Project on Concrete Mix Design for various grades of Concrete
TEST ON MODULE-5
1) AIM: TO DETERMINE THE CONCRETE MIX DESIGN FOR M35 GRADE OF CONCRETE WITH FLY ASH
INTRODUCTION:
- CONCRETE MIX DESIGN GIVES THE ACCURATE MIX DESIGN OF THE CONCRETE.
- BY MIXING OF INGRIDENTS OF CEMENT, SAND AND WATER OR ADMIXTURES TO AQUIRE REQUIRE STRENGTH
- TO AQUIRE REQUIRED PROPERTIES LIKE WORKABILILTY AND DURABILITY OF CONCRETE
GRADE OF CONCRETE: M35
ADMIXTURE: FLY ASH
SIZE OF AGGREGATE: 20
MINIMUM CEMENT CONTENT: 320 KG/M^3 ( IS 456-2000)
EXPOUSRE CONDITION: SEVERE
MAX WATER CEMENT CONTENT: 0.45
CHEMICAL ADMIXTURE: SUPER PLASTICIZER
PROCEDURE:
· TARGET MEAN STRENGTH
F”CK= FCK+1.65*S
WHERE FCK = GRADE OF CONCRETE 35
S= STANDARD DEVIATION = 5 (SEVERE IS 10262-2009)
F”CK = 35+1.65 * 5
= 43.25 N/MM^2
· SELECTION OF WATER CEMENT RATIO
THE MAX WATER CEMENT RATIO IS = 0.45 AS PER IS 456-2000
SO WE CAN ASSUME AS 0.43
· SELECTION OF WATER CONTENT
FROM IS 10262-2009 THE MAX WATER IS 186 LIT( FOR 25 TO 50MM SLUMP)
- FOR INCREASING OF 3% OF WATER CONTENT FOR EVERY EXTRA 25MM TO 50MM SLUMP. SO 6% OF WATER CONTENT INCRASES
- = 186+(6/100)*186
- = 197 LIT ( FOR 100MM SLUMP AS PER PUMPABLE CONCRETE)
- IF ADMIXTURE SUPER PLASTICIZER IS USED SO WATER CONTENT IS REDUCED TO 2%)
- =197*0.8
- = 158 LIT ( WATER REQUIRED)
· CALIUCATION OF CEMENT AND FLY ASH REQUIRED
- W/C RATIO = 0.43
- W/C= 0.43
- C= 158/0.43
- =368 KG/M^3
- FROM IS 456 -2000 MIM CEMENT CEMENT CONETENT IS 320 KG .
- HENCE THE CEMENT CONTENT IS 368 IS DESIRABLE
- FLY ASH CONTENT IS TAKEN AS 30% TO TOTAL CEMENTITIOUS CONTENT
- = 368*0.3
- =110.4
- SO CEMENT REQUIRED = 368-110
- =258 KG/M^3
· VOLUME OF COARSE AGGREGATE AND FINE AGGREGATE CONTENT
- FROM TABLE 3 IS 10262-2009THEVOL OF COARSE AGGREGATE OF 20MM IS 0.62 AS CEMENT WATER RATIO IS 0.50
- IN PRESENT W/C RATIO IS 0.43
- CORRECTED PROPORTION OF VOLUME OF COARSE AGGREGATE IS 0.629
- FOR PUMPABLE CONCRETE IT IS REDUCED BY 10%
- = 0.629*0.90
- = 0.5661(VOL OF C.A)
- SO VOL OF FINE AGGREGATE = 1-0.5661
- =0.4339( VOL OF F.A)
· MIX CALCULATIONS:
- VOL OF CONCRETE = 1 M^3
- VOLOF CEMENT = MASS OF CEMENT/ SP. GRAVITY OF CEMENT *1/1000
- =258/3.15*1/1000
- =0.081 M^3
- C) VOL OF FLY ASH= MASS OF FLYASH/SP. GRAVITY OF FLY ASH*1/1000
= 110/2.2*1/1000
=0.055
- D) VOL OF WATER = MASS OF WATER / SP . GRAVITY OF WATER*1/1000
=158/1*1/1000
=0.158
- E) VOL OF CHEMICAL ADMIXTURE = 7/1.15*1/1000
= 0.006M^3
- F) VOL OF ALL AGGREGATE = A-(B+C+D+E)
= 1-(0.081+0.055+0.158+0.006)
= 1-0.3
= 0.7
- G) VOL OF COARSE AGGREGATE = F * VOL OF COARSE AGGTRGATE * SPECIFIC GRAVITY OF C.A * 1000
= 0.7* 0.566*2.74*1000
= 1066.4 KG/M^3
- F) VOL OF FINE AGGREGATE = F * VOL OF FINE AGGTRGATE * SPECIFIC GRAVITY OF F.A * 1000
= 0.7*0.433*2.74*1000
=830 KG/M^3
· MIX CALCULATIONS
- CEMENT : 258 M^3
- FINE AGGREGATE :830 KG/M^3
- COARSE AGGREGATE : 4KG/M^3
- ADMIXTURE:7 LITRES/M^3
- FLY ASH : 110 KG/M^3
· SO THE MIX PROPORTION IS
- CEMENT:FINE AGGREGATE : COARSE AGGREGATE
- 1:2.25:2.89
- SO FINALLY BY CHANGING THE WATER CEMENT RATIO CAN BE CHANGED AND TRIAL AND ERROR METHODS SHOULD BE DONE.
