Investigating Truck Acceleration Capability at Metered On-ramps

Truck acceleration capability is an important parameter to update acceleration lane length design for metered on-ramps. This paper investigated the actual acceleration capability of three truck types at two existing metered on-ramps through video-based data collection method. A piecewise constant acceleration model was employed to capture truck acceleration characteristics. It was found that existing acceleration length will affect truck drivers’ acceleration behavior. For the study auxiliary lane type ramp, a two stage acceleration behavior was observed: in the first stage, acceleration rate decrease with speed increasing; when vehicles are approaching the merging area, drivers are more likely to accelerate at higher acceleration rates to catch up with the freeway mainline. In comparison, acceleration profiles indicate an exponential decreasing trend at the study taper type ramp. Results show that the truck acceleration performance data documented in the ITE Traffic Engineering Handbook are out-of-date. This paper also pointed out that the Green Book acceleration length design guidance is insufficient for trucks at metered on-ramps. Statistical results show that the average acceleration rates of light, medium and heavy trucks are approximately 2.82 ft/s2, 2.46 ft/s2, and 1.96 ft/s2, respectively. To accommodate the majority of drivers' acceleration to the desired merge speed, it was recommended the acceleration lane length design should be based on the 15th percentile acceleration performance data, which is approximately 30 percent lower than the average acceleration capability.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AT060 Standing Committee on Trucking Industry Research.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Yang, Guangchuan
  • Xu, Hao
  • Wang, Zhongren
  • Zong, Tian
• Conference:
  • Transportation Research Board 95th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2016-1-10 to 2016-1-14
• Date: 2016

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 15p
• Monograph Title: TRB 95th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Acceleration (Mechanics); Length; On ramps; Ramp metering; Trucks
• Subject Areas: Freight Transportation; Operations and Traffic Management;

Filing Info

• Accession Number: 01592770
• Record Type: Publication
• Report/Paper Numbers: 16-3010
• Files: TRIS, TRB, ATRI
• Created Date: Mar 4 2016 5:05PM