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8/14/2019 Tests on Portland Cement.pdf
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Dr. Kimberly KurtisSchool of Civil Engineering
Georgia Institute of TechnologyAtlanta, Georgia
Tests on Portland Cement
Composition
~ 5CSH2CaSO42H2OCalcium sulfate dihydrate
5 - 15C4AF4CaOAl2O3Fe2O3Tetracalcium aluminoferrite
5 - 10C3A3CaOAl2O3Tricalcium aluminate
15 - 30C2S2CaO SiO2Dicalcium silicate
50 - 70C3S3CaOSiO2Tricalcium silicate
Mass
(%)
Shorthand
NotationChemical FormulaChemical Name
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CompositionThe relative quantities of each of these phases affects:
setting time
rate of strength development
overall strength
durability
color
It is important, then, to know the composition of the
cement.
Physical Properties
Fineness
Soundness
Consistency
Setting time
False set and flash set
Compressive strength
Heat of hydration
Loss on ignition
Density
Bulk density
Sulfate expansion
Tests on Portland, Blended & Hydraulic CementsTests on Portland, Blended & Hydraulic Cements
Chemical Properties
Chemical analysis
Compound composition
Chemical limits
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Alite, C3S
Belite, C2S
Width o f field = 0.31 mm
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http://www.bruker-axs.de/
Chemical AnalysisChemical Analys is
ASTM C 114 Standard Test
Methods for Chemical Analysis
of Hydraulic Cement
Manganic oxideMn2O3
Sulfide sulfur
Titanium dioxideTiO2
Phosphorus pentoxideP2O5
Zinc oxideZnO
Potassium oxideK2O
Sodium oxideNa2O
Loss on ignitionLOI
Sulfur trioxideSO3
Magnesium oxideMgO
Calcium oxideCaO
Ferric oxideFe2O3
Aluminum oxideAl2O3
Silicon dioxideSiO2
Major components
Minor components
Separate determinations
Insoluble residue
Free calcium oxide
CO2 (carbon dioxide)
Water-soluble alkali
Chloroform soluble organic
substances
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ASTM C114
Oxide %
SiO2 20.6
Al2O3 5.07
Fe2O3 2.90
CaO 63.9
MgO 1.53
K2O 0.73
Na2O 0.15SO3 2.53
LOI 1.58
Oxide Analysis
+ other trace elements
Oxide Shorthand Common Name
CaO C lime
SiO2 S silica
Al2O3 A alumina
Fe2O3 F ferric oxide
MgO M magnesia
H2O H water
K2O Kalkalis
Na2
O N
SO3 sulfateS
CO2 carbonateC
90 95%
(Only valid when A/F 0.64)
C2S = 2.87S 0.75C3S
C3A = 2.65A 1.69F
C4AF = 3.04F
Bogue Composition
Compound CompositionCompound Composition
C3S = 4.07C 7.60S 6.72A 1.43F 2.85S
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Bogue Composition: ExampleOxide Analysis
C3S = 4.07(63.9) 7.60(20.6) 6.72(5.07)
1.43(2.90) - 2.85(2.53) = 58.1
C2S = 2.87(20.6) 0.754(58.1) = 15.6
C3A = 2.65(5.07) 1.69(F 2.90) = 8.5
C4AF = 3.04(2.90) = 8.8
Calculated Phase Composition
Oxide %
SiO2 20.6
Al2O3 5.07
Fe2O3 2.90
CaO 63.9
MgO 1.53
K2O 0.73
Na2O 0.15
SO3 2.53
LOI 1.58
9%C4AF
9%C3A
16%C2S
58%C3SBogue Potential Composition:
Oxide %
SiO2 20.6
Al2O3 5.07
Fe2O3 2.90
CaO 63.9
MgO 1.53
K2O 0.73
Na2O 0.15
SO3 2.53
LOI 1.58
Typical Chemical Composition of Portland Cement
Oxide Analysis
+ other trace elements
Sodium equivalent, Na2Oe
Na2Oe = Na2O + (0.658 x K2O)
Na2Oe = 0.15 + (0.658 x 0.73)
Na2Oe = 0.63%
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Bogue CompositionThe Bogue equations are based on the following assumptions:
1) All 4 phases are pure2) All the F present occurs as C4AF, and the quantities of A =
0.64(%F) and C = 1.40 (%F) are subtracted from the
appropriate totals.
3) The remaining Al2O3 is combined as C3A and a further quantity
of C = 1.65 (% Al2O3) is subtracted fromt eh total remaining
CaO.
