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Technical Questions

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



Found 40 FAQs.

Question: What is the intention of the ACI 318 Building Code?

Question: Shear Design Provisions in ACI 318-19

Question: Are stiffness modifiers mandatory in the ACI 318 Code?

Question: Legacy building codes

Question: Epoxy-coated reinforcement and cover depth against ground

Question: Load factors used in the 1963 building code

Question: Two-way slabs design, ACI 318 vs. FEM

Question: The intent of the 0.8 factor in Section 17.7.1.2.1 of ACI 318-19

Question: Low-strength cylinder test results

Question: Simplified design for reinforced concrete buildings

Question: Guidance on designing reinforced concrete retaining walls

Question: Definition of shallow and deep foundations

Question: Minimum thickness of bearing walls

Question: Shear reinforcement for beam-column connections

Question: Chloride concentration in soil and exposure classes

Question: Minimum concrete cover for balconies with PT cables

Question: Governing version of ACI 318

Question: ACI code for evaluating existing buildings prior to repair

Question: Curing Cylinders for Acceptance Testing

Question: Size of test cylinder

Question: Slabs-on-ground

Question: Standards for 7-day and 28-day strength test results

Question: How is the required strength selected, measured, and obtained?

Question: What nominal maximum sizes of aggregate are recommended?

Question: Determining the cause of a crack

Question: Using cube tests in lieu of cylinder tests

Question: Precautions against sulfate attack

Question: What is reinforced concrete?

Question: Who selects the requirements for concrete for a project?

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

Question: Knowledge of concrete properties

Question: Requirements for a successful concrete structure

Question: The importance of reinforcement in concrete

Question: Reinforced concrete vs. prestressed concrete

Question: The importance of concrete cover

Question: Epoxy-coated reinforcement

Question: Punching shear check for shear wall foundations

Question: Requirements for durable concrete

Question: Strength of concrete

Question: Reinforcement termination in wastewater concrete containment