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Building Design and Construction Handbook - Merritt - Ventech!

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STRUCTURAL STEEL CONSTRUCTION 7.15<br />

mensional requirements, will generally result in serviceable welds. As a result, most<br />

welding work incorporated in building construction, other than for major structures,<br />

is inspected using visual inspection techniques. The fabricator’s quality personnel<br />

are responsible for adherence to approved procedures. The owner’s inspector observed<br />

the erector’s operations <strong>and</strong> may perform any necessary visual inspection of<br />

the finished work.<br />

Four nondestructive testing methods are commonly used to evaluate welded<br />

work. These are (1) magnetic-particle inspection, (2) liquid penetrant inspection,<br />

(3) radiographic inspection, <strong>and</strong> (4) ultrasonic inspection. The latter two methods<br />

are the most common today. Each of these nondestructive testing methods add to<br />

the cost of construction <strong>and</strong> should be used where some special service requirement<br />

justifies this added feature. Any such testing must be identified on the drawings or<br />

in the specifications.<br />

7.3.7 Fastener Symbols<br />

Fasteners are indicated on design, shop, <strong>and</strong> field erection drawings by notes <strong>and</strong><br />

symbols. A simple note may suffice for bolts; for example: ‘‘ 7 ⁄8-in A325 bolts,<br />

except as noted.’’ Welds require more explicit information, since their location is<br />

not so obvious as that of holes for bolts.<br />

Symbols are st<strong>and</strong>ard throughout the industry. Figure 7.4 shows the symbols for<br />

bolts, Fig. 7.5 the symbols for welds. The welding symbols (Fig. 7.5a) together<br />

with the information key (Fig. 7.5b) are from the American Welding Society ‘‘Symbols<br />

for Welding <strong>and</strong> Nondestructive Testing, AWS A2.4.<br />

7.3.8 Erection Clearance for Fasteners<br />

All types of fasteners require clearances for proper installation in both shop <strong>and</strong><br />

field. Shop connections seldom are a problem, since each member can be easily<br />

manipulated for access. Field connections, however, require careful planning, because<br />

connections can be made only after all members to be connected are aligned<br />

FIGURE 7.4 Symbols for shop <strong>and</strong> field bolts.

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