Frequently Asked Questions

In This Section

Other Sources for Answers

Search other resources on the ACI website for answers to technical questions

Technical Questions

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



Found 49 FAQs.

Question: What is D-cracking?

Question: Acceptable concrete cracking

Question: What is mass concrete?

Question: When should saw cuts be made on a concrete slab?

Question: Maximum temperature limits for hot-weather concreting

Question: Heat of hydration and the importance of controlling it

Question: How can the effectiveness of curing be measured?

Question: Alternative methods for measuring crack width

Question: Can fresh concrete be used around aluminum framing or in aluminum molds??

Question: What are shrinkage-compensating expansive cement and concrete?

Question: What fibers are used in concrete?

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

Question: What steps are taken in the repair of concrete structures?

Question: Do we always need to repair cracked concrete?

Question: How is the shrinkage of concrete determined?

Question: Embedded metals other than reinforcing steel

Question: Why are fibers used in concrete?

Question: Using core strength to calculate compressive strength of an existing structure

Question: Strength of concrete

Question: The effect of joints on the durability of concrete structures

Question: The importance of proper drainage

Question: Reinforced concrete vs. prestressed concrete

Question: Definition of “hot cement”

Question: Pozzolans in mass concrete

Question: The effect of pozzolans on shrinkage

Question: Characteristics of aggregate affecting concrete strength

Question: Specialty admixtures

Question: Protecting against excessive expansion due to alkali-aggregate reaction (AAR)

Question: How should the concrete be consolidated to obtain a complete filling of the forms and around the...

Question: What is curing?

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

Question: Can the heat liberated by the hydrating cement be relied on to give protection during cold weather?

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

Question: What other uses are there for the pulse velocity?

Question: Curling, shrinkage, and w/cm

Question: Increasing the load capacity of a slab-on-ground using an overlay

Question: Difference between a contraction joint, isolation joint, expansion joint, construction joint, an...

Question: Determining the cause of a crack

Question: Temperature limits for mass concrete

Question: Minimum Dimension of a Structure

Question: Water Curing Mass Concrete Structures

Question: Is chiseled concrete a common technique for facades

Question: Why use fiber-reinforced concrete?

Question: How should the appropriate fiber be selected for a specific application, and how is fiber dosage...

Question: What is the minimum fiber dosage? Is it possible to use less than the minimum dosage?

Question: What is minimum reinforcement for crack-width control and how is design accomplished using fiber?

Question: What properties of concrete are enhanced by the addition of fiber?

Question: Are there any challenges or common issues encountered during the testing of fiber-reinforced con...

Question: Does incorporating fiber as an alternative to traditional reinforcement enhance the environmenta...