Formwork for Concrete Structures by R.L.Peurifoy and G.D- By EasyEngineering.net

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Forms for Concrete Bridge Decks 437
Dimension A
(equals flange with plus 3 /4'')
Top of concrete
–13 Coil nut
Plywood deck
Type 4 press-steel
Hanger
2" minimum
Joist
Double
ledgers
B-14 coil B-11 flat washer
bolt
FIGURE 16-3 Coil rod hanger for bridge decks suspended from steel beams.
(Source: Dayton Superior Corporation)
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For this particular condition, the calculated approximate deflection
of 0.14 in. using an equivalent uniformly distributed load is slightly
higher than the calculated 0.12 in. deflection using the four concentrated
loads.
Hanger to Support Stringer
The coil bolt hanger that rests on the top flange of the steel beam must
have adequate strength to hold the 2,916-lb load from the ends of the
double stringers. The safe working load of the coil rod hanger assemblies
generally ranges from 2,000 to 6,000 lb. For this example, a 3,000-lb
hanger will be required.
Figure 16-3 shows the details of a coil bolt hanger that is available
for forming bridge decks. The hanger rests on the top flange of the
steel beam and is to be used with full bearing under the end sections.
There should be a careful check of the exact beam size before ordering
hangers because steel beams are often oversize and concrete beams
are often undersize.
Coil bolt hangers provide adjustment quickly and easily from the
top of the formwork. These hangers consist of specially formed stamped
steel end sections electrically welded to each end of a connecting strut.
Both adjustable coil bolt assemblies and fixed-length coil bolt assemblies
are available.
Wood Forms for Deck Slab with Haunches
Coil rod hangers are available for hanging formwork from structural
steel beams with haunches of any height. These hangers are designed
to break back inside the concrete. Breakback is accomplished by placing
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