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The activity involved the design and execution of one of the most extensive traffic flow survey campaigns ever carried out to support the update of the Friuli-Venezia Giulia regional mobility model. The scope of work went beyond simple data collection, featuring a complex system for acquiring, integrating, and validating the information required to reconstruct regional mobility demand and update the simulation model used for transport planning.
The knowledge base was built by integrating numerous information sources. In addition to the data already available at the Regional Administration—including the existing model, the road network graph, motorway data, information from other agencies, and cellular data used to reconstruct Origin-Destination matrices—specific survey campaigns were planned and executed to fill data gaps and calibrate the model against field-observed data.
The primary component of the work consisted of vehicle flow count campaigns, carried out across two distinct periods of the year (summer and autumn) to represent varying network operating conditions. A total of 116 road sections were monitored, each surveyed continuously for 48 hours, generating a highly robust dataset in terms of both temporal and spatial consistency. The surveys were performed using a combined deployment of different automated monitoring technologies, including Doppler radar for vehicle counting and classification, and video systems with automated image processing, ensuring high levels of accuracy without causing traffic disruptions.
These surveys were complemented by a targeted Origin-Destination survey campaign conducted across 18 control sections through roadside interviews, supported by local law enforcement. This activity enabled the collection of qualitative information regarding routes, trip purposes, and travel characteristics, with a specific focus on freight transport flows, providing a critical contribution to the reconstruction of the demand matrices.
The reconstruction of freight mobility was further enhanced through an extensive stakeholder engagement initiative targeting the regional production system. Tailored questionnaires were distributed to manufacturing companies and logistics operators to gather information on inbound and outbound flow management, utilized transport modes, connections with ports, inland ports, and logistics hubs, as well as infrastructural bottlenecks and development outlooks for the regional logistics system.
Although the number of responses received was not statistically representative, the collected information provided valuable qualitative support for understanding freight transport dynamics. The cornerstone of the entire process was the integration of the survey data with Origin-Destination matrices derived from mobile network Big Data, which served as the baseline for reconstructing regional mobility demand. The utilization of cellular data, properly verified and calibrated against field survey campaigns, made it possible to overcome the representativeness limitations of traditional surveys alone, delivering a far more robust and spatially comprehensive reconstruction of demand.
The entire dataset was subsequently utilized to update the regional simulation model developed within the PTV VISUM environment. This process encompassed the revision of the network graph, updating the zoning system, estimating demand matrices for both light and heavy traffic, calibrating the model against observed field data, and preparing the simulation scenarios required for regional planning activities.
The project demanded integrated expertise across transport planning, survey campaigns, Big Data processing, transport modeling, and the construction of forecasting models. This effort successfully provided the Regional Administration with an updated tool for evaluating infrastructure interventions, mobility policies, and future transport system development strategies.
