PSI - Issue 62

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Mariano Angelo Zanini et al. / Procedia Structural Integrity 62 (2024) 815–823 Zanini / Structural Integrity Procedia 00 (2019) 000 – 000

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• Free traffic and normal transit speed : in this case, the bridge is considered to be open to traffic, therefore the most severe condition is considered between the one or two exceptional vehicle transit, depending on the structure length and positioned in the first lane, completed by the loading value reported in Fig. 1 assumed with a partial safety factor associated to the frequent load value. As regards the remaining lanes, the loads reported in Fig. 1 will always be considered with frequent values. Two exceptional vehicles can be considered, in the absence of specific information, with a distance equal to 3 meters. • Free traffic and 30 km/h maximum transit speed : this case involves the load transit with low speed and bridge open to traffic. The transit of a single exceptional vehicle on the first lane is considered, to which the frequent load reported in Fig. 1 can be added, considering the application of the latter at a minimum distance of 25 m from the EV. The other loading lanes are loaded as in the free traffic whit normal speed case. • Traffic suspended, 30 km/h maximum transit speed and no prescription on the transversal transit zone : in this case, the traffic is expected to be suspended, and the presence of a single EV on the roadway must be considered. In particular, if no limitation has been prescribed on the vehicle transversal transit area, the most severe position (i.e. eccentric with respect to the transversal section of the girder) for the safety checks must be considered. • Traffic suspended, 30 km/h maximum transit speed and prescription on the transversal transit zone : in this case, the traffic is suspended, therefore the presence of a single EV on the roadway can be considered. Unlike the safety checks with no prescription on the transversal transit zone, in this case a limitation on the transversal transit area is prescribed. The load model must therefore represent such type of limitation.

Fig. 1. EV loading schemes provided by MIT (2022).