Roads/Highways

Spatio-temporal Road Charge: A Potential Remedy for Increasing Local Streets Congestion

Bayen, Alexandre
Forscher, Teddy
2017

US population. Additionally, the emergence of large ridesourcing or transportation network companies (TNCs) totaling up to tens of thousands of registered drivers in single cities (all using the same routing app), there is further consolidation. Across the US, this has led to new or increased congestion patterns that are progressively asphyxiating local streets due to so-called “cut-through traffic.” As neighborhoods have started to realize this, private citizens have begun to resist, by trying to sabotage or trick the apps, or shaming the through traffic through opinion articles, and news...

Theory of highway traffic flow: 1945 to 1965

Newell, Gordon F.
1995

Although we lack a complete theory of the motion of individual cars, there are many simple facts that even the most inexperienced driver knows and there are others which we could determine through experiment if we thought these facts were worth the effort required to find them. The lack of such a theory however, should not deter us from constructing a framework of possible theories consistent with what is known and seeing if such an incomplete theory can give any useful information about the gross aspects of traffic.

Effects of HOV Lanes on Freeway Bottlenecks

Menendez, Monica
Daganzo, Carlos F.
2006

In this paper, the authors report on research that shows that high occupancy vehicle (HOV) lanes do not reduce the capacity of general purpose (GP) lanes. Empirical evidence, complemented with simulations, enable the authors to describe how to estimate total bottneleck capacity and how deploy HOV lanes without hindering vehicle flow. The authors also offer a dynamic strategy that increases a bottleneck's total discharge rate.

From Elevated Freeway to Linear Park: Land Price Impacts of Seoul, Korea's CGC Project

Kang, Chang Deok
Cervero, Robert
2008

Freeways and other high-performance roadway investments have long been considered vital to the economic well-being of metropolitan areas. Empirical research shows that limited-access, grade-separated freeway systems increase a region’s economic productivity by lowering transportation costs, a factor input to economic production (Aschauer, 1990; Boarnet, 1997). Past studies also reveal that urban land markets capitalize the benefit of proximity to freeway interchanges, especially for non-residential uses and in areas experiencing worsening traffic conditions (Gillen, 1996; Boarnet, 1997;...

City-Scale Transport Modeling: An Approach for Nairobi, Kenya

Daganzo, C. F.
Li, Yuwei
Gonzales, Eric J.
Geroliminis, Nikolas
2007

Traffic congestion poses problems for cities around the world, especially in rapidly growing and motorizing cities like Nairobi, Kenya. We show here how we plan to use in the context of Nairobi a new theory that relates the mobility provided by a city’s street network to the number of vehicles on the network (including private cars and public transport) and to key aggregate descriptors of both the street infrastructure and the public transport services. Conventional micro-simulation models require vast quantities of data and produce unreliable detailed results. The new theory asserts that...

Bus Lanes with Intermittent Priority: Screening Formulae and an Evaluation

Eichler, Michael
Daganzo, Carlos F.
2005

This paper evaluates strategies for operating buses on signal-controlled arterials using special lanes that are made intermittently available to general traffic. The advantage of special bus lanes, intermittent or dedicated, is that they free buses from traffic interference; the disadvantage is that they disrupt traffic. We find that intermittent lanes, unlike dedicated ones, do not significantly reduce street capacity. Intermittence, however, increases the average traffic density at which the demand is served, and as a result increases traffic delay. These delays are more than offset by...

Managing Evacuation Routes

So, Stella K.
Daganzo, Carlos F.
2009

This paper shows that evacuation routes, such as a building’s stairwell or an urban freeway, may discharge inefficiently if left unmanaged, and that setting priority rules can speed up egress. Therefore, a simple control strategy is proposed. The strategy is decentralized and adaptive, based on readily available real-time data. The strategy is shown to be optimal in two senses: (i) it finishes the evacuation in the least possible time, and (ii) it evacuates the maximum number of people at all times. In both cases, it favors the people most at risk. The results shed light on other traffic...

Deploying Lanes for High Occupancy Vehicles in Urban Areas

Cassidy, Michael J.
Daganzo, Carlos F.
2007

Simulations and field experiments in previous works suggest that a freeway’s general purpose lanes (those not dedicated to high occupancy vehicles) discharge vehicles from bottlenecks at an equal or higher average rate when one of the lanes is devoted to high occupancy vehicles than when it is not. This result was used in these previous works to develop formulae for the total discharge rate of bottlenecks, with and without dedicated lanes, as a function of the percentage of high occupancy vehicles in the traffic stream.This present paper extends these ideas by examining the effect of...

The Smoothing Effect of Carpool Lanes on Freeway Bottlenecks

Cassidy, Michael J
Jang, Kitae
Daganzo, Carlos F
2008

Real data show that reserving a lane for carpools on congested freeways induces a smoothing effect that is characterized by significantly higher bottleneck discharge flows (capacities) in adjacent lanes. The effect arises because disruptive vehicle lane changing diminishes in the presence of a carpool lane. The effect is reproducible across days and freeway sites: it was observed, without exception, in all cases tested.Queueing analysis shows that the effect greatly reduces the times spent by people and vehicles in queues. By ignoring the smoothing effect at one of the sites we analyzed,...

Multimodal Transport Modeling for Nairobi, Kenya: Insights and Recommendations with an Evidence-Based Model

Gonzales, Eric J.
Chavis, Celeste
Li, Yuwei
Daganzo, Carlos F.
2009

Traffic congestion is a growing problem in Nairobi, Kenya, resulting from rapidly increasing population and the crowding of motorized traffic onto a limited street network. This report includes analysis of the traffic conditions in Nairobi, the expected effects of further growth in demand, and a set of recommendations for how to improve the performance of the street network. Data describing motorized vehicle traffic was used to build a simulation model of Nairobi’s street network considering cars and matatus. This model was used to analyze traffic conditions at the city-scale under...