Details:

Creators:
Wang, Yinhai ; Perrine, Kenneth A. ; Lao, Yunteng
Wang, Yinhai ; Perrine, Kenneth A. ; Lao, Yunteng Less -
Corporate Creators:
Transportation Northwest (Organization)
Corporate Contributors:
University of Washington ; United States. Dept. of Transportation
University of Washington ; United States. Dept. of Transportation Less -
Subject/TRT Terms:
[+]
Advanced Traffic Management Systems Freeway Management Systems Ramp Metering
Publication/ Report Number:
TNW2008-11
Resource Type:
Tech Report
Geographical Coverage:
United States
Edition:
Final report; Dec. 2008
Corporate Publisher:
Transportation Northwest (Organization)
NTL Classification:
NTL-INTELLIGENT TRANSPORTATION SYSTEMS-INTELLIGENT TRANSPORTATION SYSTEMS;NTL-INTELLIGENT TRANSPORTATION SYSTEMS-Freeway Management;NTL-HIGHWAY/ROAD TRANSPORTATION-HIGHWAY/ROAD TRANSPORTATION;NTL-OPERATIONS AND TRAFFIC CONTROLS-OPERATIONS AND TRAFFIC CONTROLS;
Abstract:
Ramp metering has been broadly accepted and deployed as an effective countermeasure

against both recurrent and non-recurrent congestion on freeways. However, many current ramp

metering algorithms tend to improve only freeway travels using local detectors’ inputs and

overlook the negative impacts on local streets. This may generate two problems: 1) the optimal

local settings may not result in a system-wide optimum in terms of traffic operations; and 2) the

increased congestion on local streets due to on-ramp overflow may counteract the gains in

freeway operations. To address these problems, we propose an area-wide ramp metering system

to improve the coordination of ramp meters for system-wide optimization and on-ramp overflow

minimization. Our experimental results show that our method can offer improved performance in

ramp metering operations under tested scenarios and also reduce the likelihood of on-ramp

overflow.

This novel strategy for active ramp metering is inspired by the principles of a computer

network congestion control strategy. In this strategy, certain types of congestion at a targeted

freeway location can be significantly reduced by limiting on-ramp vehicle flows to a fraction of

ramp demand and then additively increasing rates to avoid ramp queue spillover onto city streets.

This approach can be actively used to immediately curb the growth of traffic congestion and

therefore shorten travel delays. The effectiveness of this ramp metering approach has been

evaluated by microscopic simulation experiments. Our experimental results show that our

method can reduce system-wide travel delays in the tested scenarios by as much as 28.2% when

compared with the Fuzzy Logic ramp metering algorithm, and also reduce the frequency and

severity of on-ramp overflow. This indicates that this area-wide algorithm can provide benefit

when applied to urban freeway corridors for congestion mitigation.


Format:
PDF
Collection(s):
US Transportation Collection University Transportation Centers
Main Document Checksum:
[+]
urn:sha256:fed108a16e1a28a4a1b06c794d1e808027f59adb684171094a43aafcf04e9986
Download URL:
https://rosap.ntl.bts.gov/view/dot/17235/dot_17235_DS1.pdf
File Type:

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