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Cooling and Insulating Systems for Mass Concrete --`````,,,,``,,,`,,```,`,,,,,`-`-`,,`,,`,`,,` daneshlink.com ACI 207.4R-05 (Reapproved 2012) Cooling and Insulating Systems for Mass Concrete --`````,,,,``,,,`,,```,`,,,,,`-`-`,,`,,`,`,,`--- Reported by ACI Committee 207 Copyright American Concrete Institute Provided by IHS under license with ACI Licensee=University of Texas Revised Sub Account/5620001114, User=wer, srdtgert No reproduction or networking permitted without license from IHS Not for Resale, 01/26/2015 01:17:36 MST Daneshlink.com daneshlink.com First printing October 2005 Cooling and Insulating Systems for Mass Concrete Copyright by the American Concrete Institute, Farmington Hills, MI. All rights reserved. This material may not be reproduced or copied, in whole or part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of ACI. The technical committees responsible for ACI committee reports and standards strive to avoid ambiguities, omissions, and errors in these documents. In spite of these efforts, the users of ACI documents occa- sionally find information or requirements that may be subject to more than one interpretation or may be incomplete or incorrect. Users who have suggestions for the improvement of ACI documents are requested to contact ACI. ACI committee documents are 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. Individuals who use this publication in any way assume all risk and accept total responsibility for the application and use of this information. All information in this publication is provided “as is” without warranty of any kind, either express or implied, including but not limited to, the implied warranties of merchantability, fitness for a particular purpose or non-infringement. --`````,,,,``,,,`,,```,`,,,,,`-`-`,,`,,`,`,,`--- ACI and its members disclaim liability for damages of any kind, including any special, indirect, incidental, or consequential damages, including without limitation, lost revenues or lost profits, which may result from the use of this publication. It is the responsibility of the user of this document to establish health and safety practices appropriate to the specific circumstances involved with its use. ACI does not make any representations with regard to health and safety issues and the use of this document. The user must determine the applicability of all regulatory limitations before applying the document and must comply with all applicable laws and regula- tions, including but not limited to, United States Occupational Safety and Health Administration (OSHA) health and safety standards. Order information: ACI documents are available in print, by download, on CD-ROM, through electronic subscription, or reprint and may be obtained by contacting ACI. Most ACI standards and committee reports are gathered together in the annually revised ACI Manual of Concrete Practice (MCP). American Concrete Institute 38800 Country Club Drive Farmington Hills, MI 48331 U.S.A. Phone: 248-848-3700 Fax: 248-848-3701 www.concrete.org ISBN 0-087031-191-3 Copyright American Concrete Institute Provided by IHS under license with ACI Licensee=University of Texas Revised Sub Account/5620001114, User=wer, srdtgert No reproduction or networking permitted without license from IHS Not for Resale, 01/26/2015 01:17:36 MST Daneshlink.com daneshlink.com ACI 207.4R-05 (Reappoved 2012) Cooling and Insulating Systems for Mass Concrete Reported by ACI Committee 207 Stephen B. Tatro Chair Jeffrey C. Allen Robert W. Cannon Barry D. Fehl Gary R. Mass Terrence E. Arnold Teck L. Chua Rodney E. Holderbaum Tibor J. Pataky Randall P. Bass Eric J. Ditchey Allen J. Hulshizer Ernest K. Schrader J. Floyd Best Timothy P. Dolen David E. Kiefer Gary P. Wilson Anthony A. Bombich The need to control volume change induced primarily by temperature 2.2—Heat exchange change in mass concrete often requires cooling and insulating systems. 2.3—Batch water This report reviews precooling, postcooling, and insulating systems. A sim- 2.4—Aggregate cooling plified method for computing the temperature of freshly mixed concrete cooled by various systems is also presented. 2.5—Cementitious materials 2.6—Heat gains during concreting operations Keywords: cement content; coarse aggregate; creep; formwork; heat of 2.7—Refrigeration plant capacity hydration; mass concrete; modulus of elasticity; precooling; postcooling; 2.8—Placement area pozzolan; restraint; specific heat; strain; stress; temperature rise; tensile strength; thermal conductivity; thermal diffusivity; thermal expansion; thermal Chapter 3—Postcooling systems, p. 9 gradient; thermal shock. 