4) The SiO2 combines initially with CaO to form C2S giving a
provisional C2S figure. The CaO combining with SiO2 =
2.87%(SiO2) is subtracted from the total CaO figure, and the
remaining CaO is then combined with a part of the C2S =
4.07(%CaO) to form C3S.As a resul t, Bogue composi tions may be of f by as much as
10% compared to XRD-determined compositions.
BogueXRD
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Chemical LimitsChemical Limits
6.06.06.06.06.0MgO, max. %
3.02.53.03.03.0LOI, max. %
0.750.750.750.750.75Insoluble residue,
max. %
Cement Type
3.0
n/a
2.3
n/a
3.5
4.5
3.0
n/a
3.0
3.5
SO3, max. %
C3A 8%
C3A > 8%
-6.5-6.0-Fe2O3, max. %
---6.0-Al2O3, max. %
---20.0-SiO2, min. %
VIVIIIIII
ASTM C 150 Portland Cement - Chemical Requirements
Chemical LimitsChemical Limits
Cement Type
25----C4AF + 2 C3A,
max. %
57158-C3A, max. %
-25---C2S, min. %
-35---C3S, max. %
VIVIIIIII
ASTM C 150 Portland Cement - Chemical Requirements
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Chemical LimitsChemical Limits
Cement Type
0.600.600.600.600.60Na2Oe, max. %
---58-C33 + C3A, max. %
--5--C3A, max. %
--8--C3A, max. %
VIVIIIIII
ASTM C 150 Portland Cement Optional Chemical Requirements
Chemical LimitsChemical Limits
5.04.03.0LOI, max. %
-0.03*-Water-soluble alkali, max. %
6.0--MgO, max. %
-2.02.0Sulfide sulfur (S), max. %
-1.01.0Insoluble residue, max. %
Cement Type
4.04.03.0Sulfur reported as SO3, max.
%
I(PM),
I(PM)-A, P,
PA,
IP, IP-A
S, SAI(SM), I(SM)-
A, IS, IS-A
ASTM C 595 Blended Cement - Chemical Requirements
*Only required when cement is specified to be nonstaining to limestone
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FinenessFineness
Fineness of cement is also important; it affects:
rate of hydration
rate of setting
rate of hardening
durability (ASR)
rate of carbonation during storage
cost
rate of gypsum addition
bleeding
However, later strength is not directly affected.
Neville, Fig. 1.5
FinenessFineness
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Approx. 95% 45 microns
Average diameter ~ 15
microns
Those retained on the No 200
sieve (75 microns) will never
hydrate completely
Those retained on the No 325
sieve (45 microns) will be
difficult to hydrate completely
FinenessFineness
Type III >> Type I, II, V > Type IV
Fineness is generally described as the specific surface of the
cement, which is the surface area expressed in m2/kg
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Lea and Nurse Air PermeabilityLea and Nurse Air Permeability
Relates flow of fluid (air)through a bed of granular
material (cement) to the specific
surface area of that granular
material
By knowing cement, a bed 10mmthick with porosity of 4.75% is
made; air is passed through at
constant velocity; pressure drop
is measured.
Sw= 14 [(3Ah1)/(KLh2)]
0.5
(1-)
Blaine Air PermeabilityBlaine Air Permeabili ty
Blaine Air Permeability
(ASTM C 204)
With the Lea Nurse method, air
passes through the bed at a constant
rate
In the Blaine test, a known volume of
air passes at a constant pressure
through the bed
The rate of flow decreases steadily
The time for flow to occur is
measured for a given apparatus and a
standard porosity of 5% (0.500).
