For studying the actual construction of public or private works. (NOTE: As a construction
surveyor in the Army, this is the type of surveying you will conduct.)
On major operations with a higher order of accuracy that only government agencies are
equipped to handle; for example, hydrography and the proposed project to tie the world into
one triangulation network using earth-orbiting satellites.
Again, although these surveys are for various purposes, the basic operations are the same-they involve
measurements and computations or, basically, fieldwork and office work.
1-3. Duties of the Construction Surveyor. In support of construction activities, the surveyor obtains
reconnaissance and preliminary data that are necessary at the planning stage. During the construction
phase, the surveyor supports the effort as needed. Typical duties of the construction surveyor include-
Determining distances, areas, and angles.
Establishing reference points for both horizontal and vertical control.
Setting stakes or marking lines, grades, and principal points.
Determining profiles of the ground along given lines (centerlines and/or cross-section lines) to
provide data for cuts, fills, and earthwork volumes.
Laying out structures, culverts, and bridge lines.
Determining the vertical and horizontal placement of utilities.
1-4. Relative Location and Position. The location of a point on the earth can only be described in
terms of the relative location or position of the point with reference to another point. This relative
location or position of a point on the earth's surface and the corresponding point on a map may be
described in terms of a system of coordinates. Coordinates are quantities that designate the position of a
point in relation to a given reference frame. Telling someone that the Main post exchange (PX) is two
blocks north of Main Street and three blocks east of Broadway is using coordinates. A point may also
be identified by its latitude and longitude and its distance and direction from another point.
a. Coordinates. Coordinates are often used with a grid, which is a network of uniformly spaced
straight lines intersecting at right angles. Figure 1-1, page 1-4, shows a grid. The reference frame
consists of horizontal and vertical baselines. Each baseline in this example is divided into units of
measurement, and each unit is further divided into tenths. The direction of the vertical baseline is called
north, and the direction of the horizontal baseline is called east. The intersection of the baselines is
called the origin and has a coordinate value of zero-zero. The dot is located 2 units plus three-tenths of a
unit more, or 2.3 units, above the horizontal baseline. The dot is also 1.1 units east of the vertical
baseline. The coordinates of this grid is 2.3 north and 1.1 east.
1-3
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