ACI 506.2-13 - Specification for Shotcrete.pdf

ACI 506.2-13

Specification for Shotcrete An ACI Standard

Reported by ACI Committee 506

Copyright American Concrete Institute Provided by IHS under license with ACI No reproduction or networking permitted without license from I HS

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First Printing January 2014 ®

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Specification for Shotcrete 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 occasionally 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 via the errata website at www.concrete.org/committees/errata.asp. Proper use of this document includes periodically checking for errata for the most up-to-date revisions. 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 i n 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, l ost 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 regulations, including but not limited to, United States Occupational Safety and Health Administration (OSHA ) health and safety standards. Participation by governmental representatives in the work of the American Concrete Institute and in the development of Institute standards does not constitute governmental endorsement of ACI or the standards that it develops. 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.

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ACI 506.2-13 Specification for Shotcrete An ACI Standard

Reported by ACI Committee 506 Marc Jolin*, Secretary

Lawrence J. Totten, Chair

Jon B. Ardahl * Lars Balck, Jr. Michael Ballou Nemkumar Banthia Chris D. Breeds Wern-Ping Nick Chen Scott R. Cumming * Jean-Francios Dufour Jill E. Glassgold Charles S. Hanskat * Warren L. Harrison

Thomas Hennings Kristian Loevlie Mark R. Lukkarila Gregory S. McKinnon Jeffrey L. Novak H. Celik Ozyildirim Harvey W. Parker Ryan E. Poole John H. Pye James A. Ragland* Venkataswamy Ramakrishnan

Raymond C. Schallom, III Raymond J. Schutz Philip T. Seabrook † W. L. Snow, Sr. * Peter C. Tatnall* Curtis White Peter T. Yen George Yoggy Lihe Zhang Christopher M. Zynda

*

Consulting members Merlyn Isaak Richard A. Kaden Roman Malinowski Dudley R. Morgan

CONTENTS (mandatory portion follows)

Task group members who produced this specicat ion. Task group Chair who produced this specicat ion.

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PART 1—GENERAL, p. 2 1.1—Scope, p. 2 1.2—Denitions, p. 2 1.3—Referenced standards, p. 2 1.4—Submittals, p. 3 1.5—Preconstruction testing by Contractor, p. 4 1.6—Testing during construction, p. 4 1.7—Delivery, storage, and handling, p. 5

This specication contains the construction requirements for the application of shotcrete. Both wet- and dry-mixture shotcrete are addressed, as well as ber-reinforced shotcrete. The minimum standard for materials, properties, testing, and application are covered. The materials, processes, quality control measures, and inspections described in this specication should be tested, monitored, or performed as applicable only by individuals holding the appro priate ACI certications or equivalent. Keywords: dry-mixture shotcrete; ber-reinforced shotcrete; nozzleman; qualication; quality control; quality assurance; shooting; wet-mixture shotcrete.

PART 2—PRODUCTS, p. 5 2.1—Materials, p. 5 2.2—Packaged shotcrete materials, p. 5 2.3—Fiber-reinforced shotcrete, p. 5 2.4—Shotcrete properties, p. 5 2.5—Proportioning, p. 6 2.6—Batching, mixing, and delivery, p. 6 PART 3—EXECUTION, p. 6 3.1—Preparation of surface to receive shotcrete, p. 6 3.2—Joints, p. 6 3.3—Alignment control, p. 6 3.4—Application, p. 6

ACI Committee Reports, Guides, 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 signicance 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.

ACI 506.2-13 supersedes ACI 506.2-95 and was adopted on October 29, 2013 and published in January 2014. Copyright © 2014 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 reproduc tion or for use in any knowledge or retrieval system or device, unless permission in writing is obtained from the copyright proprietors.

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Subcommittee member Donald M. McPhee

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SPECIFICATION FOR SHOTCRETE (ACI 506.2-13)

3.5—Finish, p. 7 3.6—Curing, p. 7 3.7—Protection, p. 8 3.8—Tolerances, p. 8 3.9—Repair of shotcrete, p. 8 3.10—Acceptance of Work, p. 8 (nonmandatory portion follows)

