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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. Content. Introduction The prohibition to overtake by trucks Future scenario’s and the expected growth of freight traffic
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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
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
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
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
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
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)
, per 1 juni 2003 Current situation
How? • Signs beside the road F03 F04 • Extra sign with the specific time period • Every 2 km and always after every acceleration lane (on-ramp)
A • B • C
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
, 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 Geldrop Utrecht A2, A76 2-lane motorways Grathem-Kerensheide- Ten Esschen
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
> 2 km • Not on every gantry • Same restrictions as ‘static’
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
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
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
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
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
Two studies • The impact of trucks in the present situation • Study on the possible effects with the present behavior projected to the future
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
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?