Introduction

Basic Relationship

Chemical Admixtures

Background Data

Design Parameters

Design Procedure

BACKGROUND DATA

ACI 211.1-91, Reapproved 2009, states: "To the extent possible, selection of concrete proportions should be based on test data or experience with the materials actually to be used. The following information for available materials will be useful:

• Sieve analyses of fine and coarse aggregates.

• Unit weight of coarse aggregate.

• Bulk specific gravities and absorption of aggregates.

• Mixing-water requirements of concrete developed from experience with available aggregates.

• Relationship between strength and water-cement ratio or ratio of water-to-cement plus other cementitious materials.

• Specific gravity of Portland cement and other cementitious materials, if used.

• Optimum combination of coarse aggregates to meet the maximum density grading for mass concrete.

• Estimate of proportions of mix for preliminary design."