This document discusses the construction of a fly ash silo using advanced techniques such as pile foundation, slipform construction, and post-tensioning. It describes pile foundations as long reinforced concrete members driven into the ground to support large structures. For the fly ash silo foundation, 65 bored cast-in-place concrete piles were used. The document also explains slipforming as a technique using continuously moving formwork to construct tall, cylindrical structures like silos efficiently. Post-tensioning involves threading steel tendons through concrete after curing and tensioning them to strengthen the structure in tension. These advanced techniques allow for efficient, high quality construction of the large fly ash silo.

1. ADVANCEDINDUSTRIAL
CONSTRUCTION TECHNIQUE

2. Presented by
PRASANTH KUMAR DASU
M.N.SIRISHA
M.T.SULEKHA
T.JAYA RAM
Under the guidance of
Naomi Nischala.

3. WHAT IS FLY ASH SILO:
The fly ash silo is a massive
structure in cement plants,
which is used to store the fly ash
in that structure to add the
required amount of fly ash for
cement manufacturing by using
conveyers. Its is Generally
circular in shape. Capacity of
this silo is 40,000 tons.
OBJECTIVE:
CONTRUCTION OF FLY ASH SILO

4. CONSTRUCTION OF FLY ASH SILO BY USING
ADVANCED CONSTRUCTION
TECHNIQUE’S :
 PILE FOUNDATION
SLIP FORM TECHNIQUE
POST TENSIONING

5. WHAT IS PILE FOUNDATION:
Deep foundations are employed when the soil
strata immediately beneath the structure are not
capable of supporting the load with tolerable
settlement or adequate safety against any failure.
Pile foundations are relatively long, slender
members that are driven into the ground or cast-in-
situ.

6. TYPE OF FUNDATION USED PILE
FOUNDATION.

7. A VISUAL ABOUT PILE FONDATION:

8. Bored cast in situ pile:
Only concrete piles can be cast-in-situ. piles
can be cast-in-situ. Holes are drilled and these
are filled with
concrete. These may be straight-bored piles
or may be ‘under-reamed’ with one
or more bulbs at intervals. Reinforcements
may be used according to the
requirements.
Type of pile:

9. No. of piles
65 Nos.
LAYOUT OF PILES

10. DETAIL OF PILE FOUNDATION:
Specifications followed as per IS:456-2000
Diameter of pile- 1.0 meter.
Reinforcement used 25 dia. 8 nos.
Stirrup of 12mm dia spacing 200 mm c/c.
Depth of pile 23.5 meters.

11. Specifications followed as per IS:456-2000
Concrete grade used is M25 (1:1:2)
Grade of steel.Fe 500.
Cover maintained for main reinforcement 75 mm.
Pile is to be embeded into the hard strata atleast 150 to
300mm
.

12. SLIP FORM:
Its a Moving formwork.
 A Continuously Moving form Moving at such a speed , when concrete
is completed its initial setting time and after getting hardened. It will
withstand lateral pressure caused by jack rod, wind pressure etc.
TYPE OF FORM WORK

13. PRINCIPLE OF SLIPFORM
SLIPFORM MEANS A CONTINUOUSLY MOVING FORM
MOVING AT SUCH A SPEED BY USING THE
HYDRAULIC PRESSURE GIVEN GRADUALLY TO THE
FORM WORK UP TO DESIRED HEIGHT.THE WHOLE
FORM WORK WILL BE MOVED BY SUPPORTING ON
CLIMBING ROD OR JACK ROD.

14. TYPES OF SLIPFORM
1. STRAIGHT SLIPFORM.
2. TAPERED SLIPFORM.
3. SLIPFORM FOR SPECIAL APPLICATIONS.

15. Straight slipform
Silos
Chimneys (cylindrical)
Water towers
Central core for office blocks
Columns
Tapered slipform
Chimneys (conical)
Ventilation stacks
APPLICATION OF SLIPFORM

17. WORKABILITY REQUIRED
A. Easy compaction
B. To cover and protect the reinforcement.
C. To have less friction on formwork shutters.
• A film of mortar is created by compaction at
the contact with the form panel.
• This mortar film avoids micro - cracks during
slipform lifting.
D. Provide smooth surface to wall.

