their design-life and yet still have well-functioning steel superstructures, their bridge decks are often due to be replaced. FRP panels are promising alternatives to concrete decks for these renovation works due to their low density, fast on-site construction time, and excellent acoustic and thermal properties. Many of these bridges are originally designed with hybrid interactions occurring at the connection level. Multiple connection types exist to ensure hybrid interaction with FRP decks. However, there is a gap in this field concerning a rapidly demountable connection able to transfer shear forces at girders with oversized holes. The injected reinforced resin connector is designed and aimed at achieving hybrid interaction through combined injection and preloading of the connector. The aim of this thesis is to find a viable design for this connection, and to test the connection under local compressive wheel loads. be able to design the connector and test it according to standards as expected to occur in real bridge applications, a FE-model of the bridge Nieuw-Vossemeer is made to assess expected loadlevels in the connection. The result is a combined list of loadlevels and geometrical tolerances that the connection will have to be able to sustain or perform under. Based on the resulting design requirements a main design is proposed. Here a steel bolt is embedded in the bridge deck and held in place by injection with reinforced resin. A steel plate separates the bridge deck from the girder flange, and creates a full steel clamping package. Multiple design alternatives are tested by the use of FE-models, where the variable is the type of steel plate used between the bridge
deck and the girder flange. The most viable design to continue experimental tests with is selected by its stiffness, ultimate resistance, and a qualitative assessment regarding expected cyclic endurance. The best performing concept is a steel plate with a spherical bottom, a diameter of 150mm and maximum thickness of 20mm. Extra FE-analyses are performed on a local scale, and take into account positional deviations from the most ideal situation. In addition a series of two static and two cyclic experiments has been performed. Apart from finding their respective resistances, the failure modes are assessed and compared together with the numerical analysis. The static tests show an ultimate resistance of 501kN, the numerical analysis shows a resistance of 498kN. Both the static tests and the numerical analysis failed ultimately due to delamination in the bottom facing of the FRP, the cyclic tests failed under a similar failure mode in the bottom FRP flange. On loading ranges with R = 0.1 it is found that the primary failure mode is a horizontal crack opening up in the bottom FRP flange, which propagates into the webs. The connection withstood 2 million cycles at 9kN - 90kN without damage. Subsequently, two different loadranges were applied to the two different tests, which failed after 394 thousand cycles at 13.5kN - 135kN and 34 thousand cycles at 18kN - 180kN. It is concluded that the spherical plate is able to function as a coverplate and withstands rotations, displacements and the required loadlevels as expected in bridge applications. The primary recommendation is to continue performing tests with a similar plate with a thickness of 15mm, as the current design overshoots the required resistance significantly.
The results show that the design is well able to sustain the required local compressive wheel loads, both in ultimate and cyclic resistance. With the ability to (de)mount these FRP panels quickly on-site, two main goals have been reached. Firstly, this brings the use of FRP panels in infrastructure closer, leading to reduced loads onto steel superstructures of existing bridges (and hence an extended lifetime). Secondly, a fundamental step has been set towards modular bridge design, where during failure only specific panels of the system have to be replaced. Together these developments can lead to a reduced impact of the construction industry on the environment.