HIGHWAY LOCATIONS CE 317
AND SURVEYS E n g r. I P D Q u i n e s
HIGHWAY LOCATIONS AND SURVEYS
GEOLOGIC
LAND USE EARTHWORKS
CONDITIONS
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HIGHWAY LOCATIONS AND SURVEYS
Selecting the location of a proposed highway is an
important initial step in its design. The decision to select a
particular location is usually based on topography, soil
characteristics, environmental factors such as noise and air
pollution, and economic factors. The data required for the
decision process are usually obtained from different types of
surveys, depending on the factors being considered.
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PRINCIPLES
OF HIGHWAY
LOCATION
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PRINCIPLES OF HIGHWAY LOCATION
Highway location processes involves the following phases:
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
Phase 2. RECONNAISSANCE SURVEY
Phase 3. PRELIMINARY LOCATION SURVEY
Phase 4. FINAL LOCATION SURVEY
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PRINCIPLES OF HIGHWAY LOCATION
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
Phase 2. RECONNAISSANCE SURVEY
Phase 3. PRELIMINARY LOCATION SURVEY
Phase 4. FINAL LOCATION SURVEY
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PRINCIPLES OF HIGHWAY LOCATION
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
In this phase, all of the available data are collected, examined,
and are usually carried out in offices prior to any field and
photogrammetric investigation. These data can be obtained from
existing engineering reports, maps, aerial photographs, and charts,
which are usually available at one or more of the state’s
departments of transportation, agriculture, geology, hydrology, and
mining. The type and amount of data collected and examined
depend on the type of highway being considered.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
In general, most data are obtained on the following characteristics of the area:
Ø ENGINEERING, including topography, geology, climate, and traffic volumes
Ø SOCIAL & DEMOGRAPHIC, including land use and zoning patterns
Ø ENVIRONMENTAL, including types of wildlife; location of recreational,
historic, and archeological sites; and the possible effects of air, noise, and
water pollution
Ø ECONOMIC, including unit costs for construction and the trend of
agricultural, commercial, and industrial activities
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PRINCIPLES OF HIGHWAY LOCATION
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
Phase 2. RECONNAISSANCE SURVEY
Phase 3. PRELIMINARY LOCATION SURVEY
Phase 4. FINAL LOCATION SURVEY
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PRINCIPLES OF HIGHWAY LOCATION
Phase 2. RECONNAISSANCE SURVEY
The objective of this phase of the study is to identify several
feasible routes, each within a band of a limited width of a few
hundred feet.
This phase are mostly considered on the construction of rural
roads because there are often little information available on maps
or photographs that are taken, and therefore aerial photography is
widely used to obtain the required information.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 2. RECONNAISSANCE SURVEY
Feasible routes are identified by a stereoscopic examination of
the aerial photographs, taking into consideration factors such as:
Ø Terrain and soil conditions
Ø Serviceability of route to industrial and population areas
Ø Crossing of other transportation facilities, such as rivers,
railroads, and highways
Ø Directness of route
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PRINCIPLES OF HIGHWAY LOCATION
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
Phase 2. RECONNAISSANCE SURVEY
Phase 3. PRELIMINARY LOCATION SURVEY
Phase 4. FINAL LOCATION SURVEY
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PRINCIPLES OF HIGHWAY LOCATION
Phase 3. PRELIMINARY LOCATION SURVEY
During this phase of the study, the positions of the feasible
routes are set as closely as possible by establishing all the
control points and determining preliminary vertical and
horizontal alignments for each. Preliminary alignments are
used to evaluate the economic and environmental feasibility of
the alternative routes.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 3. PRELIMINARY LOCATION SURVEY
ECONOMIC EVALUATION
Economic evaluation of each alternative route is carried out to
determine the future effect of investing the resources necessary to
construct the highway. Factors usually taken into consideration
include road user costs, construction costs, maintenance costs, road
user benefits, and any disbenefits, which may include adverse
impacts due to dislocation of families, businesses, and so forth. The
results obtained from the economic evaluation of the feasible
routes provide valuable information to the decision maker.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 3. PRELIMINARY LOCATION SURVEY
ENVIRONMENTAL EVALUATION
Environmental evaluation includes the effect of road
construction to plants, animals, and human communities and
encompasses social, physical, natural, and man-made variables.
