Abstract
This study develops a calculation method of axle weights in orthotropic steel deck bridges. Curve fitting to strain due to live loads from influence lines calculates vehicle axle weights with the least square method. The curve fitting is done in a longitudinal rib and a transverse rib. The accuracy is high in the weight ratio among the axles in the vehicle in the results from the longitudinal rib and in the gross weights from the transverse rib. Hence, the results from the longitudinal rib are regarded as temporary axle weights; then, the temporary gross weight is calculated from the summation of the temporary axle weights. A correction coefficient is obtained by taking a ratio of the temporary gross weight and the gross weight calculated from the strain responses of transverse rib. The temporary axle weight is corrected to the axle weight by multiplying the correct coefficient. The standard division of the error is from 5.87% to 7.87% in the 95% confidence interval. When applied for one week dynamic strain data, axle weight over 100kN passes 1,783 times and that over 200kN does 31 times.
