This ppt is about quality aspects of construction materials for substructure of simhadri power plant

1. Quality Aspects of Construction
Materials for Substructure of Simhadri
Power Plant
SUBMITTED BY:-
V. VINAY RAVI KUMAR (A13559016060)
S. JYOTHISH KUMAR (A13559016065)
B. LAKSHMI GANAPATHI (A13559016097)
AKHIL GEORGE (A13559016141)
P. SAI SITARAM (A13559016122)

2. Introduction
Location – Vishakhapatnam, Andhra Pradesh
Owner – NTPC Limited
Capacity – 2000 MW
Coal Source – Kalinga Block of Talcher Coal fields in Orissa
Water Source – Yeluru Canal for fresh Water which turns the
turbine, Sea Water for cooling purpose

3. Foundation Details
 Track Hopper - Raft with Heavy Beams
 Conveyor - Normal Individual Footings
 Crusher House - Raft foundation
 Boilers - Normal Foundation but with HRC
 Cooling Towers - Piling with Raft
 Turbo Generator - Table top foundation
 Chimney - Pile foundation

4. Coal storage
 In coal-fired power stations, the raw coal from the coal storage area is first
crushed into small pieces and then conveyed to the coal feed hoppers at the
boilers.
 The coal is next broken into a very fine powder called Coal Dust, so that coal will
undergo complete combustion during combustion process.
 A raft foundation of 1.5 meters thickness is provided for Coal Bunkers.
 The coal bunkers has a capacity of approx. 20 to 30 days of coal supply needed
for the power plant.

5. Boiler
 The foundation provided under the boiler is also
Raft foundation but made with HRC
 At higher temperatures (above about 800 degrees
F), high-heat-resistant concrete is generally needed.
 Calcium aluminate cement is used for making a
Heat-resistant concrete.
 The most important factor considered for making
HRC is the selection of aggregate.
 Light-weight aggregates is mainly used in HRC

6. Cooling Towers
 Bentonite
 Density (fresh Bentonite) - between 1.03 to 1.10
 Density While boring - <1.25
 Density before Concreting - <1.12
 Concreting
Tremie Method
 Concrete
 Min. Cement Content is 370 kg/ Cu.m
 Slump 150 mm – 180 mm
 Aggregate size not more than 20 mm
 After Piling a raft is casted connecting all the pile

7. Turbo Generator
 The turbo-generator foundation consists of
turbo-generator and its auxiliaries mounted
on a table top foundation
 Can be made of steel or RCC
 The top deck, column and bottom raft
together make up the foundation.
 Sometimes the turbo generator foundation is
mounted on vibration isolator

8. CHIMNEY FOUNDATION
• Generally circular raft foundations are provided
• Pile foundations are also common.
• Diameter and thickness of raft foundation is
governed by combined vertical loads and
wind/seismic loads.
• Generally for a 220m tall chimney, in wind
speeds upto about 40 m/sec, would require a 30 m
diameter raft * 3m thickness, the height of this
Chimney is 275m a record in Asia for being the
tallest factory chimney

9. I.S. CODES
 IS: 456 – code of practice for plain and reinforced concrete.
 IS: 383 – specifications for fine & coarse aggregate from natural sources for
concrete.
 IS: 2386 – methods of tests for aggregate for concrete.
 IS: 2430 – methods of sampling.
 IS: 4082 – specifications for storage of materials.
 IS: 2116 – permissible clay, silt & fine dust contents in sand.
 IS: 3495 – methods of testing of bricks.
 IS: 3025 – tests on water samples.

10. Quality of Materials
 Soil
 Concrete
 Fine Aggregate
 Course Aggregate
 Cement

11. GEOTECHNICAL INVESTIGATON
REPORT
To design substructure for the proposed structure, adequate information
regarding the sub soil conditions is required. For this purpose, a
detailed geotechnical investigation has been undertaken at the site of
the proposed structure.
OBJECTIVE OF INVESTIGATIONS:
For designing the foundation system of the proposed structure, the
following data are required:
 Type of foundation
 Depth below the ground level at which the foundation system is to
be laid
 Allowable Bearing pressure at the foundation level

12. SOIL BEARING CAPACITY
 Plate Load Test
 Penetration Test
PLATE LOAD TEST:
 This is a field test for determining the ultimate bearing capacity soil
and the likely settlement due to given loading.
 The test consist of loading a steel plate at foundation level and the
settlement due to each load increment are recorded.
 Thus the ultimate bearing capacity of soil is obtained by dividing the
total load on the plate.

13. FIELD INVESTIGATIONS
Various tests are carried out at site:
 Conducting Borehole test
 Recording ground water table levels
IS Codes:
IS 1892-1979: Code of practice for sub surface investigations for foundations
IS 2131:1981: Method of standard penetration test for soils

14. Chemical Analysis
 A water and a soil sample collected from boreholes, have been
tested to determine the pH value and the presence of salts harmful
to reinforced cement concrete construction namely chloride and
sulphate contents
IS Limits:
Ph Value not less than 6
Chloride content(ppm): Maximum 500ppm
Sulphate content: Maximum 400ppm
IS 2720:1987: Methods of test for soils: Determination of Ph Value

15. Parameters for Concrete
Activity:
 Design of Concrete Mix
 Calibration of Batching Plant
 Batching of Materials
 Sampling
Tests on Concrete:
 Workability(Slump test)
 Compressive Strength

16. Parameters for Fine Aggregate
Activity:
 Pre-qualification of source
 Procurement
 Storage
 Sampling
Tests:
 Gradation
 Soundness
 Specific Gravity
 Water Absorption
 Moisture Content
 Silt Content

17. Coarse Aggregate
Activity
 Pre-qualification of source
 Procurement
 Storage
 Sampling
Tests:
 Gradation
 Flakiness Index
 Elongation Index
 Aggregate Impact Value
 Abrasion Value
 Crushing Value
 Soundness
 Specific Gravity & Density

18. Tests for Aggregates with IS codes
Property of
Aggregate
Type of Test Test Method
Crushing strength Crushing test IS : 2386 (part 4)
Hardness
Los Angeles abrasion
test
IS : 2386 (Part 5)
Toughness Aggregate impact test IS : 2386 (Part 4)
Durability Soundness test IS : 2386 (Part 5)
Shape factors Shape test IS : 2386 (Part 1)
Specific gravity,
porosity
Specific gravity test
and water absorption
test
IS : 2386 (Part 3)

19. Parameters for Cement
Activities:
 Pre-qualification of source
 Procurement
 Storage
 Sampling
Tests:
Initial & Final Setting Time
Compressive Strength
Soundness
Fineness(Sieve Method)

20. Property of cement Type of test
Fineness IS: 4031 (Part 1)
Soundness IS: 4031 (Part 3)
Compressive strength IS: 4031
Intial & Final setting time IS: 4031 (Part 5)

21. THANK YOU