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

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CHAPTER 7
Failures of
Formwork
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General Information
The failure of formwork is always embarrassing, expensive, and a
sad situation for everyone involved in a project. Safety must be a concern
of everyone, workers and supervisors. Accidents not only affect
the workers but also their families. Everyone in a project must be
alert to unsafe conditions, and all work must be performed in accordance
with safety regulations and the requirements specified in the
form design.
A failure may result in a collapse of part or all of the forms. Also
it may result in a distortion or movement of the forms that will require
the removal and replacement of a section of concrete. Sometimes
repairs, such as expensive chipping and grinding operations, may be
required to bring the section within the specified dimension limitations.
Such failures should not and will not occur if the formwork is
constructed with adequate strength and rigidity.
Formwork should be designed by an engineer or by someone
who has sufficient knowledge of forces and resistance of form materials.
Some states and cities require that forms, other than the simplest
concrete structures, be designed by registered professional engineers
and that following their erection they be inspected for adequacy by
an engineer.
Causes of Failures of Formwork
There are numerous causes of failures of formwork. Following is a
partial list:
1. Improper or inadequate shoring
2. Inadequate bracing of members
3. Lack of control of rate of concrete placement
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