1、 AN INFORMATIONAL GUIDE ON FENCING CONTROLLED ACCESS HIGHWAYS Prepared by the Task Force on Geometric Design of the Standing Committee on Highways Subcommittee on Design Published by the American Association of State Highway and Transportation Officials 444 North Capitol St., N.W., Suite 225 Washing
2、ton, D.C. 20001 November 1990 Copyright, 1990, by the American Association of State Highway and Transportation Officials. Printed in the United States of America. All rights reserved. This book, or part thereof, may not be reproduced without written permission of the publishers. EXECUTIVE COMMITTEE
3、1990 PRESIDENT: Kermit Justice, Delaware VICE PRESIDENT: Hal Rives, Georgia SECRETARY: Clyde E. Pyers, Maryland IMMEDIATE PAST PRESIDENT: James P. Pitz, Michigan ELECTED REGIONAL MEMBERS: Region I Dana Connors, Maine, 1990 Howard Yerusalim, Pennsylvania, 1991 Neil Wagoner, Louisiana, 1990 John R. Ta
4、bb, Mississippi, 1991 Bernard Hurst, Ohio, 1990 Darre1 Rensink, Iowa, 1991 Garth F. Dull, Nevada, 1990 Eugene Findlay, Utah, 1991 Region II Region III Region IV CHAIRPERSONS OF STANDING COMMITTEES: Duane Berentson, Washington, Administration Frederick P. Salvucci, Massachusetts, Planning James P. Pi
5、tz, Michigan, Highways Ronald Fiedler, Wisconsin, Highway Traffic Safety Franklin E. White, New York, Water Transportation Ben G. Watts, Florida, Aviation Ray D. Pethtel, Virginia, Public Transportation Horace B. Edwards, Kansas, Railway Conference Robert N. Bothman, Oregon, Research Arthur J. Rock,
6、 Jr., Vermont, Special Committee on Commissioner such as in areas of precipitous slopes or natural barriers. Wherever the safety of highway operation requires fencing, it should be considered as an essential part of the total highway facility, constructed as a highway item. Warrants The basic warran
7、t for fencing a highway is safety of traffic movement. To this end, fencing is warranted for one or more of the following purposes: 1. To keep animals off the highway. 2. To keep children, pedestrians, and bicyclists off the highway. 3. To prevent objects from being thrown onto a roadway from an ove
8、rcrossing structure. (For further information, refer to AASHTOs Guide for Protective Screening of Overpass Structures, November 1990.) - AASHTO TITLE FCAH-3 90 W Ob39804 O003624 TO2 Ownership of Fencing On facilities with full control of access, the access control fence should be State owned so that
9、 the State has complete control of the type of fence and is responsible for proper maintenance. On facilities with partial control of access, the fence may be owned and maintained by the State or the adjacent property owners, depending on the laws and policies of the particular state involved. Simil
10、arly, frontage road fences not needed for access control may be owned and maintained by the State or the adjacent property owners, depending on the States laws or policies. Time of Erection In many cases, the need for immediate fencing is obvious, and the proper type fence should be provided before
11、the highway is opened. A fence should be erected 2 as soon as the right-of-way is cleared. It may be necessary to install a temporary fence to deter encroachment into the construction zone and/or traveled way. In any event, a permanent fence should be erected as soon as the right-of-way is cleared a
12、nd it is practical. In cases where there is an existing adequate fence, the erection of a fence by the State may be deferred to such time as required, Types of Fence The lowest cost type of fence suited to the specific purpose should be provided. Consideration should be given to the likely extent an
13、d type of maintenance work as well as initial costs. Depending upon the specific purpose to be served, the following types of fence generally apply, either separately or in combination. Each highway agency should, however, develop its own guidelines for types of fence. 1. 2. 3. 4. Multistrand wire,
14、barbed or smooth: for controlling livestock. Woven wire: for controlling small livestock and in residential areas for controlling small children and pets. Chain link, usually 4 to 6 feet high: for controlling pedestrians in developed areas, particularly those containing multiple dwelling units, indu
15、strial establishments, business districts, parks, sports areas, schools, or other institutional buildings. Where bikepaths are being separated from the roadway, a minimum 4.5 foot high fence is recommended. Fences 7 to 10 feet high: for limited special areas where there are exceptional conditions. 3
16、 5. Miscellaneous types which serve as fence and sound barriers: fencesbarriers of this type can consist of stone, masonry block, precast concrete panels, wood rails, etc. Special fences other than above or in combination may be needed along highways where control of big game animals (elk, buffalo,
17、deer, big horn sheep, antelope, etc.) is necessary. Under most conditions, fences for controlling smaller game animals (cougar, bobcat, etc.) are not considered necessary. In some areas, mainly in the western States, there is a seasonal migration of deer and antelope between summer and winter feedin
