ACI 232.1R-00 Use of Raw or Processed Natural Pozzolans in Concrete Reported by ACI Committee 232 Paul J. Tikalsky* Chairman

Morris V. Huffman* Secretary

Gregory M. Barger*

Allen J. Hulshizer

Sandor Popovics

Bayard M. Call

Tarif M. Jaber

Jan Prusinski

Ramon L. Carrasquillo

Jim S. Jensen

Dan Ravina

James E. Cook

Elizabeth S. Jordan

Douglas W. Deno

Paul Klieger*

*

D. V. Reddy Harry C. Roof

George R. Dewey

Steven H. Kosmatka

Della Roy

Edwin R. Dunstan, Jr.

Ronald L. Larson

John M. Scanlon‡

William E. Ellis, Jr.

V. M. Malhotra

Ava Shypula*

Dean Golden

Oscar Manz*

Peter G. Snow

Karen A. Gruber

*

*

Richard C. Mielenz

G. Terry Harris, Sr.

Tarun R. Naik

*

†

R. Douglas Hooton

Robert Sparacino

Bryant Mather

William Halczak

Terry Patzias

*

Michael D. A. Thomas Samuel S. Tyson Orville R. Werner, II

*

Subcommittee members for this report. chairman for this report. ‡ Deceased. Note: Special thanks is extended to P. K. Mehta and Caijun Shi for their help with this document. †Subcommittee

This report provides a review of the state-of-the-art use of raw or processed natural pozzolans in concrete and an overview of the properties of natural pozzolans and their proper use in the production of hydraulic-cement concrete. Natural pozzolans mixed with lime were used in concrete construction long before the invention of portland cement because of their contribution to the strength of concrete and mortar. Today, natural pozzolans are used with portland cement not only for strength, but also for economy and beneficial modification of certain properties of fresh and hardened portland-cement concrete.

ACI Committee Reports, Guides, Standard Practices, and Commentaries are intended for guidance in planning, designing, executing, and inspecting construction. This document is intended for the use of individuals who are competent to evaluate the significance and limitations of its content and recommendations and who will accept responsibility for the application of the material it contains. The American Concrete Institute disclaims any and all responsibility for the stated principles. The Institute shall not be liable for any loss or damage arising therefrom. Reference to this document shall not be made in contract documents. If items found in this document are desired by the Architect/Engineer to be a part of the contract documents, they shall be restated in mandatory language for incorporation by the Architect/Engineer.

This report contains information and recommendations concerning the selection and use of natural pozzolans generally conforming to the applicable requirements of ASTM C 618 and CSA A23.5. Topics covered include the effect of natural pozzolans on concrete properties, a discussion of quality control and quality assurance, and guidance regarding handling and use of natural pozzolans in specific applications. References are provided that offer more information on each topic. Keywords: alkali-silica reaction; cement; concrete; concrete strength; diatomaceous earth; lime; natural pozzolan; pozzolan; pozzolanic activity; sulfate attack (on concrete).

CONTENTS Chapter 1—General, p. 232.1R-2 1.1—History 1.2—Definition of a natural pozzolan 1.3—Chemical and mineralogical composition 1.4—Classification 1.5—Examples ACI 232.1R-00 supersedes ACI 232.1R-94 and became effective December 6, 2000. Copyright  2001, American Concrete Institute. All rights reserved including rights of reproduction and use in any form or by any means, including the making of copies by any photo process, or by electronic or mechanical device, printed, written, or oral, or recording for sound or visual reproduction or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors.

232.1R-1

232.1R-2

ACI COMMITTEE REPORT

1.6—Chemical and physical properties 1.7—Uses Chapter 2—Effects of natural pozzolan on concrete properties, p. 232.1R-8 2.1—Concrete mixture proportions 2.2—Properties of fresh concrete 2.3—Properties of hardened concrete Chapter 3—Specifications, test methods, quality control, and quality assurance, p. 232.1R-16 3.1—Introduction 3.2—Chemical requirements 3.3—Physical requirements 3.4—General specification provisions 3.5—Methods of sampling and testing 3.6—Quality control and quality assurance Chapter 4—Concrete production using natural pozzolans, p. 232.1R-18 4.1—Storage 4.2—Batching Chapter 5—Concrete applications for natural pozzolans, p. 232.1R-19 5.1—Concrete masonry units 5.2—Concrete pipes 5.3—Prestressed concrete products 5.4—Mass concrete Chapter 6—Other uses of natural pozzolans, p. 232.1R-20 6.1—Grouts and mortars 6.2—Controlled low-strength materials Chapter 7—References, p. 232.1R-21 7.1—Referenced standards and reports 7.2—Cited references CHAPTER 1—GENERAL 1.1—History Lime and limestone are among the oldest materials used by mankind for construction purposes. Structures built of limestone include the pyramids of Egypt. Long before the invention of portland cement in 1824, mortars and concretes composed of mixtures and fillers and raw or heat-treated lime were used for construction throughout the world (Malinowski 1991). Malinowski et al. (1993) report that the oldest example of hydraulic binder, dating from 5000-4000 B.C., was a mixture of lime and natural pozzolan, a diatomaceous earth from the Persian Gulf. The next oldest reported use was in the Mediterranean region. The pozzolan was volcanic ash produced from two volcanic eruptions: one, sometime between 1600 and 1500 B.C. on the Aegean Island of Thera, now called Santorin, Greece; the other in 79 A.D. at Mt. Vesuvius on the bay of Naples, Italy. Both are volcanic ashes or pumicites consisting of almost 80% volcanic glass (pumice and obsidian). According to the Roman engineer Marcus Vitruvius Pollio (Vitruvius Pollio 1960), who lived in the first century B.C.,

the cements made by the Greeks and the Romans were of superior durability, because “neither waves could break, nor water dissolve” the concrete. In describing the building techniques of masonry construction, he indicated that the Romans developed superior practices of their own from the techniques of the Etruscans and the Greeks. The Greek masons discovered pozzolan-lime mixtures sometime between 700-600 B.C. and later passed their use of concrete along to the Romans in about 150 B.C. During the 600 years of Roman domination, the Romans discovered and developed a variety of pozzolans throughout their empire (Kirby et al. 1956). During archaeological excavations in the 1970s at the ancient city of Camiros on the Island of Rhodes, Greece, an ancient water-storage tank having a capacity of 600 m3 (785 yd3) was found. Built in about 600 B.C., it was used until 300 B.C. when a new hydraulic system with an underground water tank was constructed. For almost three millennia this water tank has remained in very good condition, according to Efstathiadis (1978). Examination of the materials used for this structure revealed that the concrete blocks and mortar used were made out of a mixture of lime, Santorin earth, fine sand (