2) AIM: TO DETERMINE THE CONCRETE MIX DESIGN FOR M50 GRADE OF CONCRETE
INTRODUCTION:
- CONCRETE MIX DESIGN GIVES THE ACCURATE MIX DESIGN OF THE CONCRETE.
- BY MIXING OF INGRIDENTS OF CEMENT, SAND AND WATER OR ADMIXTURES TO AQUIRE REQUIRE STRENGTH
- TO AQUIRE REQUIRED PROPERTIES LIKE WORKABILILTY AND DURABILITY OF CONCRETE
GRADE OF CONCRETE : M50
SIZE OF AGGREGATE: 20
MINIMUM CEMENT CONTENT: 320 KG/M^3 ( IS 456-2000)
EXPOUSRE CONDITION: SEVERE
MAX WATER CEMENT CONTENT: 0.45
CHEMICAL ADMIXTURE: SUPER PLASTICIZER
PROCEDURE:
· TARGET MEAN STRENGTH
F”CK= FCK+1.65*S
WHERE FCK = GRADE OF CONCRETE 35
S= STANDARD DEVIATION = 5 ( SEVERE IS 10262-2009)
F”CK = 50+1.65 * 5
= 58.25 N/MM^2
· SELECTION OF WATER CEMENT RATIO
THE MAX WATER CEMENT RATIO IS = 0.45 AS PER IS 456-2000
SO WE CAN ASSUME AS 0.43
· SELECTION OF WATER CONTENT
FROM IS 10262-2009 THE MAX WATER IS 186 LIT( FOR 25 TO 50MM SLUMP)
- FOR INCREASING OF 3% OF WATER CONTENT FOR EVERY EXTRA 25MM TO 50MM SLUMP. SO 6% OF WATER CONTENT INCRASES
- = 186+(6/100)*186
- = 197 LIT ( FOR 100MM SLUMP AS PER PUMPABLE CONCRETE)
- IF ADMIXTURE SUPER PLASTICIZER IS USED SO WATER CONTENT IS REDUCED TO 2%)
- =197*0.8
- = 158 LIT ( WATER REQUIRED)
· CALIUCATION OF CEMENT REQUIRED
- W/C RATIO = 0.43
- W/C= 0.43
- C= 158/0.43
- =368 KG/M^3
- FROM IS 456 -2000 MIM CEMENT CEMENT CONETENT IS 320 KG .
- HENCE THE CEMENT CONTENT IS 368 IS DESIRABLE
· VOLUME OF COARSE AGGREGATE AND FINE AGGREGATE CONTENT
- FROM TABLE 3 IS 10262-2009THEVOL OF COARSE AGGREGATE OF 20MM IS 0.62 AS CEMENT WATER RATIO IS 0.50
- IN PRESENT W/C RATIO IS 0.43
- CORRECTED PROPORTION OF VOLUME OF COARSE AGGREGATE IS 0.629
- FOR PUMPABLE CONCRETE IT IS REDUCED BY 10%
- = 0.629*0.90
- = 0.5661(VOL OF C.A)
- SO VOL OF FINE AGGREGATE = 1-0.5661
- =0.4339( VOL OF F.A)
· MIX CALCULATIONS:
- VOL OF CONCRETE = 1 M^3
- VOLOF CEMENT = MASS OF CEMENT/ SP. GRAVITY OF CEMENT *1/1000
- =368/3.15*1/1000
- =0.116 M^3
- C) VOL OF WATER = MASS OF WATER / SP . GRAVITY OF WATER*1/1000
=158/1*1/1000
=0.158
D) VOL OF CHEMICAL ADMIXTURE = 7/1.15*1/1000
= 0.006M^3
E) VOL OF ALL AGGREGATE = A-(B+C+D)
= 1-(0.116+0.158+0.006)
= 1-0.28
= 0.72
F) VOL OF COARSE AGGREGATE = E * VOL OF COARSE AGGTRGATE * SPECIFIC GRAVITY OF C.A * 1000
= 0.72* 0.566*2.74*1000
= 1116.6KG/M^3
G) VOL OF FINE AGGREGATE = F * VOL OF FINE AGGTRGATE * SPECIFIC GRAVITY OF F.A * 1000
= 0.72*0.433*2.74*1000
=854.2 KG/M^3
· MIX CALCULATIONS
- CEMENT : 368 M^3
- FINE AGGREGATE :2 KG/M^3
- COARSE AGGREGATE : 6KG/M^3
- ADMIXTURE:7 LITRES/M^3
· SO THE MIX PROPORTION IS
- CEMENT:FINE AGGREGATE : COARSE AGGREGATE
- 1:2.3:3.03
- SO FINALLY BY CHANGING THE WATER CEMENT RATIO CAN BE CHANGED AND TRIAL AND ERROR METHODS SHOULD BE DONE