advanced concrete technology

2. High Density Concrete
 High Density=Heavyweight
 Density should be more than 2600 kg/m3
 Dens CRETE
 Offers more strength
 Can be used everywhere, in all construction practices
 Resistant to extreme weather

3. Main Components:
 Cement
--- Provides limited strength
--- Not that useful in high density concrete
--- Used as binding material
Water
Aggregates
Admixtures

4. Natural Aggregates
•Aggregates
are obtained from iron ores
•Large amount of iron content
•Varying densities so variety of high density concrete can be produced
Types:
1.
2.
4.
3.

5. Man-made (Synthetic) Aggregates:
Iron Shots
Chilcon
Synthetic
Aggregates
Fergran
Lead Shots

6. Admixture:
 Water reducing admixture is used
 Consists Lignosulfonic acid, carboxylic acids
 Use of Water reducing admixture in high density concrete
–Increase workability
–Reduces water requirement
–Reduces cement content requirement
–High early strength

7. Application:
 High density radiation shielding
 Precast blocks
 Mass concrete projects
 High density concrete applications columns
 Gravity seawall, coastal protection & breakwater
structures
 Bridge counterweights
 Ballast for ocean vessels
 Off shore platforms noise and vibration dampening

8. Advantages:
 High neutron and gamma ray attenuation
 Good mechanical properties
 Relatively low initial and maintenance cost
 Easy to construct
Disadvantages:
Space
Weight

9. Production:

10. High Strength Concrete:

Using Type I Portland cement, gravel or crushed limestone coarse
aggregate, sand from a local deposit, and for some mixes a waterreducing retarding admixture.
 Water-cement ratios ranged from 0.70 to 0.32
 Concrete strength of 90-120 MPa
 Uniaxial compressive strengths ranged from about 21 to 76 MPa.
 Pertaining to compressive strength, strength gain with age, specimen
size effect, effects of drying, stress-strain curves, static modulus of
elasticity, Poisson’s ratio, modulus of ruptuie, and split cylinder strength.
 Has to take care about mix proportioning, shape of aggregates, use of
supplementary cementitious materials, silica fume and super
plasticizers.

11. Special methods of making high strength concrete
 Seeding: This involves adding a small percentage of finely ground, fully
hydrated Portland cement to the fresh concrete mix.
This method may not hold much promise.
 Revibration: Controlled revibration removes all the defects like
bleeding, water accumulates , plastic shrinkage, continuous capillary
channels and increases the strength of concrete.
 High speed slurry mixing: This process involves the advance
preparation of cement - water mixture which is then blended with
aggregate to produce concrete.
 Use of admixtures: Use of water reducing agents are known to
produce increased compressive strength.

12.  Inhibition of cracks: If the propagation of cracks is inhibited, the
strength will be higher.
Concrete cubes made this way have yielded strength up to 105MPa.
 Sulphur Impregnation: Satisfactory high strength concrete have
been produced by impregnating low strength porous concrete by
sulphur.
The sulphur infiltrated concrete has given strength up to 58MPa.
 Use of Cementitious aggregates: Cement fondu is kind of clinker.
Using Alag as aggregate, strength up to 25MPa has been obtained with
water cement ratio 0.32.

13. Fire resistance of High Strength Concrete:

14. Strength-weight ratio becomes comparable
to steel:
Strength-Weight Ratio
45
40
35
30
25
20
15
10
5
0
Structural steel
Concrete
High strength
concrete
Lightweight HSC

15. High-strength concrete is often used in bridges

16. HIGH PERFOMANCE CONCRETE:
“A high performance concrete is a concrete in which certain
characteristics are developed for a particular application and
environments”:











Ease of placement
Compaction without segregation
Early-age strength
Long term mechanical properties
Permeability
Durability
Heat of hydration
Toughness
Volume stability
Long life in severe environments
High resistance to frost and deicer scaling damage
 Toughness and impact resistance
 Volume stability

17. High-performance concrete is often used in
bridges and tall buildings

18. Materials Used in High-Performance Concrete
Material
Primary contribution/Desired property
Portland cement
Cementing material/durability
Blended cement
Cementing material/durability/high strength
Fly ash
Cementing material/durability/high strength
Slag
Cementing material/durability/high strength
Silica fume
Cementing material/durability/high strength
Calcined clay
Cementing material/durability/high strength
Metakaolin
Cementing material/durability/high strength
Calcined shale
Cementing material/durability/high strength

19. Super plasticizers
Flow ability
High-range water reducers
Reduce water to cement ratio
Hydration control admixtures
Control setting
Retarders
Control setting
Accelerators
Accelerate setting
Corrosion inhibitors
Control steel corrosion
Water reducers
Reduce cement and water content
Shrinkage reducers
Reduce shrinkage
ASR inhibitors
Control alkali-silica reactivity
Polymer/latex modifiers
Durability
Optimally graded aggregate
Improve workability and reduce paste

20. The required durability characteristics are governed by
the application of concrete and by conditions expected to
be encountered at the time of placement. These
characteristics should be listed.
Environment
Environment
Concrete
Impact
Resistance
Durable
Concrete
(HPC)
Deterioration
Concrete

21. REFERANCE:
Publication:Journal Proceedings Author(s):Ramon L. Carrasquilio, Arthur H.
Nilson, and Floyd 0. Slate
CSTR49: „Design guidance for high strength concrete‟, Concrete Society Technical
Report No. 49, The Concrete Society, 1998
CEB-FIP Model code for concrete structures, 1990. Comité Euro-International du
Beton. Thomas Telford, London, 1993. Bulletin d‟Information No. 213/214. 437 pp.
BRITISH STANDARDS INSTITUTION. BS 8110 Structural use of concrete Part 3:
1985. Design charts for singly reinforced beams, doubly reinforced beams and
rectangular columns. 112 pp.
BS EN 1992-1-1:2004 Eurocode 2. Design of concrete structures. General rules and
rules for buildings
Aı tcin, P.-C., High-Performance Concrete, Modern Concrete Technology 5, E & FN
Spon, London, 1998
ASCE, High-Performance Construction Materials and Systems, Technical Report 935011, American Society of Civil Engineers, New York, April 1993.
Farny, James A., and Panarese, William C., High-Strength Concrete,EB114, Portland
Cement Association, 1994
Perry, V., “Industrialization of Ultra-High Performance Ductile Concrete,” Symposium
on High-Strength/High-Performance Concrete, University of
Calgary, Alberta, November 1998.