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1.CEMENT CONCRETE MIX DESIGN
Concrete has four component system, that is, cement, water, coarse aggregate and fine aggregate
Judicious combination of - fly ash, ground granulated blast furnace slag, silica fume, rice husk ash, metakaoline, superplasticizer, Plasticizers AEA, Retarder and fibres
Need has been further augmented to proportion concrete mixes in different specification including IS:456-2000.
PROPORTIONING OF MATERIALS TO BE USED TO OBTAIN CONC. OF REQD.
STRENGTH,
DURABILITY
WORKABILITY
Concrete has four component system, that is, cement, water, coarse aggregate and fine aggregate
Judicious combination of - fly ash, ground granulated blast furnace slag, silica fume, rice husk ash, metakaoline, superplasticizer, Plasticizers AEA, Retarder and fibres
Need has been further augmented to proportion concrete mixes in different specification including IS:456-2000.
PROPORTIONING OF MATERIALS TO BE USED TO OBTAIN CONC. OF REQD.
STRENGTH,
DURABILITY
WORKABILITY
2.GENERAL- Concrete Mix
Satisfactory quality both in its fresh and hardened
states
Trial mixes using certain established relationships
Basic principles Abram’s law for strength
Proportioning of concrete mixes can be regarded as procedure set to proportion the economical concrete mix for specified durability and grade for required site conditions.
Satisfactory quality both in its fresh and hardened
states
Trial mixes using certain established relationships
Basic principles Abram’s law for strength
Proportioning of concrete mixes can be regarded as procedure set to proportion the economical concrete mix for specified durability and grade for required site conditions.
3.Following major modifications
Adoption of any other methods of proportioning
Applicability of the guidelines has been specified for M25 above M50 (IRC SP-76-2008)
Selection of W/C ratio, water content & estimation of coarse/ fine aggregate content have been modified
Illustrative examples using fly ash and silica fume
ACI 211.1 (Re-approved 1997) ‘Standard practice for selecting proportions for normal, heavyweight, and mass concrete’,
IS:10262 First Revision (Draft).
Adoption of any other methods of proportioning
Applicability of the guidelines has been specified for M25 above M50 (IRC SP-76-2008)
Selection of W/C ratio, water content & estimation of coarse/ fine aggregate content have been modified
Illustrative examples using fly ash and silica fume
ACI 211.1 (Re-approved 1997) ‘Standard practice for selecting proportions for normal, heavyweight, and mass concrete’,
IS:10262 First Revision (Draft).
4. SCOPE
Proportioning to achieve specified characteristics at specified age, workability of fresh concrete and durability requirements
Standard is applicable for M25 to M50 grades of concrete normally used for concrete pavements and
Above M50 for special applications like white topping as per IRC SP-76-2007.
Proportioning to achieve specified characteristics at specified age, workability of fresh concrete and durability requirements
Standard is applicable for M25 to M50 grades of concrete normally used for concrete pavements and
Above M50 for special applications like white topping as per IRC SP-76-2007.
5.RELEVANT DEFINITIONS
For the purpose of these guidelines, the definitions given in IS:456-2000,
IS: 4845 and IS: 6461 (Part-I to IV)
The commonly used terms are defined
For the purpose of these guidelines, the definitions given in IS:456-2000,
IS: 4845 and IS: 6461 (Part-I to IV)
The commonly used terms are defined
6.Materials
Ordinary Portland Cement, 33 Grade, IS:269
Ordinary Portland Cement, 43 Grade, IS:8112
Ordinary Portland Cement, 53 Grade, IS:12269
Portland Pozzoloana Cement IS:1489, Part I
Portland Slag Cement, IS:455
Retarders, plasticisers and superplasticisers - IS: 9103
0.5 percent, 1 percent and 2 percent (IS: 456-2000)
Air entraining admixture - freezing weather, 5 + 1.5 %
2 % air - control of bleeding/ segregation
Ordinary Portland Cement, 33 Grade, IS:269
Ordinary Portland Cement, 43 Grade, IS:8112
Ordinary Portland Cement, 53 Grade, IS:12269
Portland Pozzoloana Cement IS:1489, Part I
Portland Slag Cement, IS:455
Retarders, plasticisers and superplasticisers - IS: 9103
0.5 percent, 1 percent and 2 percent (IS: 456-2000)
Air entraining admixture - freezing weather, 5 + 1.5 %
2 % air - control of bleeding/ segregation
7.Materials Fibres
IS: 456-2000, for special applications
polypropylene/ polyester/polyethylene/ nylon
Uniformly dispersed
Improve the ductility and fatigue of high performance/ high strength concrete, polymeric fibres (0.2-0.4%)
Water absorption < 0.3%
Reduction in the strength < 5 percent
Entrapped air content < 3 %
Diameter - 10-70 micron and
specific gravity - 0.91- 1.34.