18、g grounds. During these periods of migration, which are of short duration and which can be predicted within an accuracy of two or three weeks, these animals could create a serious problem for unwarned motorists. To deter these animals would require a fence 10 or more feet high. The cost of a continu
19、ous fence of this height would be excessive and the biologic effects on animal life would be undesirable. Intermittent sections of fence for the purpose of channeling these animals from habitual crossing sites to more suitable locations would be impractical since some of the animals would stray betw
20、een the fences along the sides of the highway and become trapped. The best solution to the condition created by these migrations crossing the highway appears to lie in the use of warning signs. The purpose of fencing may change within a relatively short length of highway and as a consequence, freque
21、nt changes in the type of fence may be suggested. Where the fence is continuous, changes in type of fence at short intervals are undesirable, and generally should be avoided. 4 Installation of higher type fences, such as chain link, should be made on the basis of existing and reasonable assured deve
22、lopment and land use. The type of fence and supporting posts should be considered separately in terms of the local area conditions of availability, cost, durability, safety, maintenance, etc. A statewide standard for a single type of wire or post may not be logical, and highway agencies should estab
23、lish standards accordingly. In deciding upon the type of material best suited to a particular purpose, consideration should be given to some of the characteristics of the fencing materials other than its deterrent qualities. Chain link fencing, for example, is available in various colors of vinyl co
24、atings. This may produce a more aesthetically pleasing appearance in environmentally sensitive areas. Chain link fencing, however, may restrict sight distance, particularly on curves and along lines approximately parallel to the direction of the fence and close to it. Woven-wire fence may also offer
25、 a restriction to view, but to a lesser degree than the chain link variety. A chain link fence is more of a trash and waste paper collector than other more open type fences and, in some areas, is apt to result in snow or soil drifting problems. Location of Fences Normally fences of the strand and wo
26、ven-wire type, as used in rural and some suburban areas, should be placed on or just inside the highway right-of-way line or access controlled line. For continuity, these fences may be erected substantially on a continuous line even though there may be some irregular right-of-way comers that are out
27、side the fence line. Under some suburban or urban conditions, and rural interchanges with considerable commercial development, a chain link fence would be similarly located. 5 Along urban highways with frontage roads within the right-of-way, fences for both animal, pedestrian, and bicycle control ma
28、y be located just inside the frontage road. The same condition for a limited length may occur in rural areas. In these cases the frontage road is a land service road and there may be no reason insofar as overall highway purposes are concerned to erect a duplicate fence of any type along the right-of
29、-way line. This may be done at the discretion of the property owner, but normally the necessary safeguards can be effected by a single fence. Where an otherwise continuous fence inside a frontage road (between the through-traffic lanes and the frontage road) is interrupted by ramps at an interchange
30、, it may be necessary to place sections of fence in the median to discourage pedestrians from crossing. Continuous fencing located inside the frontage road is not always warranted as a means of preventing indiscriminate vehicle crossing of the outer separation. Under some conditions, such controls a
31、re effected by cross-section design, planting, construction of guardrail, and policing, rather than by fencing. Gates Gates in fences along controlled access highways, through which access is provided to the right-of-way or through-traffic roadways, should be kept to a minimum number. Where provided
32、 they should be secured in a manner not detrimental to the highway operation. Each gate should be of the appropriate type and installation as fitting to the particular fence and condition. Gates may be needed in special cases as a means of outside access to utility facilities. 6 - AASHTO TITLE FCAH-
33、3 90 W Ob39804 0003629 594 W Where fencing is installed for range control, it may be necessary at interchanges and connecting roadways to use cattle guards instead of gates, Fences along the outside of frontage roads should have gates only to the minimum extent necessary to serve the abutting property. While there may be an advantage, such gates need not necessarily be under lock control where the control of access line lies inside the frontage road. 7