NOTES TO SPECIFIER, p. 8 General notes, p. 8 FOREWORD TO CHECKLISTS, p. 9 CHECKLIST REFERENCES, p. 12 (mandatory portion follows) PART 1—GENERAL 1.1—Scope —This Reference Specication covers 1.1.1 Work specied the requirements for shotcrete as specied by the Archi tect/Engineer. Included are the requirements for materials; proportioning; and application of structural and nonstructural shotcrete, including structural and nonstructural berreinforced shotcrete. 1.1.2 Units —Values in this specication are stated in inch pound units. A companion specication in SI units is also available. 1.2—Definitions accepted —determined to be satisfactory by Owner or Architect/Engineer. Architect/Engineer —the architect, engineer, architectural rm, engineering rm, or architectural and engineering rm issuing Contract Documents or administering the Work under Contract Documents, or both. Contract Documents —set of documents supplied by Owner to Contractor as the basis for construction; these documents contain contract forms, contract conditions, specications, drawings, addenda, and contract changes. Contractor —the person, rm, or corporation with whom the Owner enters into an agreement for construction of the Work. ber-reinforced shotcrete (FRS) ––shotcrete containing discontinuous discrete bers. gun nish ––undisturbed nal layer of shotcrete as applied from a nozzle without further nishing. overspray —waste shotcrete material deposited away from intended receiving surface. Owner —the corporation, association, partnership, individual, public body, or authority with whom the Contractor enters into an agreement and for whom the Work is provided. permitted —accepted by or acceptable to Architect/Engineer; usually pertains to a request by Contractor, or when specied in Contract Documents. predampening —in the dry-mixture process, adding water to the aggregate before mixing to bring its moisture content to a specied amount, usually 3 to 6 percent. ` , , ` ` ` , , , , ` ` ` ` ` ` , , ` , , ` , ` , , ` -


quality assurance —actions taken by Owner or Owner’s representative to assure Work done and materials provided are in accordance with Contract Documents. quality control —actions taken by the Contractor to assure that Work meets requirements of Contract Documents. Reference Specication —a standardized mandatorylanguage document prescribing materials, dimensions, and workmanship, incorporated by reference in Contract Documents. mandatoryReference Standards —standardized language documents of a technical society, organization, or association, including building codes of local or state author ities, which are referenced by the Contract Documents. required —stipulated in this specication or the Contract Documents. rod nish ––a sharp-edged cutting screed to be used to trim shotcrete forms or ground wires. shotcrete —concrete or mortar conveyed through a hose and pneumatically projected at high velocity onto a surface to achieve compaction. structural shotcrete —plain or reinforced shotcrete in a member that is part of a structural system required to transfer gravity and/or lateral loads along a path to the ground. submit —provide to Architect/Engineer for review. submittal —documents or materials provided to Architect/Engineer for review and/or acceptance. Work —the entire construction or separately identiable parts thereof required to be furnished under Contract Documents.

1.3—Referenced standards Standards of ASTM International cited in this Specication are listed by name and designation, including year. ASTM International A185/A185M-07—Standard Specication for Steel Welded Wire Reinforcement, Plain, for Concrete A615/A615M-12—Standard Specication for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement A706/A706M-09b—Standard Specication for LowAlloy Steel Deformed and Plain Bars for Concrete Reinforcement C33/C33M-13—Standard Specication for Concrete Aggregates C78/C78M-10e1—Standard Test Method for Flexural Strength of Concrete (Using Simple Beam with Third Point Loading C42/C42M-13—Standard Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete C94/C94M-13a—Standard Specication for ReadyMixed Concrete C127-12—Standard Test Method for Density, Relative Density (Specic Gravity), and Absorption of Coarse Aggregate C128-12—Standard Test Method for Density, Relative Density (Specic Gravity), and Absorption of Fine Aggregate

