Guide for Measuring, Mixing, Transporting, and Placing Concrete

Description

This guide outlines procedures for achieving good results in measuring and mixing ingredients for concrete, transporting it to the site, and placing it. The first six chapters are general and apply to all types of projects and concrete. The following four chapters deal with preplaced-aggregate concrete, underwater placing, pumping, and conveying on belts. The concluding three chapters deal with heavyweight, radiation-shielding concrete, lightweight concrete, and volumetric-measuring and continuous-mixing concrete equipment.

When preparing this guide, ACI Committee 304 followedthis philosophy:

• Progress in improvement of concrete construction is better served by the presentation of high standards rather than common practices;

• In many, if not most, cases, practices resulting in the production and placement of high-quality concrete can be performed as economically as those resulting in poor concrete. Many of the practices recommended in this document improve concrete uniformity as well as quality, yielding a smoother operation and higher production rates, both of which offset potential additional cost; and

• Anyone planning to use this guide should have a basic knowledge of the general practices involved in concrete work. If more specific information on measuring ,mixing, transporting, and placing concrete is desired, the reader should refer to the list of references given at the end of this document, and particularly to the work of the U.S. Bureau of Reclamation (1981), the U.S. Department of Commerce (1966), the Corps of Engineers (1994a), ASTM C 94, ACI 311.1R, and ACI 318.To portray more clearly certain principles involved in achieving maximum uniformity, homogeneity, and quality of concrete in place, figures that illustrate good and poor practices are also included in this guide.