3.1—General 3.2—Embedded pipe CONTENTS Chapter 1—Introduction, p. 2 3.3—Refrigeration and pumping facilities 1.1—Scope and objective 3.4—Operational flow control 1.2—Historical background 3.5—Surface cooling 1.3—Types of structures and temperature controls 1.4—Construction practices for temperature control Chapter 4—Surface insulation, p. 11 4.1—General 1.5—Instrumentation 4.2—Materials 4.3—Horizontal surfaces Chapter 2—Precooling systems, p. 3 2.1—General 4.4—Formed surfaces 4.5—Edges and corners 4.6—Heat absorption from light energy penetration ACI Committee Reports, Guides, Manuals, and Commentaries 4.7—Geographical requirements 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 Chapter 5—References, p. 14 significance and limitations of its content and recommendations 5.1—Referenced standards and reports and who will accept responsibility for the application of the 5.2—Cited references 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. ACI 207.4R-05 supersedes 207.4R-93 (Reapproved 1998) and became effective Reference to this document shall not be made in contract August 15, 2005. documents. If items found in this document are desired by the Copyright © 2005, American Concrete Institute. Architect/Engineer to be a part of the contract documents, they All rights reserved including rights of reproduction and use in any form or by any shall be restated in mandatory language for incorporation by 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 the Architect/Engineer. or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors. --`````,,,,``,,,`,,```,`,,,,,`-`-`,,`,,`,`,,`--- Copyright American Concrete Institute 1 Provided by IHS under license with ACI Licensee=University of Texas Revised Sub Account/5620001114, User=wer, srdtgert No reproduction or networking permitted without license from IHS Not for Resale, 01/26/2015 01:17:36 MST Daneshlink.com daneshlink.com 2 COOLING AND INSULATING SYSTEMS FOR MASS CONCRETE (ACI 207.4R-05) CHAPTER 1—INTRODUCTION Cooling was also started in this latter zone coincidently with 1.1—Scope and objective the placing of concrete in each new lift. The need to control volume change induced primarily by In the 1960s, the Corps of Engineers began the practice of temperature change in mass concrete often requires cooling starting, stopping, and restarting the cooling process based and insulating systems. This report discusses three construction on temperatures measured with embedded resistance procedures used to control temperature changes in concrete thermometers. At Dworshak Dam and at the Ice Harbor structures: precooling of materials, postcooling of in-place Additional Power House Units, the cooling water was concrete by embedded pipes, and surface insulation. Other stopped when the temperature of the concrete near the pipes design and construction practices, such as selection of began to drop rapidly after reaching a peak. Within 1 to 3 days cementing materials, aggregates, chemical admixtures, later, when the temperature would rise again to the previous cement content, or strength requirements, are not within the peak temperature, cooling would be started again to produce scope of this report. controlled, safe cooling. The objective of this report is to offer guidance on the Generally, arch dams were constructed with postcooling selection and application of these procedures for reducing systems to expedite the volume change of the mass concrete thermal cracking in all types of concrete structures. for joint grouting. The first roller-compacted concrete (RCC) arch dam was Knellpoort Dam in South Africa, completed in 1.2—Historical background 1988. Due to the height and rapid construction of RCC arch Major developments in cooling and insulating systems for dams, design engineers paid close attention to the heat-of- concrete began with postcooling systems for dams. Later hydration issues due to their effect on the final stress state of gains were made in developing precooling methods. The use the dam. In China, several arch dams have been completed, including Shapai Dam near Chengdu, China, which was the of natural cooling methods has increased with the use of world’s highest until 2004. At Shapai Dam, and others since, better analytical methods to compute thermal performance. cooling pipes were embedded between some of the RCC lifts Similarly, insulating systems expanded
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