PCI 3 (Chapter 2) Essentials of Quality
Concrete
Which Major Cement Compounds Correlates with High Early Strength? - ANSC3S particularly
with High Amounts of C3A
C3S Reduction of 5% generally means what? - ANSReduction in Early Strength unless Cement
is Ground Finer.
Which Potential Compound Contributes little to strength gain or heat of hydration? - ANSC4AF
What is the Main Function of C4AF? - ANSIt's Main Function is to use up excess Alumina (A) to
Reduce the Amount of C3A in the Cement.
Which Major Cement Compounds is related to Susceptibility of Cement to Sulfate Attack? -
ANSC3A
What Potential Compound contributes to later Strength Gain, and Produces Less Heat of
Hydration? - ANSC2S
Large Amounts of what Compound Increases Early Strength but will cause Late Strength to be
Lower than normal? - ANSC3A
What Basic types of Information is on a Cement Mill Certificate? - ANS1. Chemical Analyses
2. Calculated Compound Quantities
3. Certain physical tests
Requirements for Types 1,2,3,4,5 cement is given in which ASTM? - ANSASTM 150
Value of Air Content can be found in which ASTM? - ANSASTM 185
For Air Entraining Cement the Value must be between? - ANS16-22%
For Type 3 Cement 1 and 3-day mortar Strengths must be between what PSI? - ANS1800 and
3500 PSI
What does a Loss on Ignition Test assume? - ANSThe amount of moisture and Carbon dioxide
in the cement.
, What do High Values of LOSS on Ignition generally mean? - ANSCement has been in a moist
environment and has partly hydrated.
What is White Cement Primarily used for? - ANSArchitectural Concrete
Typically, White Cement Compounds have High C2S Amounts. What Effects will this have on
Strength Gain Properties? - ANSSlow Strength Gains unless Cement has High Fineness.
Explain the Term Vicat and Gillmore. - ANSSetting Time of Cement Paste as Measured by the
Vicat or Gillmore Apparatus.
According to ASTM C150 what is the Minimum Required Time of Initial Setting of Cement
Paste? - ANS45 minutes Vicat and 60 for Gillmore
Explain the Term Blaine Air Permeability Test and Wagner Turbidimeter Test. - ANSFor
Measuring the Fineness of Cement by Measuring the Sum of Surface Areas of all Particles in a
Sample.
What is the Minimum Fineness for Type 3 cement? - ANSThere is no Minimum for Type 3.
What does it mean if the Blaine Value is Higher? - ANSThe Faster the Cement will Hydrate.
What can be done to Type 3 Cement to Enhance Early Strength Gain? - ANSGrind the Particles
finer.
White Cement is Ground Finer for what reason? - ANSEnhance Early Strength Gain.
Explain the Term False Set - ANSOccurs if Hemi-Hydrate is Present in the Cement. When
Mixed with Water Hemi-Hydrate becomes Gypsum if this occurs after Mixing (False Set) may
occur and concrete cannot be remixed and would need to be discarded.
A Variation in Fine Aggregate Gradation which Results in a Change in Fineness Modulus of ??
from the Developing Mix should be Adjusted. - ANS0.20
What should be done if the Fineness Modulus Decreases? - ANSThe Amount of Fine Aggregate
per Cubic Yard should be Reduced and Amount of Coarse Aggregate Increased.
What might Aggregate Quanity Changes Affect? - ANSThe Color of Concrete.
What should be done if Gradations Vary Widely? - ANSGradation Test should be made more
Frequently.
When does a Chemical Reaction Occur between Alkalines in Cement and Reactive
Aggregates? - ANSWhen Concrete is exposed to Moisture.
Concrete
Which Major Cement Compounds Correlates with High Early Strength? - ANSC3S particularly
with High Amounts of C3A
C3S Reduction of 5% generally means what? - ANSReduction in Early Strength unless Cement
is Ground Finer.
Which Potential Compound Contributes little to strength gain or heat of hydration? - ANSC4AF
What is the Main Function of C4AF? - ANSIt's Main Function is to use up excess Alumina (A) to
Reduce the Amount of C3A in the Cement.
Which Major Cement Compounds is related to Susceptibility of Cement to Sulfate Attack? -
ANSC3A
What Potential Compound contributes to later Strength Gain, and Produces Less Heat of
Hydration? - ANSC2S
Large Amounts of what Compound Increases Early Strength but will cause Late Strength to be
Lower than normal? - ANSC3A
What Basic types of Information is on a Cement Mill Certificate? - ANS1. Chemical Analyses
2. Calculated Compound Quantities
3. Certain physical tests
Requirements for Types 1,2,3,4,5 cement is given in which ASTM? - ANSASTM 150
Value of Air Content can be found in which ASTM? - ANSASTM 185
For Air Entraining Cement the Value must be between? - ANS16-22%
For Type 3 Cement 1 and 3-day mortar Strengths must be between what PSI? - ANS1800 and
3500 PSI
What does a Loss on Ignition Test assume? - ANSThe amount of moisture and Carbon dioxide
in the cement.
, What do High Values of LOSS on Ignition generally mean? - ANSCement has been in a moist
environment and has partly hydrated.
What is White Cement Primarily used for? - ANSArchitectural Concrete
Typically, White Cement Compounds have High C2S Amounts. What Effects will this have on
Strength Gain Properties? - ANSSlow Strength Gains unless Cement has High Fineness.
Explain the Term Vicat and Gillmore. - ANSSetting Time of Cement Paste as Measured by the
Vicat or Gillmore Apparatus.
According to ASTM C150 what is the Minimum Required Time of Initial Setting of Cement
Paste? - ANS45 minutes Vicat and 60 for Gillmore
Explain the Term Blaine Air Permeability Test and Wagner Turbidimeter Test. - ANSFor
Measuring the Fineness of Cement by Measuring the Sum of Surface Areas of all Particles in a
Sample.
What is the Minimum Fineness for Type 3 cement? - ANSThere is no Minimum for Type 3.
What does it mean if the Blaine Value is Higher? - ANSThe Faster the Cement will Hydrate.
What can be done to Type 3 Cement to Enhance Early Strength Gain? - ANSGrind the Particles
finer.
White Cement is Ground Finer for what reason? - ANSEnhance Early Strength Gain.
Explain the Term False Set - ANSOccurs if Hemi-Hydrate is Present in the Cement. When
Mixed with Water Hemi-Hydrate becomes Gypsum if this occurs after Mixing (False Set) may
occur and concrete cannot be remixed and would need to be discarded.
A Variation in Fine Aggregate Gradation which Results in a Change in Fineness Modulus of ??
from the Developing Mix should be Adjusted. - ANS0.20
What should be done if the Fineness Modulus Decreases? - ANSThe Amount of Fine Aggregate
per Cubic Yard should be Reduced and Amount of Coarse Aggregate Increased.
What might Aggregate Quanity Changes Affect? - ANSThe Color of Concrete.
What should be done if Gradations Vary Widely? - ANSGradation Test should be made more
Frequently.
When does a Chemical Reaction Occur between Alkalines in Cement and Reactive
Aggregates? - ANSWhen Concrete is exposed to Moisture.