18. THE ABOVE FACTORS DEPEND ON
- QUALITY OF CEMENT.
- NATURE & SHAPE OF AGGREGATES.
- WATER CEMENT RATIO
- COMPACTION.
- HARDENING TEMPERATURE.
MINIMUM CONCRETE
STRENGTH FOR SLIPFORM

19. COMPONENT PARTS OF SLIPFORM

20. A VISUAL ABOUT SLIP
FORM

21. Slipform assembly at (-)2.00m level

22. OPERATION OF JACK.

23. Slipform jack operation

24. Exposed concrete surface finishing from slipform
platform

25. SILO UNDER PROGRESS

26. AT 30 METERS HEIGHT

27. MORE DETAILS ABOUT SILO
 DIAMETER OF SILO 22 METERS.
 WALL THICKNESS OF SILO 800 MM
UP TO 16.5 METERS.
 16.5 TO 57 MTS 350 MM THICK.
 INSERT PLATES FOR EQUIPMENTS
AND CONVEYORS FIXING.

28. • Accuracy
• Monolithic construction
• Lends itself to almost any shape in plan
• High quality surface finish
• Saves lot of workmanship.
• Saves staging materials
• Economical above a certain height.
• Produces aesthetically pleasing structures
ADVANTAGES OF SLIP FORM:

29. POST-TENSIONING
Introduction
What is post-tensioning?
Post-tensioning- is a method of reinforcing
(strengthening) concrete or other materials
with high-strength steel strands called
tendons.

30. O bje ctive :
Concrete is very strong in compression
but weak in tension, so as a tension
resistant member we provide tendons for
silo wall to strengthen the wall.

31. Structural elements that use post-tensioning:
Many types of bridges
Elevated slabs.
Foundations.
Walls and columns.
Silos and chimneys.

32. COMPONENTS
anchor
PT strand wedges

33. Methods and Materials
 PT strand - ASTM A416
– 7-wire treated carbon steel
– Min. TY (yield) = 52.74 kips
– Min. TU (breaking) = 58.60 kips
 Anchors - ACI code
– Guaranteed up to 95% of
the breaking strength TU.

34. Method of post-tensioning.
This is the
hydraulic jack
used for
tensioning

35. GRO UTING EQUIPMENT
Air Powered Grout Pump
Pumps cement grout only, no
sand. 32 Gallon Mixing Tank.
Mixes up to 2 sacks of material
at once and allows for grout to
be pumped during mixing or
mixed without pumping.

36. Detailed method of post-tensioning
 In slab-on-ground construction, unbonded
tendons are typically prefabricated at a
plant and delivered to the construction site,
ready to install.
 The tendons are laid out in the forms in
accordance with installation drawings that
are given.
 After the concrete is placed and has
reached its required strength, usually
between 3000 and 3500 psi (“pounds per
square inch”), the tendons are stressed and

37.  The tendons, like rubber bands, want to
return to their original length but are
prevented from doing so by the anchorages.
 The fact the tendons are kept in a
permanently stressed(elongated) state
causes a compressive force to act on the
concrete.
 The compression that results from the post-
tensioning counteracts the tensile forces
created by subsequent applied loading.
 This significantly increases the load-
carrying capacity of the concrete.

38.  Bonded post-tensioned concrete is the descriptive
term for a method of applying compression after
pouring concrete and the curing process (in situ).
 The concrete is cast around a plastic, steel or
aluminium curved duct, to follow the area where
otherwise tension would occur in the concrete
element.
 A set of tendons are fished through the duct and the
concrete is poured. Once the concrete has hardened,
the tendons are tensioned by hydraulic jacks.

39.  When the tendons have stretched sufficiently,
according to the design specifications they are
wedged in position and maintain tension after the
jacks are removed, transferring pressure to the
concrete.
 The duct is then grouted with cement to protect the
tendons from corrosion. This method is commonly
used to create homogeneity in load transmission.

40. ADVANTAGES OF POST-TENSIONINGADVANTAGES OF POST-TENSIONING
• Longer clear spansLonger clear spans
• Thinner slabsThinner slabs
• Lesser floor-to-floor heightsLesser floor-to-floor heights
• Shorter building heightShorter building height
• Lesser weightLesser weight
• Improved seismic performanceImproved seismic performance
• Faster construction cycleFaster construction cycle

41.  Post-tensioned
structures can be
designed to have
minimal deflection
and cracking, even
under full load.
 Post-tensioning
tendons, on the
other hand, are
considered “active”
reinforcing.

42. DISADVANTAGES OFDISADVANTAGES OF
POST-TENSIONINGPOST-TENSIONING
 The main disadvantage over post-
tensioning is the fact that a cable can
distress itself and burst out of the slab if
damaged (such as during repair on the
slab).

43. THANKYOU

44. ANY QUERIE’S?