WEIGHT ESTIMATION OF MOVING TRUCK FROM BRIDGE ACCELERATIONS

Vehicular weight in road network is crucial information for road and bridge design and maintenance. Many methods of weight identification have been proposed. The bridge weigh-in-motion (B-WIM) method is an alternative that becomes more popular due to its difficult visibility by the truck drivers and portability. Existing bridge weigh-in-motion (B-WIM) system utilizes the signals from strain gauges installed beneath the bridges to estimate the weight of the moving vehicles. Therefore, this research studies the feasibility and effectiveness of weight determination of moving vehicles from bridge accelerations since the installation of accelerometers is more convenient and much cheaper. The average acceleration discrete algorithm which was found to be effective to identify the non-moving dynamic loads acting on buildings is selected and extended to the case of moving load identification of truck passing over the bridge. To study the effectiveness of the proposed weight estimation method, the vehicle-bridge interaction is simulated. The obtained bridge acceleration is employed as the input for weight estimation of passing truck. This load estimation is an inverse identification problem. Numerical examples of a simply-supported bridge under passing truck are conducted to investigate the accuracy and efficiency of the proposed method. Effects of the axle spacing, mass and speed of vehicle on the accuracy of the identification results are reported.