1. Trucks on Motorways in the Netherlands A survey of the role of trucks in traffic flow AVV Transport Research Centre Ministry of Transport Onno Tool 14-06-2006

2. 2 Content Introduction The prohibition to overtake by trucks Future scenario’s and the expected growth of freight traffic Further investigations on the impact of trucks on the traffic flow Discussion

3. 3 Introduction No distinction between passenger cars and trucks –Of course In motorway design (width of lanes) –In the models a truck is 1.9 passenger car No specific separate infrastructure – On two motorways a specific truck lane (but only a few kilometers, in total < 15 km) Important rule on the NL motorways: Keep right Only a few measures specific for trucks – Restrictions on axle loads (a few spots with weigh in motion) – Prohibition to overtake Notice: different maximum speed limits 80km/h vs. 120 km/h

4. 4 Why a prohibtion to overtake? Better use of the lanes, a little higher capacity (max 3%) Higher speed at the left lane Increase of the traffic safety –No changing lanes by heavy vehicles –More stable/homogeneous traffic flow 80-90% support among passenger car drivers Of course less support among truck drivers

5. 5 History Start in June 1997 –185 km 2-lane motorway –fixed time periods of 07:00-09:00 and 16:00-18:00 Extension in October 1999 –750 km 2-lane motorway –Fixed time periods of 06:00-10:00 and 15:00-19:00 Extension in February 2002 –Introduction of the daytime period 06:00-19:00 Last extension in June 2003

6. 6 Survey current situation Only on 2-lane motorways In total 1100 km –06:00-10:00 and 15:00-19:00 (700 km) –06:00-19:00 (400 km) 50% of all motorways in NL 60% of all the 2-lane motorways in NL The measure also obligatory when using the shoulder lane (peak lanes)

7. 7, per 1 juni 2003 Current situation

8. 8 How? Signs beside the road F03F04 Extra sign with the specific time period Every 2 km and always after every acceleration lane (on-ramp)

9. 9 A B C

10. 10 Dynamic wish June 2003: no more static extensions, the current situation is the maximum Transport organisations: wish dynamic system Why: measure is only operative when necessary Higher acceptance among truck drivers, less offences of the measure Ministry of Transport: Effects on 3-lane motorways? Resulting in two test sides

11. 11, per 1 juni 2003 Situatie 1 juni 2003 inclusief uitbreidingen in spits- en dagvensters Test roads with a dynamic prohibition A2, 3-lane motorway Abcoude-Maarssen A2, A76 2-lane motorways Grathem- Kerensheide- Ten Esschen Utrecht Geldrop

12. 12 How? Extra Variable Message Sign –2-lanes: on gantry in the middle between the standard VMS –3-lanes: on gantry between the standard middle and right lane VMS

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14. 14 Not on every gantry Same restrictions as ‘static’ > 2 km

15. 15 Algorithm All extra VMS controlled by server with algorithm Uses status of the MTM system Uses total intensity, truck intensity and speed On line data Moving averages Clock Manpower

16. 16 Evaluation Operation time I.r.t. the fixed time periods Driver experiences / interviews (both passenger car drivers as truck drivers Traffic Flow (esp. 3-lane prohibition) Platoon forming of trucks Following distances/times Number of offences

17. 17 Some preliminary results System switches on/off 3-4 times a day Different patterns in operation per day of the week System works less hours than static design fixed time periods 80%- 90% of the drivers: dynamic is better than static 2-lane: offence rate doesn’t change significantly (1,5%) 3-lane: offence rate is 2% (was 9%) 3-lane: No significant effect on the capacity and travel times 3-lane: Obviously less lane changes by trucks High acceptance among drivers –80% among passenger car drivers –70% among truck drivers –Permanent Dynamic: 90% of all drivers

18. 18 Future Freight traffic grows faster (40%-80% towards 2020) Increasing interaction between these two users of our motorways Differences between passenger cars en trucks – Length: 5 vs 18 meters (notice study LZV length < 25 meters) – Weight – Height – Maximum speed limit: 80 km/h versus 120 km/h Prohibition to overtake by trucks? The main rule: Keep right Most of the on/off ramps are on the right side No separate infrastructure at this moment

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20. 20 Trucks are the fastest growing group of users of our motorways Trucks may have a significant influence in traffic flow and maintenance of road surface and bridges/viaducts Within Rijkswaterstaat there is little attention for this specific user Need for more detailed information

21. 21 Two studies The impact of trucks in the present situation Study on the possible effects with the present behavior projected to the future

22. 22 The impact of trucks in the present Following distances, platoon forming Speed distributions Capacity of 1 lane full with trucks When do passenger car drivers avoid the right lane Trucks and incident management Larger study on the underlying causes of incidents with trucks (Pieter van Vliet) Peak lanes, smaller lanes Road maintenance, construction sides Traffic signs earlier? International scan Experiments in the driving simulator

23. 23 Future study What role do trucks have in the damage in road surface and bridges/viaducts Intensities of trucks in the future Possibilities to separate these two users and bring back the interaction to an acceptable level? Effects at the on and off ramps? One homogenous traffic flow or two separated flows or a dynamic mix of these two variants?

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25. 25 Questions / Discussion