ABSTRACT
A great need for bridge maintenance is the development of economical WIM technique. Although relatively inexpensive, the conventional BWIM requires the strains of transverse stiffeners for supplemental information in addition to the strains of main girders. Effort has been made to conduct BWIM only by the strains of transverse stiffeners. It was successful for truck-load estimation and then extended to estimate axle loads. The extension encountered difficulty: when two trucks run side by side, axle loads interact in some bridges. In the present study, the problem is solved by considering the interaction in a consistent way. The legal limit of the truck load is 245 kN in Japan. Overloaded trucks can run only by permission from the authority. Still quite a few trucks exceeding 245 kN run on highways. The traffic loads due to those heavy trucks are investigated by the proposed method.
