what is the definition of formwork?
the total system of
support for freshly placed concrete,
including the mould or sheathing,
supporting members, hardware, and
necessary bracing, but excluding the
falsework
What is the definition of falsework?
any temporary
structure used to support a
permanent structure while it is not
self supporting.
what is the cost breakdown for a 24cm thick concrete wall?
what are the 2 main costs of formwork?
- Labor costs for formwork construction
– Productivity and number of uses
name the basic components of formwork along with brief sketch
what parameters influence fresh concrete pressure?
- Setting characteristics
– Rate of rise
– Consistency
– Pouring height
– Method of pouring and compaction
what are the 3 different concrete pressure loads?
what are the two types of formwork?
conventional and system formwork
what is conventional formwork?
Mainly handcrafted on site. Timber is basically used for the surface
and the scaffolding of the formwork. Metal parts function as supporters and fasteners.
what is system formwork?
less craftsmanship is necessary. The formwork gets constructed by using different types of prefabricated formwork components.
true or false, its common to see both conventional and system formwork at the same time?
true
what is the standard panel size for conventional formwork?
0.5 x 1.5m
what is two-faced formwork ties/anchors
To absorb the loads from the fresh concrete pressure,
tension ties/anchors are used for wall formwork.
- Tie: threaded ties
- Plastic or fiber-cement ducts; special design if water
tightness is required
what are typical formwork operations during the construction process?
- Slab – and beam formwork
- Wall formwork
- Column formwork
what is beam formwork?
The formwork for beams can be build
on top of slab formwork. Another
possibility is to use a trough shaped
rail system.
what are the the 3 common wall formwork types?
- The very flexible beam formwork –
mainly handcrafted. - Panel formwork – less
craftsmanship necessary because of
the use of prefabricated formwork
elements. - Circular formwork for
curved/rounded walls.
what is tunnel formwork?
- Tunnel forms are designed to cast walls and top slab at the
same time. They are ideally used for buildings with similar
sections. - Any change of the formwork system is expensive and should be avoided.
- The formwork can be moved by cranes or by itself (gantry)
while using an undercarriage.
when would the use of climbing formwork be used?
- For constructing high rise buildings or building components, it might be necessary to use special formwork and building procedures. For those occasions it is ordinary to use climbing forms. It is important to
distinguish between those forms that climb independently, and those that don’t. - While climbing formwork relies on “young” concrete to support it, it is very important to plan every step carefully. It is mandatory to
involve both structural design and concrete experts early on during job preparation.
what is self climbing formwork?
- Climbs independently from casting segment to casting segment by using hydraulic jacks, so the crane can be used for other operations.
- The working platforms are able to bear both, the load of material and working equipment. The work can go on in almost every
weather condition
what is slip or sliding formwork?
- Vertical progress: The formwork system is sliding continuously upwards. It is mounted onto climbing bolts and a yoke system. The
lifting device runs hydraulically or pneumatically. The finishing platforms completes the formwork system.
what is horizontal sliding formwork?
Horizontal progress : The sliding formwork follows a given line. This
procedure can exemplarily be used for curbs, gutters or concrete barriers.
list 5 items that you would need to consider before approving or disapproving the use of a concrete pump instead of bucket
- aggregate size
- workability
- cement content
- field practices
- pumping
