modern technique of framework

1. PRESENTED BY :
RAHUL BHARDWAJ
B. ARCH 7TH SEM
NIMS SCHOOL OF
ARCHITECTURE AND
PLANNING

2. i. process efficiency
ii. Safety
iii. Sustainability features
iv. Consideration
i. Introduction
ii. Procedure
iii. Types of slip form
iv. Advantage
v. Precautions
vi. Application of slip form

3. INTRODUCTION
• Slip form construction, or
continuously formed
construction, is a construction
method in which concrete is
poured into a continuously
moving form.
• Basically, this method involves
the continuous placing of
concrete in a shallow mould
having the same plan as the
building to be constructed. This
rigid mould, or "slip-form" as it
is called, forms the working
deck which is jacked slowly
upwards at a controlled rate
until the required elevation is
reached.

4. INTRODUCTION:
•Method of vertically extruding a reinforced
concrete section and is suitable for
construction of core walls in high-rise
structures – lift shafts, stair shafts, towers.
•The formwork rises continuously, at a rate of
about 300 mm per hour, supporting itself on
the core and not relying on support or access
from other parts of the building or permanent
works.
•Allows for the continuous pouring of concrete
into walls of a structure and only stops when
the full required height of the structure has
been reached.
•The height of the formwork is designed in
such a way that while the top of the formwork
is being filled by concrete the lowest layer of
concrete poured earlier has already gained an
initial set. When the formwork is moved
upwards the concrete that is then exposed
remains firm. CHEUNG KONG
CENTRE
2-SLIPFORMTECHNOLOGY

5. PROCEDURE :
•Assembly can only start once the foundations
are in place and the wall starter is in correct
alignment.
•Slip form shuttering is aligned with the help of
yokes.
•Horizontal crossbeams connect these yokes.
•Hydraulic jacks are attached to these
crossbeams for simultaneous upward movement.
•Height of the slip form ranges from 1.1 to 1.5
meters.
•Yokes and crossbeams also used to support the
working platform.
•Structure should be rigid and shape maintained
at all times.
•Make sure there is no lag or else it prevents the
structure from free upward movement
• It is also possible to reduce wall thicknesses
as the construction gains height and
arrangements have to be made in the slip form
structure that will enable such reduction at
regular intervals.

6. 1-VERTICAL SLIP-FORM
In vertical slip forming, the
concrete form may be
surrounded by a platform on
which workers stand, placing
steel reinforcing rods into the
concrete and ensuring a
smooth pour. Together, the
concrete form and working
platform are raised by means
of hydraulic jacks. Generally,
the slip-form rises at a rate
which permits the concrete to
harden by the time it emerges
from the bottom of the form.
TYPES OF SLIP-FORM CONSTRUCTION

7. 2- HORIZONTAL SLIP-FORM
In horizontal slip forming for pavement
and traffic separation walls, concrete is
cast, vibrated, worked, and settled in
place while the form itself slowly moves
ahead. This method was initially
devised and utilized in Interstate
Highway construction initiated during
the 1950s.

8. •Slip form methods of construction can also be adapted to horizontal structures and are used for
paving, canals, and tunneling.
• The technique is more in use for structures that have continuous walls like silos , chimneys, and
piers for very tall bridges.
• It has also been successfully used for construction of buildings, although this requires the
manner of leaving inserts for openings like doors and windows to be decided well in advance, as
well as also any necessary inserts to support floor slabs after the walls are constructed.
HORIZONTAL SLIP FORM :

9. 3-TAPERED SLIP-FORMING
Slip-forming is also used in the construction
of conical chimneys, cooling towers, piers
and other tall concrete structures involving
constant or changing thicknesses in walls,
diameters and/or shapes. A form is used
with sections which overlap so that one
gradually slides over the other. This is
commonly done in chimney construction but
it is not satisfactory for architectural
concrete because the lap shows. While the
tapered slip-forming process is similar to
that used on the standard slip-forming, it
requires greater attention, contractor
experience and expertise ensures the
success of such projects.