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C150/C150M-12—Standard Specication for Portland Cement C171-07—Standard Specication for Sheet Materials for Curing Concrete C231/C231M-10—Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method C309-11—Standard Specication for Liquid MembraneForming Compounds for Curing Concrete C494/C494M-13—Standard Specication for Chemical Admixtures for Concrete C457/C457M-12—Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in Hardened Concrete C618-12a—Standard Specication for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete C642-13—Standard Test Method for Density, Absorption, and Voids in Hardened Concrete C685/C685M-11—Standard Specication for Concrete made by Volumetric Batching and Continuous Mixing C928/C928M-09—Standard Specication for Packaged, Dry, Rapid-Hardening Cementitious Materials for Concrete Repairs C989/C989M-12a—Standard Specication for Slag Cement for Use in Concrete and Mortars C1059/C1059M-99 (2008)—Standard Specication for Latex Agents for Bonding Fresh to Hardened Concrete. C1064/C1064M-12—Standard Test Method for Temperature of Freshly Mixed Hydraulic -Cement Concrete C1077-13b—Standard Practice for Laboratories Agency Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Testing Agency Evaluation C1116/C1116M-10a—Standard Specication for FiberReinforced Concrete C1140/C1140M-11—Standard Practice for Preparing and Testing Specimens from Shotcrete Test Panels C1141/C1141M-08—Standard Specication for Admixtures for Shotcrete C1240-12—Standard Specication for Silica Fume Used in Cementitious Mixtures C1315-11—Standard Specication for Liquid MembraneForming Compounds Having Special Properties for Curing and Sealing Concrete C1385/C1385M-10—Standard Practice for Sampling Materials for Shotcrete C1399/C1399M-10—Standard Test Method for Obtaining Average Residual-Strength for Fiber-Reinforced Concrete C1436-08—Standard Specication for Materials for Shotcrete C1480/C1480M-12—Standard Specication for Pack aged, Pre-Blended, Dry, Combined Materials for Use in Wet or Dry Shotcrete Application C1550-12a—Standard Test Method for Flexural Toughness of Fiber Reinforced Concrete (Using Centrally Loaded Round Panel) C1583/C1583M-13—Standard Test Method for Tensile Strength of Concrete Surfaces and the Bond Strength or Tensile Strength of Concrete Repair and Overlay Materials by Direct Tension (Pull off Method)


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C1602/C1602M-12—Standard Specication for Mixing Water Used in the Production of Hydraulic Cement Concrete C1604/C1604M-05(2012)—Standard Test Method for Obtaining and Testing Drilled Cores of Shotcrete C1609/C1609M-12—Standard Test Method for Flexural Performance of Fiber-Reinforced Concrete (Using Beam with Third-Point Loading)

1.4—Submittals 1.4.1 Submit data showing compliance with requirements specied in 1.4.1.1 through 1.4.1.17. Where available, submit material safety data sheets (MSDS) for all materials. 1.4.1.1 Submit shotcrete mixture proportions. Submittals shall show constituent proportions by mass in the case of batching by weight or proportions by volume in the case of volumetric batching. For prepackaged materials meeting ASTM C1480/C1480M, submit suppliers’ technical data showing compliance with requirements. 1.4.1.2 Submit compressive strength test results and, if ber-reinforced shotcrete (FRS) is specied, exural strength and exural parameters in accordance with the Contract Documents. 1.4.1.3 Submit water-cementitious materials ratio (w/cm) for wet-mixture shotcrete only. 1.4.1.4 Submit admixture types, brand names, producers, manufacturer’s technical data sheets describing technical properties and performance in shotcrete and showing compatibility with the project cementitious materials. 1.4.1.5 Submit cementitious materials types, test reports showing manufacturing location, and compliance with applicable ASTM standards. 1.4.1.6 Submit aggregate source, producers’ names, gradations, specic gravities, compliance with ASTM C33/C33M, and evidence that this data is not more than 1 year old. 1.4.1.7 Submit aggregate absorption in accordance with ASTM C127 for coarse aggregate and ASTM C128 for ne aggregate. 1.4.1.8 Submit qualications and experience of the proposed workers including the supervisor, nozzlemen, and crew. For structural or FRS shotcrete, submit evidence of ACI certication of nozzlemen proposed for the Work. 1.4.1.9 For application of structural shotcrete, submit proof of experience for the Contractor and the shotcrete crew foreman to include at least ve projects of similar size and complexity. Proof shall include a description of previous project’s size; density of reinforcing materials; volume of shotcrete placed; and the name, address, and current phone number of person(s) representing the Owner or Architect/ Engineer. For other applications of shotcrete, submit proof that the Contractor and crew foreman have at least 3 years’ experience in that type of shotcrete application. 1.4.1.10 For nonpotable water, submit the source and reports conrming compliance with ASTM C1602/C1602M. 1.4.1.11 If FRS is specied, submit ber material, length or lengths, and ber content. 1.4.1.12 Submit mill certicate showing conformance for reinforcing steel or welded wire reinforcement.


