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

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Failures of Formwork 193
on the decking or shoring system, all form members should be connected
together in a manner that will prevent the members from separating
or moving with respect to each other.
Design of Formwork to Withstand Dynamic Forces
The analyses presented in the previous sections of this chapter show
that formwork may be subjected to dynamic forces in addition to
those resulting from static loads. The magnitudes of dynamic forces
on formwork will depend on the methods of placing the concrete.
When these types of forces are anticipated, the strength and rigidity
of the formwork should be increased adequately by additional bracing,
increased strength of the form material, and stronger connections
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between adjoining members.
Examples of Failure of Formwork and Falsework
The following examples briefly describe several failures of formwork
and falsework during the erection of concrete bridges. This information
is presented to emphasize the need to exercise care in designing,
erecting, using, and removing formwork or falsework for concrete
structures.
Canada Larga Road Bridge: During the construction of this 88-ftlong
structure, a falsework frame collapsed as it was being adjusted
to grade, causing several injuries and a substantial delay in the completion
of the project (see Figure 7-2).
Oceanside Bridge: The span for this bridge, a 127-ft-long box girder,
had been poured, and the forms had been removed with only the
FIGURE 7-2 This falsework collapsed while being adjusted to grade.
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