Research on Static and Dynamic Tests of Steel Orthotropic Decks

Abstract

The static and crawl tests on the steel orthotropic deck of Xihoumen bridge were performed, which is to study the mechanical behavior and stress history curve of the construction details under traffic loading. The results of the tests reveal that, under the three-axle-weighted 30 t truck, the biggest value of longitudinal stress for the bottom of rib is 51.7MPa，the value of principal stress for the hole upper of diaphragm is 30.8MPa and transversal stress for the deck is 16.7MPa. the length of longitudinal influence line of transversal stress for the deck and vertical stress for the web of rib is about 7.2m. The influences of the principal stress for the opening upper of diaphragm and longitudinal stress for the bottom of rib are 5.4m and10.8m, respectively. Furthermore, the stress range and cycle times were analyzed by sluicing method. Under the condition of the craw tests, cycles of the key details that the stress range is larger than 5MPa for steel orthotropic deck are as follows: the longitudinal stress for the bottom of rib is three times and the biggest value of range is 60.1MPa: the transversal stress for the deck is three times and the biggest value of range is 26.8MPa: the vertical stress for the web of rib is four times and the biggest value of range is 16.1MPa: the principal stress for the hole upper of diaphragm is two times. Finally, Based on the results of dynamic test, and considering the specifications on impact coefficient by various countries, we suggest that impact coefficient shall be adopted in the calculation of fatigue of steel bridge deck; the joints on bridge deck 1+=1.75; for other parts, the calculation of each structure details of longitudinal ribs and deck, 1+=1.0; for calculating lateral girder (diaphragm) details, 1+=1.15.