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1.4.1.13 When specied, provide test reports for shotcrete boiled absorption and volume of permeable voids showing compliance with the specied properties. 1.4.1.14 If hydration control admixtures are proposed by the Contractor, the submittal shall be in accordance with 1.4.1.4 and the use of such admixture shall be assessed in the prequalication test program in 1.5.1. 1.4.1.15 Submit repair procedure for shotcrete defects for the Architect/Engineer’s acceptance. The submittal shall include proposed materials, surface preparation, bonding procedures, and nal surface nish. 1.4.1.16 Submit curing materials and curing procedures for shotcrete. 1.4.1.17 Submit name of proposed Contractor’s testing agency and documentation of the agency’s certication to ASTM C1077.

1.5—Preconstruction testing by Contractor 1.5.1 Complete preconstruction testing required by Contract Documents. 1.5.1.1 Testing of materials required as part of the preconstruction program shall be conducted by the Contractor’s testing agency. Agency selection shall be acceptable to the Architect/Engineer. 1.5.1.2 Notify the Architect/Engineer of the time and place of preconstruction testing and provide Architect/Engineer with copies of testing reports. 1.5.1.3 Construct preconstruction test panels for examination by Architect/Engineer prior to project shotcrete placement. Preparation and testing shall comply with ASTM C1140/C1140M. Mixture proportions shall meet the requirements of 2.5. 1.5.1.4 Construct test panels for each proposed shotcrete mixture, each anticipated shooting orientation, and each proposed nozzleman. 1.5.1.5 Testing required as part of the preconstruction test program shall be provided by the Contractor’s testing agency. 1.5.1.6 Test specimens cored or sawed from the panels for compliance with the specied compressive strength in accordance with ASTM C1604/C1604M and, when specied, exural strength shall be in accordance with ASTM C78/C78M with beams obtained by ASTM C42. 1.5.1.7 Complete testing to determine other specied shot crete properties. 1.5.1.8 When FRS is specied, test exural performance using beams sawed from test panels for exural strength in accordance with ASTM C1609/C1609M and for residual strength in accordance with ASTM C1609/C1609M or C1399/C1399M. For toughness, test in accordance with ASTM C1550. 1.5.1.9 When the degree of encasement of reinforcement or severity of defects within the shotcrete sample is specied, prepare additional panels with the specied reinforcement. Core panels in accordance with ASTM C1140/C1140M. Cores containing reinforcement shall be provided to the Architect/Engineer for visual examination to determine ` , , ` ` ` , , , , ` ` ` ` ` ` , , ` , , ` , ` , , ` -


acceptance. Cores for examination shall have a minimum diameter of 3.75 in. and be the full thickness of the panel. 1.5.1.10 When the initial prequalication test panel is rejected, a second panel may be shot and tested. If this panel is acceptable, Work may proceed. If the second panel is not acceptable, the Contractor shall change procedures, mixture proportions, nozzlemen, or shotcrete equipment as necessary before repeating the preconstruction testing. Do not proceed with Work until preconstruction test results are satisfactory to Architect/Engineer. 1.5.2 Preplacement verication 1.5.2.1 The forms shall be to line and grade and have adequate support to remain rigid during shooting. 1.5.2.2 The formwork, substrata preparation, and cleanliness shall comply with Contract Documents. 1.5.2.3 The reinforcement type, size, grade, amount, placement, cleanliness, and other requirements shall comply with Contract Documents. 1.5.2.4 The placement of and clearance around reinforcement shall permit complete encasement of reinforcement with shotcrete. 1.5.2.5 The mixture proportions shall be the same as the approved submittal.

1.6—Testing during construction 1.6.1 Quality assurance by Owner or Architect/Engineer 1.6.1.1 The quality assurance testing agency shall be certied to ASTM C1077. 1.6.1.2 The Contractor shall provide the Owner and the quality assurance testing agency with 2 working days’ notice prior to the commencement of shotcreting. 1.6.1.3 The Owner’s quality assurance testing agency will inspect, sample, and test materials and shotcrete production as required by the Owner. When it appears that material or workmanship fails to comply with the Contract Documents, the agency will immediately report deciencies to the Owner, Architect/Engineer, and Contractor. 1.6.2 Testing shotcrete 1.6.2.1 Test samples —Sample shotcrete in accordance with ASTM C1385/C1385M. The Contractor is responsible for the curing and protection of test panels on site prior to the time that they are transported to the testing agency’s laboratory. 1.6.2.2 Compressive strength samples —Obtain test specimens from job-site test panels unless Contract Documents stipulate that in-place shotcrete test specimens are to be used. 1.6.2.3 Flexural strength or other exural parameter samples —For exural strength, exural parameter, or toughness requirements of FRS, only test panels shall be used. 1.6.2.4 Air content of mixture —When wet-mixture shotcrete is used and air entrainment is required, test for air content at discharge from the truck chute in accordance with ASTM C231/C231M prior to placement. Testing of dry-mix shotcrete air content as shot is difcult and there is no plastic state ASTM test method for this. Instead, it is recommended to use hardened air voids tests by ASTM C457/C457M. 1.6.2.5 Temperature of shotcrete mixture —Determine the temperature of the mixture using material sampled prior



