c. Stress Diagram. The stress diagram shows
the structural shape notations and welding symbols is
the main dimensions, the loadings, stresses, and sizes
primarily all that is necessary.
of the structural members.
a. Structural Member. The top chord is 1-ST
The foundation or
4 WF 8.5 x 16'-5 1/2". This means that there is one
d. Foundation Plan.
masonry plan (fig 2-39) covers the details of the
structural tee cut from a wide flange. The tee is 4
foundation, walls, piers, etc.
inches deep and weighs 8.5 pounds per foot. It is 16
feet 5 1/2 inches long. The bottom chord is the same
e. Erection Diagram. The erection diagram
type of member and is 30 feet 6 7/8 inches long and
(fig 2-40) shows the relative location of every part of
extends across the entire width of the truss. The
the structure and the assembly marks for the various
cross members are made from two angles 2" x 1 1.2"
members. The erection diagram may also include all
main dimensions, the number of pieces in the
members, the packing of pins, the size and grip of
b. Welding Symbols. Upon checking the
pins, and any special feature or information that may
welding symbols, you will discover that most of the
assist you in the field.
structural members will be fillet-welded with a fillet
having a 1/4-inch radius (thickness) on both sides and
f. Falsework Plan. Falsework is a temporary
running along the member for 4 inches. Looking at
support, usually timber, for a steel structure such as a
the upper-right of drawing (hip) we see the
truss bridge that cannot be self-supporting until
requirement for a bevel-groove weld of 1/4-inch
completed. Falsework plans are used only in a
radius on the other side of arrow.
g. Bill of Materials. The bill of materials
2-22. PRINTS OF PREFABRICATED
shows the different parts of the structure, identifying
marks, and shipping weight. This also serves as a
checkoff list to insure that you have the proper
a. In reading structural prints, whether for a
materials on hand.
complex structure or a prefabricated Quonset
assembly, the reading techniques are the same. Prints
The connection list
of prefabricated structures show how the various
h. Connection List.
provides the dimensions and the number of bolts,
parts are assembled. The prefabricated parts are
pins, and rivets required in the structure.
noted on the plans, elevations, and assembly
Figure 2-41 illustrates an exterior
i. List of Drawings. Since a great number of
elevation of a prefabricated aircraft maintenance and
drawings are required for any sizable structure, a
repair hangar. The CM notations shown in figure 2-
complete list of drawings is usually supplied with
41 mean corrugated metal panels.
each set of drawings for the structure. This list is in a
b. Illustrated in figure 2-42 is an assembly
drawing of a prefabricated, nailable steel frame
building (theater of operations modular). Note that
each part of the assembly is marked for identification
2-21. READING PRINTS OF STEEL
and location. For example, C5-4 designates a wall
corrugated sheet and J-20 a stringer. Figure 2-43 is a
A typical welded steel truss is illustrated in
detailed drawing showing how the framework is
figure 2-38. To read this print, the ability to interpret