Experimental testing of fatigue life and improvement of trapezoidal longitudinal ribbed on bridge decks

All over the world, many long-span steel bridge structures used the orthotropic trapezoidal longitudinal ribbed steel bridge deck as one of the basic building blocks in the structural system, for distribution of traffic loads in decks and for the stiffening of slender girder plate elements in compression[1]. This thesis involves a laboratory test of two specimens, as well as a simulation of the model by the finite element method simulation (Abaqus program). The specimens is a trapezoidal longitudinal ribbed. Through laboratory testing, the two specimens will be loaded to demonstrate its impact on fatigue cracks. One of the two specimens will be testing by strain gauge test to find the strain of the specimens and comparing with the strain that will be obtained from simulation by Abaqus program and hand calculation. The number of cycles that cause fatigue cracks will be taken into consideration to measure the size of fatigue cracks. When the fatigue failure was found before many years and made problems for orthotropic decks, it is necessary to identify the areas where fatigue cracking occurs; and therefore to study the case and find solutions to treat it. By hand calculation, depending on the output results from laboratory test, the values of strain for the specimens can be calculated. A parametric study was performed using 3D finite element analysis simulation to investigate the effects of welding and the thickness of the plate on the value of stress and displacement for the specimens.