M42 Active Traffic Management
SIAS developed an S-Paramics model of the M42 between Junctions 3A and 7. The model included ITS capability in order to demonstrate key operational regimes being proposed for this section of motorway.
The S-Paramics model included the dynamic interaction between traffic (detected by simulated MIDAS loops) and variable speed limits and lane indicators, in order to allow hard shoulder running on the motorway during times of peak demand. The proposals are part of an overall Demand Management Strategy, which has since been implemented on the M42, and which is likely to be extended to other sections of the UK motorway network. The S-Paramics ATM controller was used to manage the hard shoulder running and lane closures, in addition to regulating slip road flows.
The objectives of the S-Paramics modelling were to demonstrate the integrity of the approach to key stakeholders, and to explore any operational issues arising. Tests were required for a range of situations, including lane closures on the unaffected carriageway and the closure of slip roads because of queue build up.
The model was used to test different scenarios for driver utilisation of the actively managed hard shoulder. The simulation allowed the user to assess how access management (slip road flow regulation) influenced the varying uptakes of usage of the hard shoulder services. This important dynamic interaction needed to be understood before access management of any form could be implemented. The model also simulated the signal controlled roundabout at Junction 6 as well as representing the interaction of variable demand with the complex lane changing associated with the hard shoulder running.
The hard shoulder and lane restrictions can be manually activated through the S-Paramics ATM controller interface. The ATM controller can also automatically manage the hard shoulder running, lane closures, slip road flow regulation and emergency vehicle access when an incident occurs.