The construction of a highway at a given location may result in
significant changes in one or more variables, which in turn may
offset the equilibrium and result in significant adverse effects on
the environment that may lead to a reduction of the quality of life
of the animals and/or human communities.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 3. PRELIMINARY LOCATION SURVEY
ENVIRONMENTAL EVALUATION
In general, the requirements for the submission of environmental
impact statements for many projects includes:
Ø A detailed description of alternatives.
Ø The probable environmental impact, including the assessment of
positive and negative effects.
Ø An analysis of short-term impact as differentiated from long-term
impact.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 3. PRELIMINARY LOCATION SURVEY
ENVIRONMENTAL EVALUATION
Ø Any secondary effects, which may be in the form of changes in the
patterns of social and economic activities.
Ø Probable adverse environmental effects that cannot be avoided if
the project is constructed.
Ø Any irreversible and irretrievable resources that have been
committed.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 3. PRELIMINARY LOCATION SURVEY
In cases where an environmental impact study is required, it is
conducted at this stage to determine the environmental impact of
each alternative route. Such a study will determine the negative
and/or positive effects the highway facility will have on the
environment. Public hearings are also held at this stage to provide
an opportunity for constituents to give their views on the positive
and negative impacts of the proposed alternatives.
The best alternative, based on all the factors considered, is
then selected as the preliminary alignment of the highway.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 1. OFFICE STUDY OF EXISTING INFORMATION
Phase 2. RECONNAISSANCE SURVEY
Phase 3. PRELIMINARY LOCATION SURVEY
Phase 4. FINAL LOCATION SURVEY
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
The final location survey is a detailed layout of the selected
route. The horizontal and vertical alignments are determined,
and the positions of structures and drainage channels are located.
This survey serves the dual purpose of definitely fixing the
center line of the road, while at the same time physical data is
collected which is necessary for the preparation of plans for the
construction.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Pegging the Central Line Ø Property Lines
Ø Central Line Leveling Ø Intersecting Roads
Ø Cross Sections Ø Ditches & Streams
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Pegging the Central Line
Central line pegs are usually placed at every hundred feet
at all intersections and tangent points, and carried forward
continuously through curves and tangents.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Central Line Leveling
Profile levels are taken along the central line at each
station and at all intermediate points where there is any
significant change in slope of the ground, so that a truly
representative profile is obtained.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Cross Sections
Cross sections should be taken at each station, point of
significant change in ground slope and for a reasonable distance
beyond the beginning and end points of the projects.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Property Lines
The positions of all property corner lines, fences and other
man-made improvements are accurately determined and noted
down during the final location survey.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Intersecting Roads
The direction with respect to the pegged central line of all
intersecting roads should be measured. Profiles and cross
sections of the intersecting roads should be taken on both sides
of the new central line.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
STAGES OF FINAL LOCATION SURVEY
Ø Ditches and Streams
All ditches and streams within the area of construction
should be carefully located with respect to pegged central line.
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
The method is also used to set out the points of intersections
(PI) of the straight portions of the highway and fit a suitable
horizontal curve between these. This is usually a trial-and-error
process until, in the designer’s opinion, the best alignment is
obtained, taking both engineering and aesthetic factors into
consideration. Splines and curve templates are available that can
be used in this process.
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Phase 4.
FINAL LOCATION SURVEY
The spline is a flexible plastic
guide that can be bent into
different positions and is used
to lay out different curvilinear
alignments, from which the
most suitable is selected. It is
used first to obtain a hand-
fitted smooth curve that fits in
with the requirements of grade,
cross-sections, curvature, and Circular Curve Templates
drainage.