Sw = K2t0.5
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WagnerWagner TurbidimeterTurbidimeter
Wagner Turbidimeter
(ASTM C 115)
Uses a photoelectric cell to
measure light passing through
cement particles suspended
in kerosene
Test is based on Stokes Law
that states that a sphere will
obtain a constant velocity
under the action of gravity
Allows calculation of particle-
size distribution (psd)
Blaine, in general, is 1.8X Wagner
Laser Particle Size AnalyzerLaser Particle Size Analyzer
Laser particle sizeanalyzer
Particle-size distribution
(psd)
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Cement FinenessCement Fineness
ASTM C 430
Sample washed over 45-m (# 325) sieve Used in production
Limits for pozzolans and slag (ASTM C 595)
Cement FinenessCement Fineness
Requirements for Type I, II, IV & V
(No requirements for Type III)
Minimum, m2/kg
Air Permeability Turbidimeter
ASTM C 150 &
AASHTO M 85280 160
Maximum, m2/kgAASHTO M 85 400 220
No limits for blended cement (ASTM C 595) or hydraulic cements
(ASTM C 1157) but values must be reported on mill test reports
Typical values, m2/kg 350-380 Type I
450-600 Type III
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SoundnessSoundness
Soundness - ability of hardened paste to
maintain volume after setting
Unsoundness (abnormal expansion)
caused by hard-burned CaO or MgO
22 )(OHCaOHCaO +
22 )(OHMgOHMgO +
ASTM C 151 Standard Test Method for
Autoclave Expansion of Portland Cement
Expansion for all portland,
blended & hydraulic cements 0.80%
ConsistencyConsistency
Consistency of Cement Paste
Penetration of 10 1 mm of Vicat plunger
ASTM C 187 Standard Test Method for
Normal Consistency of Hydraulic Cement
Consistency of Mortar
Flow table
ASTM C 1437 Standard Test Method for
Flow of Hydraulic Mortar
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Setting TimeSetting Time
Initial Set
Final Set
Time from moment water is added until the paste
ceases to be fluid and plastic
Time from moment water is added for the paste to
acquire a certain degree of hardness
Setting Time: Standard TestSetting Time: Standard Test
Vicat Needle
ASTM C 191 Standard Test Method for
Time of Setting of Hydraulic Cement by
Vicat Needle
Initial set occurs when needle penetrates
- after 30s - 25 mm (1 inch) into paste
Final set occurs when there is no visible
penetration
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Setting Time: Field MeasurementsSetting Time: Field Measurements
Concrete penetrometer, measures
resistance to penetration in sieved mortar
samples
Pocket penetrometers
Setting Time: Standard TestSetting Time: Standard Test
Gillmore Needles
ASTM C 266 Standard Test
Method for Time of Setting of
Hydraulic-Cement Paste by
Gillmore Needles
Setting determined as time when
paste resists indentation by
needles
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Setting TimeSetting Time
ASTM C 150 Por tland Cement
Initial Set, not less than (h:min)
Final Set, not more than (h:min)
Vicat Needle Gillmore Needles
0:45
6:15
1:00
10:00
ASTM C 595 Blended Cement
Initial Set, not less than (h:min)
Final Set, not more than (h:min)
0:45
7:00
ASTM C 1157 Hydrau lic Cement
Initial Set, not less than (h:min)
Final Set, not more than (h:min)
0:45
7:00
Setting TimeSetting Time
0 100 200 300 400
Type V
Type IV
Type III
Type II
Type I
Time of Set (Minutes) - Vicat Method
Initial
Final
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False Set and Flash SetFalse Set and Flash Set
False Set Loss of plasticity shortly after mixing little heat
Due to hemihydrate (plaster) in cement
hydrating to gypsum
Workability restored by additional mixing
Early Stiffening Early Stiffening
False Set and Flash SetFalse Set and Flash Set
False Set Loss of plasticity shortly after mixing little heat
Due to hemihydrate (Plaster) in cement
hydrating to Gypsum
Workability restored by additional mixing
Flash Set Rapid & early loss of workability significant heat
Due to rapid reaction of aluminates when
insufficient sulfate present
Workability cannot be restored
Early Stiffening Early Stiffening
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Compressive StrengthCompressive Strength
ASTM C 109 Standard Test Method
for Compressive Strength of Hydraulic
Cement Mortars.
