Frequently Asked Questions

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Technical Questions

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Found 55 FAQs.

Question: Embedded metals other than reinforcing steel

Question: Curing and curling of concrete slabs over vapor retarders

Question: What is the difference between synthetic microfibers and macrofibers?

Question: What nominal maximum sizes of aggregate are recommended?

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

Question: Determining the cause of a crack

Question: Acceptable concrete cracking

Question: Mixture design and strength submittals

Question: Curing Cylinders for Acceptance Testing

Question: How does the testing methodology for fiber-reinforced concrete differ from that of traditional c...

Question: Tolerances for floors supporting operable partitions

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

Question: How do fibers affect the workability of concrete? Do fibers require additional water for placement?

Question: Strength of concrete

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

Question: ACI code for evaluating existing buildings prior to repair

Question: How does the type of fiber (material, shape, and form) impact the design methodology used for fi...

Question: Reinforced concrete vs. prestressed concrete

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

Question: Simplified design for reinforced concrete buildings

Question: Reinforcement termination in wastewater concrete containment

Question: How is reinforced concrete designed using fibers instead of traditional steel?

Question: Governing version of ACI 318

Question: Could a sulfate-resisting cement and slag cement be combined and used for concrete exposed to su...

Question: A fiber manufacturer uses a proprietary design method. How can the validity of this method be co...

Question: Slabs-on-ground

Question: Guidance on designing reinforced concrete retaining walls

Question: Knowledge of concrete properties

Question: Tolerances for concrete slabs supporting steel tanks

Question: What is the difference between corrected and uncorrected weight in a concrete mix design?

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

Question: Minimum concrete cover for balconies with PT cables

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

Question: Is chiseled concrete a common technique for facades

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

Question: Why use fiber-reinforced concrete?

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

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

Question: Standard on detailing of concrete reinforcement

Question: Load factors used in the 1963 building code

Question: Substantial structural damage

Question: Design of Slabs-on-ground

Question: If time is not available for preliminary tests, how can the desired strengths be ensured?

Question: Painting the floor

Question: Will fiber-reinforced concrete have a hairy appearance?

Question: Minimum thickness of bearing walls

Question: Design Properties of Lightweight Concrete

Question: Shear Design Provisions in ACI 318-19

Question: What is calcium-aluminate cement?

Question: Chloride concentration in soil and exposure classes

Question: Are load tests on completed structures ever employed?

Question: Shear reinforcement for beam-column connections

Question: How do the code requirements get to the contractor?

Question: Punching shear check for shear wall foundations

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