Frequently Asked Questions

Technical Questions

ACI Committees, Membership, and Staff have answered common questions on a variety of concrete related topics.




Question: Curing and curling of concrete slabs over vapor retarders

Question: What is curing?

Question: When is steam curing used?

Question: What procedure should be followed for standard curing of specimens for strength tests?

Question: Is there any measure of the completeness or adequacy of curing?

Question: What methods are commonly used to ensure sufficient moisture for curing concrete?

Question: How does the temperature influence curing?

Question: How can the effectiveness of curing be measured?

Question: Can the strength gain of concrete that has ceased due to drying out at early ages be restored by moist curing?

Question: Does additional curing improve the properties of concrete in other ways than in strength?

Question: Are any temperature limitations necessary in curing concrete in hot weather?

Question: What is the importance of curing on strength?

Question: Water Curing Mass Concrete Structures

Question: Addition of lime in curing tanks

Question: Is storing the specimens on the structure always a satisfactory procedure for estimating in-place strength?

Question: What is mass concrete?

Question: Requirements for durable concrete

Question: Heat of hydration and the importance of controlling it

Question: Advantages of low-density aggregate

Question: What is meant by properly cured concrete?

Question: Curing Cylinders for Acceptance Testing

Question: Low-strength cylinder test results

Question: Estimating in-place concrete strength

Question: Aging of concrete

Question: Factors affecting permeability

Question: The effect of pozzolans on shrinkage

Question: Are polymer concrete and polymer-modified concrete used in repairs?

Question: Does the method of molding test specimens affect the test results?

Question: How are properties of concrete in the structure measured?

Question: Popouts or popoffs?

Question: Consolidation of concrete—required or not?

Question: How to Control Mass Concrete Temperature during Construction

Question: Factors governing the strength of concrete

Question: What test conditions affect the results of compressive strength tests of concrete?

Question: Curing Test Specimen at High Temperatures


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