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Found 23 FAQs.

Question: How do the requirements of placing affect the selection of proportions of aggregates and cementi...

Question: How is the selection of mixture proportions affected by the materials to be used and the placing...

Question: What nominal maximum sizes of aggregate are recommended?

Question: The basic approach used in the ACI mixture proportioning method

Question: How does the relative amount of each ingredient used in concrete influence the properties of con...

Question: Are the proportions of ingredients inter-related to produce concrete of a given workability?

Question: Aggregate blending

Question: What range in slump is recommended for various types of construction?

Question: Air content common limits

Question: The effect of aggregate shape on concrete strength

Question: The effect of aggregate grading on concrete strength

Question: What correction should be made for absorbed water and surface water carried by the aggregates?

Question: Mixture design and strength submittals

Question: What does ACI recommend regarding water-cement (w/c) ratios or admixtures to improve workability...

Question: Pozzolans in mass concrete

Question: What water-cementitious material ratio should be used for a particular job when strength require...

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

Question: What allowance should be made for strengths where air-entrained concrete is to be used?

Question: What is the basis of proportioning to ensure concrete of the desired weather resistance?

Question: When does the slump test provide a useful indication of workability?

Question: What test is available to evaluate the behavior of no-slump concrete as it is vibrated?

Question: Why is combined aggregate grading used?

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