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Phase 4.
FINAL LOCATION SURVEY
Curve templates are
transparencies giving circular
curves, three-center compound
curves, and spiral curves of
different radii and different
standard scales. The hand-
fitted curve is then changed to
a more defined curve by using
the standard templates.
Centered Curve Templates
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PRINCIPLES OF HIGHWAY LOCATION
Phase 4. FINAL LOCATION SURVEY
The availability of computer-based techniques has significantly
enhanced this process since a proposed highway can be displayed
on a monitor, enabling the designer to have a driver’s eye view of
both the horizontal and vertical alignments of the road. The
designer can therefore change either or both alignments until the
best alignment is achieved.
Detailed design of the vertical and horizontal alignments is
then carried out to obtain both the deflection angles for horizontal
curves and the cuts or fills for vertical curves and straight sections
of the highway.
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PRINCIPLES OF HIGHWAY LOCATION
*RECREATIONAL AND SCENIC ROUTES
The location process of recreational and scenic routes follows the
same steps but the designer of these types of roads must be aware of
their primary purpose. For example, although it is essential for freeways
and arterial routes to be as direct as possible, a circuitous alignment
may be desirable for recreational and scenic routes to provide access to
recreational sites (such as lakes or campsites) or to provide special
scenic views. In designing such instances, it is important to adopt
adequate design standards.
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PRINCIPLES OF HIGHWAY LOCATION
Three additional factors should be considered in the location of
recreational and scenic routes:
1. Design speeds are usually low, and therefore special provisions should
be made to discourage fast driving, for example, by providing a
narrower lane width.
2. Location should be such that the conflict between the driver’s attention
on the road and the need to enjoy the scenic view is minimized. This
can be achieved by providing turn-outs with wide shoulders and
adequate turning space at regular intervals, or by providing only
straight alignments when the view is spectacular.
3. Location should be such that minimum disruption is caused to the area.
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Urban areas usually present complex conditions that must be
considered in the highway location process. In addition to the factors
under office study and reconnaissance survey, other factors that
significantly influence the location of highways in urban areas include:
Ø Connection to local streets
Ø Right-of-way acquisition
Ø Coordination of the highway system with other transportation
systems
Ø Adequate provisions for pedestrians
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Ø CONNECTION TO LOCAL STREETS
When the location of an expressway or urban freeway is being
planned, it is important that adequate thought be given to which
local streets should connect with on- and offramps to the
expressway or freeway. The main factor to consider is the existing
travel pattern in the area. The location should enhance the flow of
traffic on the local streets, and should provide for adequate sight
distances at all ramps. Ramps should not be placed at intervals
that will cause confusion or increase the crash potential on the
freeway or expressway.
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Ø RIGHT-OF-WAY ACQUISITION
One factor that significantly affects the location of highways in
urban areas is the cost of acquiring right of way. This cost is largely
dependent on the predominant land use in the right of way of the
proposed highway. Costs tend to be much higher in commercial
areas, and landowners in these areas are often unwilling to give up
their property for highway construction.
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Ø RIGHT-OF-WAY ACQUISITION (Cont.)
Thus, freeways and expressways in urban areas have been
placed on continuous elevated structures in order to avoid the
acquisition of rights of way and the disruption of commercial and
residential activities. This method of design has the advantage of
minimal interference with existing land-use activities, but it is
usually objected to by occupiers of adjacent land because of noise
or for aesthetic reasons. The elevated structures are also very
expensive to construct and therefore do not completely eliminate
the problem of high costs.