50-mm (2-inch) mortar cubes
Sand:Cement = 2.75:1
Water/Cement = 0.485 for portland
cement (0.460 for air-entraining
portland cement)
Sufficient water for flow 110 5 for
blended (ASTM C 595) and
hydraulic (ASTM C 1157) cements
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ASTM C 150 Standard Specification for Portland Cement
Cement Type
21.0
(3050)
17.0
(2470)
---28 days
15.0
(2180)
7.0
(1020)
-17.0
(2470)
19.0
(2760)
7 days
8.0
(1160)
-24.0
(3480)
10.0
(1450)
12.0
(1740)
3 days
--12.0
(1740)
--1 day
VIVIIIIII
Age
Minimum Strength Requirements, MPa (psi)
Compressive StrengthCompressive Strength
Lower strengths permitted for air-entraining cements (Types IA, IIA & IIIA)
and when heat of hydration option is specified for Type II cement
ASTM C 595 Standard Specification for Blended Hydraulic Cements
Cement Type
21.0
(3140)
11.0
(1600)
25.0
(3620)
25.0
(362)
28 days
11.0
(1600)
5.0
(720)
18.0
(2610)
20.0
(2900)
7 days
--11.0
(1600)
13.0
(1890)
3 days
PSIS(MS),
IP(MS)
I(SM), IS,
I(PM), IP
Age
Minimum Strength Requirements, MPa (psi)
Compressive StrengthCompressive Strength
Lower strengths permitted for air-entraining cements (with suffix A)
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ASTM C 1157 Standard Specification for Hydraulic Cement
Cement Type
17-17---28 days
5101017-177 days
-551017103 days
----10-1 day
LHMHHSMSHEGU
Age
Minimum Strength Requirements (MPa)
Compressive StrengthCompressive Strength
ASTM C 1157 Standard Specification for Hydraulic Cement
-60
(8700)
40
(5800)
30
(4350)
20
(2900)
15
(2175)
Maximum Strength,
MPa (psi)
45
(6525)
35
(5075)
25
(3625)
17
(2465)
10
(1450)
5
(725)
Minimum Strength,
MPa (psi)
45352517105Strength Range
Minimum Strength Requirements (MPa)
Compressive StrengthCompressive Strength
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Heat of HydrationHeat of Hydration
Heat evolution in portland cement tested by conduction calorimetry
Heat of Solution Test
ASTM C 186 Standard Test Method for
Heat of Hydration of Portland Cement
Conduction Calorimetry
Heat of HydrationHeat of Hydration
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Heat of HydrationHeat of Hydration
Moderate Heat
of Hydration
Low Heat of
Hydration
ASTM C 150
Portland Cement
Type II (Option)
290 kJ/kg at 7 days
Type IV
250 kJ/kg at 7 days
290 kJ/kg at 28 days
Heat of HydrationHeat of Hydration
Moderate Heat
of Hydration
Low Heat of
Hydration
ASTM C 150
Portland Cement
Type II (Option)
290 kJ/kg at 7 days
Type IV
250 kJ/kg at 7 days
290 kJ/kg at 28 days
ASTM C 595
Blended Cement
Suffix -MH Suffix -LH
250 kJ/kg at 7 days
290 kJ/kg at 28 days
290 kJ/kg at 7 days
330 kJ/kg at 28 days
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Heat of HydrationHeat of Hydration
Moderate Heat
of Hydration
Low Heat of
Hydration
ASTM C 150
Portland Cement
Type II (Option)
290 kJ/kg at 7 days
Type IV
250 kJ/kg at 7 days
290 kJ/kg at 28 days
ASTM C 595
Blended Cement
Suffix -MH Suffix -LH
250 kJ/kg at 7 days
290 kJ/kg at 28 days
290 kJ/kg at 7 days
330 kJ/kg at 28 days
ASTM C 1157
Hydraulic Cement
Type MH Type LH
250 kJ/kg at 7 days
290 kJ/kg at 28 days
290 kJ/kg at 7 days
Loss on IgnitionLoss on Ignition
ASTM C 114 Standard Test Methods
for Chemical Analysis of Hydraulic
Cement
Loss on ignition LOI
Sample ignited at 900 to 1000C
(1650 to 1830F)
High LOI indicates prehydration
and/or carbonation
Improper or prolonged storage
(transportation)
ASTM C 150 Portland Cement LOI 3.0% (2.5% for Type IV)
ASTM C 595 Blended Cement LOI 3.0 5.0%
ASTM C 1157 Hydraulic Cement No limit must be reported
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DensityDensity
Le Chatelier flask - ASTM C 188 Standard
Test Method for Density of Hydraulic Cement
HeliumHelium pycnometerpycnometer
Range= 3100 to 3250 kg/m3
Average = 3150 kg/m3 (196 lb/ft3)
Not indicator of quality
Used for mixture proportioning
calculations
Relative density (specific gravity) = 3.15
Bulk DensityBulk Density
Bulk density of cement varies
between
830 kg/m3 (52 lb/ft3)
and
1650 kg/m3 (103 lb/ft3).
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ASTM C 452 Standard Test Method for Potential Expansion ofPortland-Cement Mortars Exposed to Sulfate
Sulfate ExpansionSulfate Expansion
Gypsum added to cement to yield 7.0% SO3 (by mass of
cement + gypsum)
Mortar bars stored in water
Length change monitored periodically
Only applicable to portland cements
ASTM C 150 Portland Cement
Optional requirement for
Type V Sulfate-Resisting
Portland Cement
Expansion 0.040%
at 14 days
Limits for C3A, C4AF
+ 2C3A, SiO2 & Fe2O3not required