REDUCTION OF TOTAL TIME SPENT IN A FREEWAY SYSTEM BY ON-RAMP METERING

TABLE OF CONTENTS

ABSTRACT 1

1. INTRODUCTION

2. TOTAL TIME SPENT (TTS) ON THE FREEWAY SYSTEM

2.1 Definitions and Assumptions
2.2 Calculation of TTS
2.3 Some Results on TTS Minimisation

3. MODELING ASSUMPTIONS

4. A COUNTEREXAMPLE ON TTS-REDUCTION

4.1 A Freeway Without Off-Ramps
4.2 A Freeway With Off-Ramps
4.3 Interpretations

5. AN ILLUSTRATIVE EXAMPLE

6. CONCLUSIONS

REFERENCES 17

ABSTRACT

The report shows in a straightforward way that reduction of the total time spent by all drivers in an isolated freeway system is linearly related to a weighted sum of exit volumes. Using this result and fairly general modeling assumptions, a counterexample is presented providing evidence for the fact that on-ramp control may lead to reduction of total time spent in the freeway system. A final simple example illustrates the main statements. This report reproduces an unpublished manuscript, written in 1987, that was never submitted for publication.