CHAPTER 11
ELEMENTS OF SURVEYING AND
SURVEYING EQUIPMENT
This chapter provides an overview of survey-
ing in general with emphasis on the principles and
procedures of basic surveying and the use of
various surveying equipments, instruments, and
accessories. As an EA, you should realize that
accuracy in surveying is essential because other
factors affecting sound decisions in engineering
practice are dependent upon the results of your
survey.
Surveying is a science that deals with the
determination of the relative positions of points
on or near the earth’s surface. These points may
be needed to locate or lay out roads, airfields, and
structures of all kinds; they may be needed for
cultural, hydrographic, or terrain features for
mapping; and, in the military, these points may
be targets for artillery and mortar fires. The
relative horizontal positions of these points
are determined from distances and directions
measured in the field, while their vertical positions
are computed from the differences in elevations,
which are measured directly or indirectly from an
established point of reference or datum.
The earliest applications of surveying were for
the purpose of establishing the boundaries of land.
Although many surveyors are still preoccupied
with establishing or subdividing boundaries of
landed properties, the purposes of surveys have
branched out to many areas that parallel the
advancement of various engineering fields and
other areas of civilization. Surveyors may be
called upon in court to substantiate definite
locations of various objects, such as those
involving major traffic accidents, maritime
disasters, or even murder cases, in which direction
and distance have a bearing.
Surveying continues to play an extremely
important role in many branches of engineering.
The results of today’s surveys are being used to
map the earth above and below; for navigational
charts for use in the air, on land, and at sea;
and for other major survey operations for related
tasks in geology, forestry, archeology, and
landscape architecture. As a surveyor in the Naval
Construction Force, you will be required to
submit survey results before, during, and after
planning and construction of advanced base
structures,
bridges, roads,
drainage works,
pipelines, and other types of conventional ground
systems. In addition, an EA assigned to
an oceanographic unit may be involved in
hydrography to a great extent, establishing an
offshore triangulation network, depth sounding,
and mapping.
Again, though these surveys are for various
purposes, still the basic operations are the same—
they involve measurements and computations or,
basically, fieldwork and office work.
CLASSIFICATION OF SURVEYING
Generally, surveying is divided into two major
categories: plane and geodetic surveying.
PLANE SURVEYING
PLANE SURVEYING is a process of survey-
ing in which the portion of the earth being
surveyed is considered a plane. The term is used
to designate survey work in which the distances
or areas involved are small enough that the
curvature of the earth can be disregarded without
significant error. In general, the term plane
surveying is applied to surveys of land areas and
boundaries (land surveying) in which the areas are
of limited extent. For small areas, precise results
may be obtained with plane surveying methods,
but the accuracy and precision of such results will
decrease as the area surveyed increases in size. To
make computations in plane surveying, you will
use formulas of plane trigonometry, algebra, and
analytical geometry.
A great number of surveys are of the plane
surveying type. Surveys for the location and
construction of highways and roads, canals,
landing fields, and railroads are classified under
plane surveying. When it is realized that an arc
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