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Ø COORDINATION OF THE HIGHWAY SYSTEM WITH OTHER TRANSPORTATION
SYSTEMS
Urban planners understand the importance of a balanced transportation
system and strive toward providing a fully integrated system of highways and
public transportation. This integration should be taken into account during
the location process of an urban highway. Several approaches have been
considered, but the main objective is to provide new facilities that will
increase the overall level of service of the transportation system in the urban
area. Another form of transportation system integration is the multiple use of
rights of way by both highway and transit agencies. In this case, the right of
way is shared between them, and bus or rail facilities are constructed either in
the median or alongside the freeway.
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Ø ADEQUATE PROVISIONS FOR PEDESTRIANS
Providing adequate facilities for bicycles and pedestrians
should be an important factor in deciding the location of highways,
particularly for highways in urban areas. Pedestrians are an
integral part of any highway system but are more numerous in
urban areas than in rural areas. Bicycles are an alternate mode of
transportation that can help to reduce energy use and traffic
congestion.
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PRINCIPLES OF HIGHWAY LOCATION
*HIGHWAYS IN URBANIZED AREAS
Ø ADEQUATE PROVISIONS FOR PEDESTRIANS
Facilities for pedestrians should include sidewalks, crosswalks,
traffic-control features, curb cuts, and ramps for the handicapped.
Facilities for bicycles should include wide-curb lanes, bicycle paths
and shared-use paths.
In heavily congested urban areas, the need for grade-separated
facilities, such as overhead bridges and/or tunnels, may have a
significant effect on the final location of the highway. Although
vehicular traffic demands in urban areas are of primary concern in
deciding the location of highways in these areas.
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PRINCIPLES OF HIGHWAY LOCATION
*BRIDGE LOCATIONS
The general procedure for most highways, is to first determine the
best highway location and then determine the bridge site. In some cases,
such procedure results in skewed bridges, which are more expensive to
construct, or in locations where foundation problems exist. For such
occurring problems, all factors such as highway alignments, construction
costs of the bridge deck and its foundation, and construction costs of
bridge approaches should be considered in order to determine a
compromise route alignment that will give a suitable bridge site.
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PRINCIPLES OF HIGHWAY LOCATION
*BRIDGE LOCATIONS
A detailed report should be prepared for the bridge site selected to
determine whether there are any factors that make the site unacceptable.
This report should include accurate data on soil stratification, the engineering
properties of each soil stratum at the location, the crushing strength of
bedrock, and water levels in the channel or waterway.
When the waterway to be crossed requires a major bridge structure,
however, it is necessary to first identify a narrow section of the waterway
with suitable foundation conditions for the location of the bridge and then
determine acceptable highway alignments that cross the waterway at that
section. This will significantly reduce the cost of bridge construction in many
situations.
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HIGHWAY
SURVEY
METHODS
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HIGHWAY SURVEY METHODS
Highway surveying techniques have been revolutionized
due to the rapid development of electronic equipment and
computers. Surveying techniques can be grouped into three
general categories:
1. GROUND SURVEYS
2. REMOTE SENSING
3. COMPUTER GRAPHICS
Collectively, the entire process of selecting highway
locations, methods, and surveys is under the specialized field
of surveying termed as Route Surveying.
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HIGHWAY SURVEY METHODS
GROUND SURVEYS
The basic location technique for highways. The total
station is used for measuring angles in both vertical and
horizontal planes, distances, and changes in elevation through
the use of trigonometric levels, and the level is used for
measuring changes in elevation only.
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HIGHWAY SURVEY METHODS
REMOTE SENSING
The measurement of distances and elevations by using
devices located above the earth, such as airplanes or orbiting
satellites using Global Positioning Satellite systems (GPS). The
most commonly used remote-sensing method is
photogrammetry, which utilizes aerial photography thru aerial
surveying.
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HIGHWAY SURVEY METHODS
REMOTE SENSING
AERIAL SURVEYING
A highly technical and specialized work and are mostly
carried out by skilled, specially trained and experienced
personnel. Aerial surveys are usually consists of 4 parts; Flying,
Photography, Ground Control and Compilation of the Map.
