FRP strengthening of web panels of steel plate girders against shear buckling. Part-II: Fatigue study and cyclic series of tests

Abstract

The result of an experimental programme investigating a novel technique to strengthen web plates of steel plate girders against breathing fatigue due to shear buckling deformations ispresented. An experimental test series is present in which six specimens were manufactured to simulate the end panel of a plate girder; these were strengthened with an optimized FRP retrofit panel that was developed in an earlier phase of the research project, and tested for plate girder web shear buckling deformation mitigation under repeated cyclic loading, as well as ultimate load capacity enhancement. Test results and non-linear finite element modelling demonstrated the efficiency of this technique for stiffening the web against these deformation and thus reducing the critical stresses, consequently increasing the fatigue life of the girders by a factor ranging between three and seven, depending on the applied stress range and the fatigue resistance assessment method. The research demonstrates the applicability of this novel FRP strengthening technique to prolong and extend the fatigue life of existing plate girder bridges.

Review of annual progress of bridge engineering in 2019

“…Yao et al (2019) studied the influence of stop-hole size and spatial position on the reinforcement effect of steel bridge fatigue cracking, and determined the stop-hole parameters with reinforcement effect based on the test and theoretical analysis. A cold maintenance method for microdamage or zero-damage of existing structures by means of assembly-type connections such as pasting, bolting or glue-bolting hybrid connection was proposed by Kinoshita et al (2019b), Wang et al (2019b) and Al-azzawi et al (2019). Izadi et al (2019) used a method for strengthening fatigue cracking of steel truss bridges with Fe-SMA, and verified its applicability and feasibility using fatigue test.…”

Shear Strengthening of Slender Steel Beams Using Cold‐formed Stiffeners and Adhesives

“…Potential benefits can be achieved when low-weight stiffeners and adhesives are applied compared to the traditional method (steel plated stiffeners and welding): no traffic disruption is needed (easily to be applied) and the introduction of additional residual stresses is avoided. Up to the present date, the alternative techniques for web beam strengthening were concerned to the use of fibre reinforced polymers (FRP), due to the low-weight reinforcements [3][4][5][6][7][8][9][10][11][12]. Despite FRP have becoming more affordable in civil engineering over the years, this material is still expensive.…”

“…This drawback can be overcome when the low-weight stiffeners are directly applied using adhesives [6,7].…”

Investigation of Flexural Fatigue Behavior of Concrete Beams Reinforced with Intelligent CFRP‐OFBG Plates

“…e methods currently used for predicting the fatigue life of in-service bridges are generally based on fracture mechanics, strain, stress, damage variables, and energy method. Many researchers have done some work in this area [5][6][7][8][9][10][11][12][13]. In these studies, some have proposed and continuously improved the application of crack propagation equations in fatigue life prediction based on fracture mechanics [5][6][7][8].…”