to discharge from the truck chute into the pump for wetmixture shotcrete or the shotcrete machine for dry-mix shotcrete. Testing shall be completed in accordance with ASTM C1064/C1064M. 1.6.3 Test panels 1.6.3.1 Construct a test panel for each mixture, each nozzleman, and each work day or for every 50 yd 3 placed, whichever results in the most panels. The face dimensions of a test panel shall be a minimum of 16 x 16 in. with a minimum depth of 5 in. For toughness testing in accordance with ASTM C1550, the face dimension shall be 30.5 in. in diameter and 3 in. thick. Shoot test panels in a vertical orientation only unless otherwise specied. 1.6.3.2 Condition test panels in accordance with ASTM C1140/C1140M until transported to the testing agency’s laboratory. 1.6.3.3 Obtain test specimens from test panels using procedures outlined in ASTM C1140/C1140M or C1604/ C1604M. Cores shall be a nominal 3 in. diameter. 1.6.3.4 Test shotcrete specimens for compliance in accor dance with ASTM C1604/C1604M for compressive strength. 1.6.3.5 When specied, test boiled absorption and volume of permeable voids in accordance with ASTM C642. 1.6.3.6 When specied, test FRS specimens for exural parameters in accordance with 1.5.1.8. 1.6.4 Testing in-place shotcrete 1.6.4.1 Obtain core specimens from locations designated by Architect/Engineer in accordance with ASTM C1140/ C1140M. 1.6.4.2 Unless otherwise specied, condition test speci mens by soaking as specied in ASTM C1604/C1604M. 1.6.4.3 Test specimens in accordance with 1.6.2. 1.6.5 Testing shotcrete bond to substrate —If required by Contract Documents, conduct bond testing of the shotcrete to the substrate in accordance with ASTM C1583/C1583M. 1.6.6 Reporting of quality assurance test results —Provide copies of any test results generated for quality assurance to the Contractor, Owner, Architect/Engineer, and concrete supplier.

1.7—Delivery, storage, and handling Deliver, store, and handle materials to prevent contamination, segregation, corrosion, or damage. Store and protect liquid admixtures as required to prevent evaporation and freezing. PART 2—PRODUCTS 2.1—Materials —Unless otherwise specied, cement shall 2.1.1 Cement comply with ASTM C150/C150M. 2.1.2 Supplementary cementitious materials —When specied, supplementary cementitious materials shall comply with ASTM C618 for y ash and natural pozzolans, ASTM C989/C989M-12a for slag cement, and ASTM C1240 for silica fume. 2.1.3 Aggregate —Unless otherwise specied, aggregates shall comply with ASTM C33/C33M for normalweight Copyright American Concrete Institute Provided by IHS under license with ACI No reproduction or networking permitted without license from I HS

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aggregates. The combined aggregate gradation shall comply with grading No. 2 of ASTM C1436, unless otherwise specied. —Unless otherwise specied, water shall be 2.1.4 Water potable. When nonpotable water is permitted in Contract Documents, water shall comply with ASTM C1602/ C1602M, except that wash water shall not be permitted unless accepted by Architect/Engineer. 2.1.5 Admixtures —When admixtures are permitted or required, the admixtures shall comply with ASTM C1141/ C1141M or, for hydration control admixtures, with ASTM C494/C494M. 2.1.6 Fibers —When FRS is specied, bers shall be the types, material, and sizes required by Contract Documents. Unless otherwise specied, they shall conform to ASTM C1116/C1116M. —Reinforcement shall be the grades, 2.1.7 Reinforcement types, and sizes required by the Contract Documents and, unless otherwise specied, shall conform to one of the following: a) Deformed steel reinforcement: ASTM A615/A615M; b) Welded wire reinforcement: ASTM A185/A185M; c) Weldable reinforcement: ASTM A706/A706M. 2.1.8 Curing materials 2.1.8.1 Sheet materials —Unless otherwise specied, sheet materials for curing shall comply with ASTM C171. 2.1.8.2 Curing compounds —Unless otherwise specied, curing compounds shall comply with ASTM C309 or C1315. Volatile organic compounds (VOC) content shall be in compliance with local air quality standards if those requirements are more stringent. 2.1.8.3 Do not use curing materials that cause stains for shotcrete having an architectural nish.

