Skip to main content
Fachgebiete
Automobil + Motoren Bauwesen + Immobilien Business IT + Informatik Elektrotechnik + Elektronik Energie + Nachhaltigkeit Finance + Banking Management + Führung Marketing + Vertrieb Maschinenbau + Werkstoffe Versicherung + Risiko
DE
EN
Bücher
Zeitschriften
Themenseiten
Organisationspsychologie Projektmanagement Marketing Smart Manufacturing
Weitere Formate
Podcasts Webinare Technik Webinare Wirtschaft Kongresse Veranstaltungskalender Awards
Jetzt Einzelzugang starten
Zugang für Unternehmen
Referenzkunden
SLX-Digitalkonferenz: Zukunftswerkstatt 2024

Mehr Umsatz mit Top-Kontakten

Am 7. Mai erfahren Sie, wie Vertriebsteams Leadgenerierung, Leadnurturing und Leadstrategien effizient steuern können.
Erweiterte Suche
Anmelden
nach oben

2014 | Buch

An Overview of the Highway Capacity Manual and Its History Kapitel lesen Erstes Kapitel lesen

The Highway Capacity Manual: A Conceptual and Research History

Volume 1: Uninterrupted Flow

verfasst von: Roger . P Roess, Elena . S Prassas

Verlag: Springer International Publishing

Buchreihe : Springer Tracts on Transportation and Traffic

Enthalten in: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik" , Springer Professional "Wirtschaft"

Einloggen, um Zugang zu erhalten
insite
SUCHEN

Über dieses Buch

Since 1950, the Highway Capacity Manual has been a standard used in the

planning, design, analysis, and operation of virtually any highway traffic facility

in the United States. It has also been widely used abroad, and has spurred the

development of similar manuals in other countries.

The twin concepts of capacity and level of service have been developed

in the manual, and methodologies have been presented that allow highway

traffic facilities to be designed on a common basis, and allow for the analysis of

operational quality under various traffic demand scenarios. The manual also

addresses related pedestrian, bicycle, and transit issues.

This book details the fundamental development of the concepts of

capacity and level of service, and of the specific methodologies developed to

describe them over a wide range of facility types. The book is comprised of two

volumes. Volume 1 (this book) focuses on the development of basic principles,

and their application to uninterrupted flow facilities: freeways, multilane

highways, and two-lane highways. Weaving, merging, and diverging segments

on freeways and multilane highways are also discussed in detail. Volume 2

focuses on interrupted flow facilities: signalized and unsignalized intersections, urban streets and arterials. It is intended to help users of the manual understand how concepts,

approaches, and specific methodologies were developed, and to understand the

underlying principles that each embodies. It is also intended to act as a basic

reference for current and future researchers who will continue to develop new

and improved capacity analysis methodologies for many years to come.