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HIGHWAY SURVEY METHODS
REMOTE SENSING
PHOTOGRAMMETRY
The science of obtaining accurate and reliable information
through measurements and interpretation of photographs,
displaying this information in digital form and/or map form.
This process is fast and economical for large projects but can
be very expensive for small projects.
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HIGHWAY SURVEY METHODS
REMOTE SENSING (PHOTOGRAMMETRY)
The successful use of the method depends on the type of
terrain. Difficulties will arise when it is used for terrain with the
following characteristics:
Ø Areas of thick forest, such as tropical rain forests, that completely
cover the ground surface.
Ø Areas that contain deep canyons or tall buildings, which may
conceal the ground surface on the photographs.
Ø Areas that photograph as uniform shades, such as plains and
some deserts.
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HIGHWAY SURVEY METHODS
COMPUTER GRAPHICS
The combination of photogrammetry and computer
techniques. With the use of mapping software, line styles, and
feature tables, objects and photographic features can be
recorded digitally and stored in a computer file. This file can
then either be plotted out in map form or sent on to the
design unit.
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HIGHWAY SURVEY METHODS
COMPUTER GRAPHICS
A typical workstation is controlled by system software
that covers four main areas of design work:
Ø Preparatory work
Ø Photo Orientations and Aerotriangulation
Ø Data Transfer
Ø Plotting and Storage
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HIGHWAY SURVEY METHODS
COMPUTER GRAPHICS
The software for preparatory work is used for the input of
control point coordinates, input of camera calibration data,
and the selection of the needed image files.
The aerotriangulation software is used for automatically
locating fiducial marks (interior orientation), the removal of
bad parallax (relative orientation), scaling and leveling the
images (absolute orientation), and the creation of a control
mesh.
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HIGHWAY SURVEY METHODS
COMPUTER GRAPHICS
The data transfer programs store and check all data in
digital form in a MicroStation file for use by designers.
The fourth area is that of file storage and plotting
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PHOTOGRAMMETRY & SCALING
Photogrammetry is the
u s e o f p h o t o g ra p h s i n
mapping areas or
measuring distances. It is
relatively fast, but costly,
especially aerial or satellite
photogrammetry. It is very
efficient in mapping large
areas.
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PHOTOGRAMMETRY & SCALING
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PHOTOGRAMMETRY & SCALING
PHOTO SCALE
Thus,
Where,
X1 = dimension on the photograph
X2 = ground dimension
H = flying height above sea level
h = average elevation of the terrain with respect to the mean sea level.
f = focal length of the camera on the airplane
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PHOTOGRAMMETRY & SCALING
EXAMPLES
1. The scale on the map is 1:x. A lot having an area of 640sq.m. is represented
by an area of 25.6sq.cm on the map. What is the value of x?
2. Photographs are to be taken for preparing a highway design map. The lowest
elevation in the area to be photographed is 100 meters and the highest
elevation is 400m. The minimum photographic scale is to be 1:5000.
Determine the following:
a. What must be the flying height above sea level if the camera to be
used contains a lens with a focal length of 200mm?
b. What will be the maximum scale?
c. What is the average scale?
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HIGHWAY
SOILS &
EARTHWORKS
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HIGHWAY SOILS AND EARTHWORKS
HIGHWAY GRADES AND TERRAIN
One factor that significantly influences the selection of a
highway location is the terrain of the land, which in turn
affects the laying of the grade line. The primary factor that the
designer considers on laying the grade line is the amount of
earthwork that will be necessary for the selected grade line.
A method to reduce the amount of earthwork is to set the
grade line as closely as possible to the natural ground level in
order to have a balance between the excavated volume and
the volume of embankment. This method is done to obtain
the least overall cost in a highway/road project.