2.2—Packaged shotcrete materials When permitted, packaged, preblended, dry combined materials shall comply with ASTM C1480/C1480M. 2.3—Fiber-reinforced shotcrete Unless otherwise specied, FRS shall comply with ASTM C1116/C1116M. 2.4—Shotcrete properties 2.4.1 Shotcrete properties shall comply with the require ments of Contract Documents. 2.4.2 Where Contract Documents do not specify properties, the 28 day compressive strength shall be 4000 psi minimum. The Compressive strength shall be assessed in accordance with ACI 301. 2.4.3 Where Contract Documents specify FRS, the ex ural strength shall be a minimum of 400 psi at 28 days. 2.4.4 Air content for shotcrete shall be within the limits specied in the Contract Documents. Test frequency in accordance with the Contract Documents. 2.4.5 Water-soluble chloride ion content in mixture — Water-soluble chloride ion content shall not be greater than that specied in Contract Documents.


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2.4.6 Limitations on supplementary cementitious materials —Contract Documents shall specify limits, if any, on type and quantity of supplementary cementitious materials as dened in 2.1.2. 2.4.7 Shotcrete boiled absorption and volume of permeable voids —When required, conduct testing of shotcrete absorption and volume of permeable voids in accordance with ASTM C642. Specify acceptable limits in the Contract Documents. 2.4.8 When required for FRS, exural strength and exural parameters shall be in accordance with Contract Documents. 2.4.9 Bond strength —If required, specify the bond strength. Testing for bond strength, when specied, shall be on a minimum of three core samples and the strength shall be the average of all samples.

2.5—Proportioning Proportion shotcrete mixture by mass complying with ASTM C94/C94M, or by volume complying with ASTM C685/C685M, to satisfy the specied properties. For FRS, proportion in compliance with ASTM C1116/C1116M. 2.6—Batching, mixing, and delivery 2.6.1 Batch, mix, and deliver wet-mixture shotcrete in accordance with ASTM C94/C94M, C685/C685M, or C1116/C1116M as applicable. For dry-mixture, batching, mixing and delivering shall be in accordance with ASTM C685 /C685M or C1116/C1116M. 2.6.2 Predampening or other methods suitable for prewetting the dry materials shall be used with packaged preblended material for dry-mixture shotcrete. PART 3—EXECUTION 3.1—Preparation of surface to receive shotcrete 3.1.1 Earth —Surfaces shall be prepared to line and grade. Dampen surfaces immediately prior to shooting. No standing water shall be visible. 3.1.2 Concrete, masonry, and shotcrete —Remove all deteriorated, loose, unsound material or contaminants that will inhibit bonding. Receiving surface shall be dampened and allowed to dry to a saturated surface-dry (SSD) condition just prior to shotcrete application. 3.1.2.1 Chip surfaces to receive shotcrete to remove offsets causing abrupt changes in thickness. 3.1.2.2 Roughen receiving surfaces that have been sawcut. —Remove loose material, mud, or other 3.1.3 Rock foreign material that will inhibit bonding. Clean surface prior to shotcrete placement. Dampen surface in accordance with 3.1.1. 3.1.4 Reinforcement 3.1.4.1 Surface condition —The surface of the reinforcement shall be free of overspray or other deleterious materials that inhibit development of bond with the shotcrete. 3.1.4.2 Reinforcement laps —Laps shall be noncontact and shall be separated with a clearance of at least three times the diameter of the largest reinforcing bar; three times the maximum size aggregate; or 2 in., whichever is least, unless Copyright American Concrete Institute Provided by IHS under license with ACI No reproduction or networking permitted without license from I HS

otherwise specied. Bars spliced by noncontact lap splices in exural members shall not be spaced transversely farther apart than the smaller of 1/5 the required lap splice length and 6 in. The use of contact lap splices necessary for support of the reinforcing is permitted when approved by the Architect/Engineer. Lapped bars shall be in the same plane and parallel to the direction of shooting. Welded splices are permitted. 3.1.4.3 Secure reinforcement to prevent movement. The use of mechanical splices is permitted when approved. 3.1.5 Forms —Use material of adequate thickness for formwork to resist movement during shooting. Reinforce, secure, and brace forms to minimize the effects of vibration during shooting. Construct forms to allow escape of placement air, overspray, and rebound. Use form-release coating material on removable forms unless the formed surface is to subsequently receive an additional coating.

