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Steel formwork
1. STEEL
FORMWORK
Construction Technology iv
MOHD SUFIAN ABDUL RAHIM 2010536105
HIDAYAT BIN ZAMRI 2010108475
MUHAMMAD REDZUAN BIN ZULKIFLI 2010344265
MUSAHIDDIN BIN MD ZAINAL 2010740055
XYFUL QAREEM ALZIFF BIN RIZUWAN 2010124671
2. Formworks• Forms are molds to receive concrete in its’ plastic form.
• Formwork is temporary structure, as such, it is not
normally shown on the drawings.
Formwork for Beams and Slabs
3. Definition
• Its is an artificial support provided below and around the
precast or cast in situ concrete work.
• Formwork is commonly made of
• Steel
• wood
• Formwork construction & casting is of prime importance
in concrete industry. It share a significant amount of
concrete cost.
4. Qualities of formwork
• It should be water tight
• It should be strong
• It can be reusable
• Its contact surface should be uniform
• It should be according to the size of member.
5. Types of formwork
• Formwork are mainly of two types
• Steel formwork
• Wooden formwork
• Steel formwork is made of
• Steel sheets
• Angle Iron
• Tee Iron
• Wooden formwork consists of
• Props
• Planks battens
• Ledgers
• sheeting
6. • Temporary Structure
- Temporary structure required to safely support concrete
until it reaches adequate strength.
• Permanent Structure
-Permanent formwork remains in situ for the life of the
building
7. Steel Formwork
• This consist of panels fabricated out of thin steel plates
stiffened along the edges by small steel angles.
• The panel units can be held together through the use of suitable
clamps or bolts and nuts.
• The panels can be fabricated in large number in any desired
modular shape or size.
• Steel forms are largely used in large projects or in situation
where large number reuses of the shuttering is possible.
• This type of shuttering is considered most suitable for circular
or curved structures.
8. • For heavy concrete work
• With reasonable care will last indefinitely
• High initial cost and high handling cost
9. The first floor circular columns were constructed using steel
column forms. The steel column form should be oiled before
concreting.
10. After concreting to the first floor columns, the steel column forms
were dismantled easily.
12. Compared with timber
formwork
• Steel forms are stronger, durable and have longer life than
timber formwork and their reuses are more in number.
• Steel forms can be installed and dismantled with greater
ease and speed.
• The quality of exposed concrete surface by using steel
forms is good and such surfaces need no further
treatment.
• Steel formwork does not absorb moisture from concrete.
• Steel formwork does not shrink or warp.
13. STEEL FORMWORK AND
ACCESSORIES
• Steel formwork systems for every size and shape of
ground plan, in practical dimension & equipped with
different features to make shuttering more efficient.
14. Flatform Panels Form Work
Column Formwork
Application of Push-pull Prop. &
Soldier System
15.
16. Flat Form
Flat Form is used for forming planes such as those of Square columns,
walls, slab floors, etc. By combining units of various sizes, flat form
can be made to serve a wide variety of purposes.
17. Corner Angle Outside Corner Form
Inside Corner Form "L" - type pin & U-clip
Steel Form for Corners
Form can be assembled easily and tightly by using the Corner Angle,
Outside Corner Form & Inside Corner Form.
We can tailor-made various sizes of corner to suit customer specific
requirements & application.
18. Samples of Box Culvert Design
A combination of the Flat form Panels & corners are illustrated in the
application of common Box Culvert.
Versatile : complete systems made to meet the needs of contractors;
Easy to Use : quick assembly & fixing
Proven Design : fabricated for tough working conditions
19. Removal of formwork
• Time of formwork removal depends on the
following factors
1. Type of Cement
Rapid hardening cements require lesser time as compared to
OPC (Ordinary Portland Cement)
2. Ratio of concrete mix
Rich ratio concrete gain strength earlier as compared to weak
ratio concrete.
3. Weather condition
Hydration process accelerates in hot weather conditions as
compared to cold and humid weather conditions.
20. Time of Removal of formwork
Sr.
No Structural Member
OPC
(Ordinary Portland Cement)
Rapid Hardening
Cement
1 Beam sides, walls & Columns 2-3 Days 2 Days
2 Slab (Vertical Supports remains intact) 4 Days 3 Days
3 Slab (Complete Formwork removal) 10 Days 5 Days
4 Beams (Removal of Sheeting, Props
remains intact)
8 Days 5 Days
5 Beams & Arches (Complete formwork
removal) (up to 6 m span)
14 Days 5-8 Days
6 Beams & Arches (Complete formwork
removal) (more than 6 m span)
21 Days 8-10 Days
21. Maintenance of
formwork
• Due to continuous use wooden planks & steel plates
surfaces become uneven and require maintenance.
• For wooden formwork use cardboard or plastic fiber
board. Bolt hole places must also be repaired.
• For steel formwork plates must be leveled by mallet and
loose corners must be welded.
22. Advantages of
steel formwork
• It can be used for a no. of times.
• It is non absorbent.
• Smooth finish surface obtained.
• No shrinkage of formwork occurs.
• Easy to use.
• Its volume is less
• Its strength is more.
23. Disadvantages of
steel formwork
• Limited size or shape
• Excessive loss of heat
• A very smooth surface will be produced which would
give problems for finishing process
• Limited fixing