Steel fibres (Structural) shall be as per IRC: SP:46.
IS: 456-2000, for special applications
polypropylene/ polyester/polyethylene/ nylon
Uniformly dispersed
Improve the ductility and fatigue of high performance/ high strength concrete, polymeric fibres (0.2-0.4%)
Water absorption < 0.3%
Reduction in the strength < 5 percent
Entrapped air content < 3 %
Diameter - 10-70 micron and
specific gravity - 0.91- 1.34.
Steel fibres (Structural) shall be as per IRC: SP:46.
8.Aggregate
Coarse Aggregate
Loss Angeles Abrasion < 35%
Alkali aggregate reactivity, IS: 456
Flakiness index of < 40%
Water absorption < 2%,
> 2% may be allowed subject to conformance to soundness test.
Subject to 5 percent.
Rounded and semi crushed aggregates with caution
Fine Aggregate- Same
Coarse Aggregate
Loss Angeles Abrasion < 35%
Alkali aggregate reactivity, IS: 456
Flakiness index of < 40%
Water absorption < 2%,
> 2% may be allowed subject to conformance to soundness test.
Subject to 5 percent.
Rounded and semi crushed aggregates with caution
Fine Aggregate- Same
9.Mineral Admixtures
Flyash (as per IS 3812 (Part-I)-2003 : Max. 20%
ii) Granulated blast furnace slag (as per IS:12089)
Silica fume (as per IS:15388-2003 and IS:456-2000, IRC:SP- 70)
Very fine non-crystalline silicon dioxide
By- product of the manufacture of silicon, ferrosilicon
or the like, from quartz & carbon in electric arc furnace 20000C
Content - 5 to 10 %
Higher grades of concrete i.e. M50 and above
High performance concrete with special requirements
Higher abrasion resistance of concrete
iv) Metakaoline: Maximum : 20%
Flyash (as per IS 3812 (Part-I)-2003 : Max. 20%
ii) Granulated blast furnace slag (as per IS:12089)
Silica fume (as per IS:15388-2003 and IS:456-2000, IRC:SP- 70)
Very fine non-crystalline silicon dioxide
By- product of the manufacture of silicon, ferrosilicon
or the like, from quartz & carbon in electric arc furnace 20000C
Content - 5 to 10 %
Higher grades of concrete i.e. M50 and above
High performance concrete with special requirements
Higher abrasion resistance of concrete
iv) Metakaoline: Maximum : 20%
10.DATA FOR MIX PROPORTIONING
Type of cement
Grade designation (compressive / flexural strength)
Maximum nominal size of aggregate
Minimum and maximum cement contents
Maximum water-cement ratio
Workability
Method of transporting and placement of concrete
Temperature of concrete at the time of placement. 5- 30oC
Type of aggregates
a chemical and mineral admixture
fibres and type and specification
Type of cement
Grade designation (compressive / flexural strength)
Maximum nominal size of aggregate
Minimum and maximum cement contents
Maximum water-cement ratio
Workability
Method of transporting and placement of concrete
Temperature of concrete at the time of placement. 5- 30oC
Type of aggregates
a chemical and mineral admixture
fibres and type and specification
11.DESIGN STRENGTH
12.samples > 30. To validate and improve the job mix formula
13.Selection of Water – Cement Ratio for the Given Grade
14.Selection of Water Content
Angular coarse aggregate & 20 mm + 5 mm slump
Water content -reduced by 10 kg for sub-angular agg.
20 kg for gravel with some crushed particles
25 kg for rounded gravel
Plasticising admixtures decrease water by 5 – 10%
Superplasticising 20 – 30%
Angular coarse aggregate & 20 mm + 5 mm slump
Water content -reduced by 10 kg for sub-angular agg.
20 kg for gravel with some crushed particles
25 kg for rounded gravel
Plasticising admixtures decrease water by 5 – 10%
Superplasticising 20 – 30%
15.Water Content /Cum of Concrete for Nominal Maximum Size
of Aggregate (with out Plasticiser /Superplasticiser)
of Aggregate (with out Plasticiser /Superplasticiser)
16.Calculation of Cementitious Material Content
Minimum cement content shall be 325 kg/m3
Maximum cement content shall be 425 kg/m3
Minimum cement content shall be 325 kg/m3
Maximum cement content shall be 425 kg/m3
17.COARSE AGGREGATES REQUIREMENTS - FOR SINGLE
SIZED AND GRADED AGGREGATES
SIZED AND GRADED AGGREGATES
18.FINE AGGREGATES REQUIREMENTS
19.Coarse Aggregate /unit Volume of Total Aggregate
(for Different Zones of Fine Aggregate as per IS: 383)
(for Different Zones of Fine Aggregate as per IS: 383)
20.Estimation of coarse and fine aggregate contents
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