95678 - TECNICA DEL TRAFFICO E DELLA CIRCOLAZIONE M

Learning outcomes

With the acquisition of the credits the student is provided with principles, methodologies and operational tools for the analysis, simulation, control and monitoring of traffic flows in transport systems. He also acquires the necessary knowledge for the analysis and optimization of the performance of the elements of a transport network, with special regard to the organization and management of traffic in road and rail transport systems.

Course contents

General concepts and definitions:
- Course outline
- The transport supply sub-system in the general framework of transport system engineering
- Traffic flow theory: general principles
- Concept and evaluation of Level Of Service (LOS)
Uninterrupted flow infrastructures:
- Fundamental variables and macroscopic, steady-state flow models (Greenhields, Greenberg, Northwestern Underwood, Newell)
- Measurement of flow variables, methods and technologies
- Capacity in ideal conditions
- LOS of a freeway section
- LOS of two-lane highways
- Continuous flow models and shock waves, LWR model, higher-order models.
- Microscopic flow models (car-following models, GM model, IDM, Gipp's model)
Basic principles of queuing theory:
- Basic elements of a queue system, theoretical fundamentals
- Poisson single or multiple servant queues: MM1 and MMn
- Non-Poisson queues: MG1, MD1. Herlangian queues
- Examples
Signalized intersections
- Basic definitions: Traffic light cycle and phases, Lane Groups; Saturation Flow
- Real Saturation Flow estimation
- Capacity, Saturation degree and flow ratio of a lane group
- Delay and LOS of a traffic light intersection: Webster, Doherty, Robertson-Whiting, HCM methods.
- Webster and HCM methods for cycle and phase definition
- Yellow plus all-red time estimation
- Traffic light coordination
Unsignalized Intersections
- Type of intersection; allowed manoeuvres and priority rules, rank of a manoeuvre.
- Definition and estimation of critical-gap and follow-up-time
- Critical volume, potential and actual capacity of each manoeuvre
- LOS delay and queue length estimation

- Direct estimation of critical gap: Raff's and Troutbeck methods
Roundabouts
- Right of way, design characteristics
- Review of regulatory framework of roundabouts - European classification and FHWH classification
- Italian classification: DM 19/04/2006
- Methods of capacity and LOS estimation: experimental/empirical (Kimber), analytical (HCM, FHWA, ARRB-SIDRA)
Railway circulation and capacity
- Structural and functional characteristics of the railway system
- Speed and braking characteristics of trains
- Rail networks: lines and nodes (stations)
- Traffic safety: detection and control equipment
- On-line and station circulation regimes
- Estimation of line capacity: Lehner curves; UIC and RFI methods for line capacity calculation
- Capacity of a railway node: Potthoff method
- The SCMT system
- High Speed Rail: General features; ERTMS - ETCS operating levels; AV/AC management

Readings/Bibliography

Slides and lecture notes

Teaching methods

Frontal lectures, exercises, in-depth seminars.

Assessment methods

Written exams: numerical exercises, open questions, multiple choice questions.

Office hours

See the website of Luca Mantecchini