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HIGHWAY SOILS AND EARTHWORKS
HIGHWAY GRADES AND TERRAIN
Another factor that should be considered in laying the
grade line is the existence of fixed points, such as railway
crossings, intersections with other highways, and in some
cases existing bridges, which require that the grade be set to
meet them. When the route traverses flat or swampy areas,
the grade line must be set high enough above the water level
to facilitate proper drainage and to provide adequate cover to
the natural soil.
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HIGHWAY SOILS AND EARTHWORKS
EARTHWORKS
One of the major objectives in selecting a particular
location for a highway is to minimize the amount of earthwork
required for the project. Therefore, the estimation of the
amount of earthwork involved for each alternative location is
required at both the preliminary and final stages. To
determine the amount of earthwork involved for a given
grade line, cross sections are taken at regular intervals along
the grade line.
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HIGHWAY SOILS AND EARTHWORKS
EARTHWORKS
1. CROSS-SECTION METHOD
The method of plotting the existing cross-section
perpendicular to a particular line (usually the center line of a
proposed road) for the purpose of obtaining quantities such
as volumes.
It is usually done on linear construction projects such as
highways, railroads, and canals.
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LEVEL
CROSS-SECTION
(Equivalent Level or Trapezoidal Section)
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THREE LEVEL
CROSS-SECTION
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FIVE LEVEL
CROSS-SECTION
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END-AREA METHOD
PRISMOIDAL FORMULA
PRISMOIDAL CORRECTION
The prismoidal correction is the correction to be applied to the
volume using end-area method VE to make it equal to the volume
using prismoidal formula VP.
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CUT & FILL
SECTIONS
HIGHWAY SOILS AND EARTHWORKS
EARTHWORKS
2. BORROW-PIT METHOD
This method is used in estimating the volume of earth,
gravel, rock, or other material excavated or filled. It is also
known as the Unit-Area Method.
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ISOMETRIC VIEW TOP VIEW
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HIGHWAY SOILS AND EARTHWORKS
EARTHWORKS
3. BORROW-PIT METHOD
A mass-haul diagram or curve shows the cumulative
volumes (in cu.m.) in every section along the center line. It is
a series of connected lines that depicts the net accumulation
of cut or fill between any two stations.
The diagram is useful in planning the haulage of large
volumes or finding the overhaul charge of earthwork for the
linear construction projects such as highways.
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HIGHWAY SOILS AND EARTHWORKS
CHARACTERISTICS OF A MASS-HAUL DIAGRAM/CURVE
1. Rising or upward sloping sections of the mass curve indicates that
excavation is dominant, thus, the contractor has more earth
materials.
2. Falling or down sloping sections of the mass curve indicates that
there’s less excavation going o, more areas to be filled, thus, the
contractor has less earth materials.
3. The difference in ordinates between any two points indicate the
net cumulative volume.
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HIGHWAY SOILS AND EARTHWORKS
CHARACTERISTICS OF A MASS-HAUL DIAGRAM/CURVE
4. Any horizontal line drawn to intersect two points within the same
curve indicates a balance of excavation (cut) and embankment
(fill) quantities between the two stations.
5. The highest or lowest points of the mass-haul diagram
represents points where the proposed roadway coincides with
the natural ground level. It also represents points where the
roadway goes from cut to fill or vice versa.
CE 317 – HIGHWAY AND RAILROAD ENGINEERING 73
OVERHAUL DISTANCE
LIMITS OF ECONOMIC HAUL
WHERE:
L = overhaul distance (m)
Ch = cost per cubic meter/
meter station of overhaul
Cb = cost per cubic meter of
borrow or excavation
S = The length of each station
= usually taken as 20m
CE 317 – HIGHWAY AND RAILROAD ENGINEERING
NOTE:
1. The cost of disposing waste
material is considered as free.
2. The cost of haul (Ch) is often
expressed as cost per meter
station. If (Ch) is expressed in
cost per cubic meter. Disregard
(S)
CE 317 – HIGHWAY AND RAILROAD ENGINEERING