10. ADVANTAGES:
•A major cost of concrete structure
construction is the required formwork to retain
the concrete till it can be safely de-shuttered
and be able to support itself and other
imposed loads.
•The formwork needs to be continually
removed to newer locations and then re-
erected.
•Continuous use of manpower and lifting
equipment like cranes.
• In the case of slip form building, the
formwork is erected only once and remains
intact until the entire structure is completed.
•Great reduction in the cost of formwork as
well as time saving for re-erection.
•Cost effective
•The reduction in the movement of formwork
and workers also leads to far more safe
working conditions that also make it a major
advantage.

11. PRECAUTIONS
• Concrete is continuously protected against
loss of moisture and rapid temperature
changes for 7 days
• Unhardened concrete is protected from rain
and flowing water
• Prevent plastic shrinkage
• Plastic cracks are filled by injection of epoxy
resin.

12. APPLICATIONS OF SLIP-FORM
CONSTRUCTION
Slip-form construction is used for tall structures,
such as towers, buildings, and dams, as well as
horizontal structures, such as roadway barriers. It
enables continuous, non-interrupted, cast-in-place
joint-less concrete structures which have superior
performance characteristics over construction
methods using discrete form elements. Slip
forming relies on the quick setting properties of
concrete, and requires a balance between quick-
setting capacity and workability.
Capital Gate Tower,
Abu Dhabi
King Abdul-Aziz Airport Inn Canal, Germany

13. 3-JUMP FORM:
 Generally, jump form systems
comprise the formwork and
working platforms for
cleaning/fixing of the
formwork, steel fixing and
concreting.
 Jump form, often described as
climbing form. It is suitable for
construction of multi-floor
vertical concrete elements in
high-rise structures, such as
shear walls, core walls, lift
shafts, stair shafts and bridge
pylons.
 It is a highly productive system
designed to increase speed and
efficiency while minimizing
labor and time.

14. PROCESS EFFICIENCY :
 Fast construction can be achieved by
careful planning of the construction
process. Crane availability is critical for
normal jump form.
 Self-climbing formwork cuts down the
requirement for crane time
considerably. By allowing the crane to
be used for other construction work this
may reduce the total number of cranes
needed on site.
 The formwork is independently
supported, so the shear walls and core
walls can be completed ahead of the
rest of the main building structure. This
can help to provide stability to the main
structure during its construction and
can have the beneficial effect of taking
the jump form core off the project
critical path.

15. SAFETY :
 Working platforms, guard rails, and ladders
are built into the completed units of market-
leading formwork systems. Complete wind-
shield protection on platform edges is also
possible.
 Self-climbing formwork systems are provided
with integral free-fall braking devices.
 The completed formwork assembly is robust
and provides a stable working platform.
 The reduced use of scaffolding and temporary
work platforms results in less congestion on
site.
 The setting rate of concrete in those parts of
the structure supporting the form is critical in
determining the rate at which construction can
safely proceed.
 The repetitive nature of the work means that
site operatives can quickly become familiar
with health and safety aspects of their job.
Formwork suppliers provide materials and
resources to help train the labour force.

16. SUSTAINABILITY FEATURES :
 The formwork system is easy to
clean and reuse with little formwork
waste generated compared to
traditional formwork.
 Climbing formwork systems offer
simplicity, safety and cost
effectiveness for certain high-rise
building structures.
 The repetitive nature of the work,
combined with the engineered nature
of the formwork, allows fine tuning of
the construction operations, which in
turn leads to minimal concrete
wastage.
 Many repeated uses of formwork are
possible before maintenance or
replacement is needed, the number
of uses depending on the quality of
the surface finish of concrete
specified.

17. SUMMARY
• Slip form construction is a construction method
in which concrete is poured into a continuously
moving form.
• There are two types of slip-forms; vertical and
horizontal.
• Slip-form construction consumes very less
time but requires careful planning of
construction process to achieve high production
rates.
• Due to continuous concrete pouring in slip-
form construction it produces better concrete
joint less and watertight structures.
• Slip form systems require a few but highly
skilled workforce.
• Slip-forming is also used in the construction of
tapered structures involving changing
thicknesses in walls, diameters and/or shapes.

18. REFFERENCE
• WIKIPEDIA.ORG
• SLIDESHARE.NET
• THECONSTRUCTOR.ORG
• WWW.CONCRETECENTRE.COM
• fac.ksu.edu.sa/sites/default/files/7-_slip-form_construction.pdf