ABSTRACT

Vehicular loads on bridges have large variations. Toward rational maintenance of bridges, vehicular loads for each bridge need to be evaluated. While Bridge Weigh-In-Motion (BWIM) has long been studied, the need for strain gauge installation and the calibration with heavy vehicles was a factor against wide-spread use of BWIM. Authors propose BWIM based on wireless accelerometer without strain gauge installation. Wireless accelerometers measure acceleration responses of a steel box girder bridge for more than a week continuously. Deflection is estimated by combining the vertical and longitudinal acceleration measurement. Vehicular weight is evaluated using a genetic algorithm based on the estimated deflection. Vehicle load distribution is estimated.