The dynamic component of bridge traffic loading is commonly taken into account with a Dynamic Amplification Factor (DAF) % the ratio between the dynamic and static load effects on a bridge. In the design codes, this factor is generally higher (more conservative) than in reality. Bridge weigh-in-motion systems use an existing instrumented bridge or culvert to weigh all crossing vehicles at highway speeds. A new method of obtaining DAF experimentally, using bridge weigh-in-motion (B-WIM) measurements, will be presented in this paper. Data from several bridge sites has been used to evaluate DAF with the proposed method. The results agree with numerical simulations and experiments performed in the ARCHES project: dynamic amplification decreases as static loading increases. The reason is that the extreme loading events, which include several heavy trucks with many axles, induce far smaller dynamic amplification than the lighter individual vehicles. This point is extremely important for assessment of bridges.
COBISS.SI-ID: 2273383
WIM systems are typically divided into two families of technologies, the pavement and the bridge ones. They both provide equivalent information about heavy duty vehicles crossing the system: exact time stamp, gross weight, axle loads and spacings, vehicle velocity, its category etc. While the pavement syst ems use strip or plate sensors embedded into the pavement, the bridge weigh - in - motion (B - WIM) ones apply sensors attached to the superstructure of existing bridges or culverts. Th is paper describes advancements in accuracy and long - term stability of the B - WIM system that were achieved within a 2 - year research project financed by the European Commission. Features that resulted in two to four accuracy class improvements according to European WIM specifications are novel axle detection method, better calculati on of experimental influence lines, consideration of measurement errors as well as correction of temperature and velocity effects. A new data quality assurance procedure also added value to the results of B - WIM measurements.
COBISS.SI-ID: 2274151
The Conference of European Directors of Roads (CEDR) has in recent years drawn eight tenders for applied research and development (R&D) projects, whose main objectives were to bring together the best expertise from across Europe to develop useful method ologies and to prepare guidelines and recommendations in the various fields of administrations activities, and to avoid duplication of similar research wor k that has been in the past performed in the individual member countries. Unlike the more basic research, funded by the European Commission under the Framework Programmes, the CEDRʼs calls always focus on the areas of the road administrations that are important for their operation. Most often the trans-national R&D program mes have asked for results in the areas of asset manage ment, traffic safety and environment, particularly related to the impact of climate change on the development and maintenance of road assets. Among the approximately fifty projects funded so far there were only a few dedicated to bridges. Two on the topic of effective management of bridges, with considerable contribution of Slovenian partners, are presented in this paper.
COBISS.SI-ID: 2272615