Inhaltsverzeichnis

Frontmatter
An Overview of the Highway Capacity Manual and Its History
Abstract
In the earliest days of our nation, waterways were the primary means of transportation between various communities. There was little in the way of roads beyond rugged trails literally hacked out of the wilderness for horse-travel and the occasional wagon.
Roger P. Roess, Elena S. Prassas
The Fundamental Concept of Capacity
Abstract
The initial question is so easy: How big is the bucket? It is, however, deceptive in its simplicity. If the bucket is made out of steel or some other metal, its size and capacity are going to be fixed. A 5-gallon bucket is a 5-gallon bucket all of the time, and will carry a maximum of 5 gallons of liquid. Depending upon its density, however, the weight of 5 gallons of liquid can vary. Now, the question becomes more subtle: How much fluid can be moved from A to B in a 5-gallon bucket?? Depending upon the weight of the liquid and the strength of the carrier, the answer may vary. Perhaps the carrier can only lift a maximum of 50 lbs. If 3 gallons of a particular fluid weighs 50 lbs, that may be the maximum amount that can be moved in the 5-gallon bucket. Is that now its capacity? Then, would a lighter liquid change the capacity of the bucket to higher number (up to 5 gallons)? Now, what if the vessel was not a bucket, but a membrane of some type that was capable of expanding? The capacity might once again be dependent upon the weight and other characteristics of the fluid. Further, when stretched to its limit, the membrane may only remain intact for a few seconds before rupturing. Is the capacity of the membrane that amount of fluid in it for a few seconds before it bursts? Perhaps the capacity of the membrane is the maximum amount of fluid that can be retained in the membrane for an extended period of time. But, then, how much time describes a stable situation? Perhaps the issue is not so simple after all.
Roger P. Roess, Elena S. Prassas
The Fundamental Concept of Level of Service
Abstract
“What’s traffic like today?” This is a question we have all asked on numerous occasions when we prepare to make a trip as a driver or passenger in a car. What do we really mean, however, when we ask it, and what do we really expect in response? Are we interested in how fast traffic is moving? Are we interested in how congested our intended route is? Are we interested in how long we will have to wait at critical locations, like signalized intersections? Are we interested in how safe our trip will be? Are we interested in how comfortable our trip will be? The answer is, of course, “yes” to all of these. However, in answering all of these questions (assuming we can for any given case), we are creating a multidimensional matrix of possible conditions.
Roger P. Roess, Elena S. Prassas
Passenger Car Equivalents and Other Adjustment Factors
Abstract
It has been said that most of the methodologies of the Highway Capacity Manual involve a series of adjustments to what are relatively simple basic numbers.
Roger P. Roess, Elena S. Prassas
Overview of Uninterrupted Flow Methodologies of the Highway Capacity Manual
Abstract
“Uninterrupted flow” describes a type of facility; it is not a description of the quality of flow on a given facility or segment. Specifically, uninterrupted flow exists on any facility where there are no causes of interruption external to the traffic stream. Thus, a freeway is an uninterrupted flow facility, even when it is operating under breakdown conditions: in such cases, the causes of the interruption(s) to flow are interactions among vehicles that are internal to the traffic stream.
Roger P. Roess, Elena S. Prassas
Speed-Flow-Density Relationships: The Fundamental Basis of Uninterrupted Flow Analysis
Abstract
Speed-flow-density relationships are commonly calibrated to what are referred to as “ideal” or “base” conditions. The latter term is most commonly used in recent years, as the word “ideal” carries a quality connotation that is not necessarily accurate.
It is, however, important to know what the base conditions are, as highway capacity analysis methodologies most often apply various adjustment factors (Chapter 4) to the characteristics depicted for the defined base conditions.
Roger P. Roess, Elena S. Prassas
Basic Freeway and Multilane Highway Segments
Roger P. Roess, Elena S. Prassas
Analysis of Weaving Segments
Abstract
Weaving segments are created when merge junctions are followed by diverge junctions on a roadway. When the length of the segment is sufficiently short such that weaving maneuvers induce lane-changing activity that is in excess of that occurring on a comparable basic roadway segment without weaving, a weaving segment exists.
Roger P. Roess, Elena S. Prassas
Analysis of Merge and Diverge Segments
Abstract
The essence of uninterrupted flow facilities is that vehicles can enter and leave the traffic stream without requiring mainline traffic to stop. On freeways and many multilane highways, this is accomplished through on-ramps and off-ramps. Typically, on- and off-ramps consist of one lane, generally located on the right side of the freeway or multilane highway.
Roger P. Roess, Elena S. Prassas
Analysis of Two-Lane, Two-Way Highways
Abstract
The 1950 HCM [1] recognized the critical interaction between directional flows on a two-lane, two-way rural highway. Because of this, in 1950 and 1965, the models for two-lane highways dealt with both directions simultaneously.
In 1950, it was argued that to keep a single lane in one direction fully utilized, that passing opportunities had to be unrestricted by alignment, sight distance, or the existence of flow in the opposite direction. Since the basic capacity of a lane on a multilane facility had been established as 2,000 pc/h/ln, it was argued that this could be achieved on a two-lane highway only when there was no opposing flow to inhibit passing.
Roger P. Roess, Elena S. Prassas
The Future of the Highway Capacity Manual
Abstract
The Highway Capacity and Quality of Service Committee (HCQSC) will be preparing a major update to the 2010 HCM targeted for 2015. The primary contractor for this update is Kittelson and Associates, led by John Zegeer, a former chair of the HCQSC. It does so even though the 2010 HCM (which was only distributed in early 2011) has not been subject to extensive use, and little user feedback on it has been received. In some parts of the nation, it has not been officially adopted yet.
Roger P. Roess, Elena S. Prassas
Backmatter
Metadaten
Titel
The Highway Capacity Manual: A Conceptual and Research History
verfasst von
Roger . P Roess
Elena . S Prassas
Copyright-Jahr
2014
Electronic ISBN
978-3-319-05786-6
Print ISBN
978-3-319-05785-9
DOI
https://doi.org/10.1007/978-3-319-05786-6

Premium Partner

    Bildnachweise