3.2—Joints 3.2.1 Construction joints —Taper construction joints at approximately 45 degrees from receiving surface. Form joints by cutting plastic shotcrete. Joints at slab intersections shall be made at 90 degrees. Roughen shotcrete in the joint face while it is still plastic. 3.2.2 Contraction joints —Where specied, place control joints as indicated in Contract Documents. Discontinue reinforcement at control joints unless otherwise specied. 3.3—Alignment control To establish thickness and plane of required surface, install taut ground wires or other means to guide the nozzleman. Install alignment control means at corners or offsets not established by forms. 3.4—Application 3.4.1 Placement techniques 3.4.1.1 Use the same shotcrete mixture and equipment that was used during nozzleman qualication and mixture design acceptance for the production shotcrete. 3.4.1.2 Use temporary coverings to protect adjacent surfaces from the deposit of overspray or impact from the nozzle stream. 3.4.1.3 Install sufcient lighting and ventilation to provide the shotcrete crew with a clear view of the shooting area. Suspend Work and adopt corrective measures if visibility is unsuitable for the application of quality shotcrete. 3.4.1.4 Provide a working surface that permits nozzlemen unobstructed access to the receiving surface. Place shotcrete rst in corners, recesses, and other areas where rebound or overspray cannot easily escape. 3.4.1.5 The supply of shotcrete material and air pressure at the nozzle shall be uniform, providing a steady, continuous ow of shotcrete with no detrimental surging or pulsing. Maintain the velocity and consistency of shotcrete exiting the nozzle at a uniform rate appropriate for the given job conditions so that satisfactory material consolidation and minimum rebound is achieved.


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3.4.1.6 Place shotcrete perpendicular to the receiving surface with the nozzle held at such a distance to produce maximum consolidation of the shotcrete and full encapsulation of the reinforcement. 3.4.1.7 Shoot dry-mixture shotcrete material within 45 min after batching or, in the case of prepackaged material, within 45 min after predampening. Shoot wet-mixture shotcrete material within the time limits in ASTM C94/94M. 3.4.1.8 Apply shotcrete using a circular or elliptical motion of the nozzle while building the required thickness. 3.4.1.9 Use sufcient material velocity, material consistency, and distance from the end of the nozzle to the receiving surface to produce maximum consolidation of the shotcrete and full encapsulation of the reinforcing steel. 3.4.1.10 In corners, direct the nozzle to bisect the corner angle. Apply shotcrete so sagging or sloughing does not occur. Where there is potential for accumulated rebound or overspray material to be incorporated into the Work at congested areas of steel reinforcement, embedded obstructions, corners, and recesses, use a compressed air blow pipe to remove loose material from the Work. 3.4.1.11 Discontinue placement of shotcrete or shield the nozzle stream if wind causes separation of ingredients in the nozzle stream. 3.4.1.12 Do not reuse rebound or overspray in the Work. 3.4.1.13 Remove laitance from shotcrete surfaces that are to receive additional shotcrete layers. 3.4.1.14 Surface preparation prior to the shooting of shotcrete shall comply with 3.1.5. 3.4.1.15 Do not apply shotcrete to surfaces with standing or owing water. 3.4.1.16 Remove hardened overspray and rebound from adjacent surfaces, including exposed reinforcement. 3.4.2 Intermediate surfaces 3.4.2.1 When applying more than one layer of shotcrete, use a cutting rod, brush with a stiff bristle, or other suitable equipment to remove all loose material, overspray, laitance, or other material that may compromise the bond of the subsequent layer of shotcrete. Conduct removal immediately after shotcrete reaches initial set. 3.4.2.2 Allow shotcrete to stiffen sufciently before applying subsequent layers. If shotcrete has hardened, clean the surface of all loose material, laitance, overspray, or other material that may compromise the bond of subsequent layers. Bring the surface to a saturated surface-dry condition at the time of application of the next layer of shotcrete. 3.4.3 Encasement of reinforcement 3.4.3.1 Place shotcrete to encase reinforcement and other embedments, and provide the cover required by Contract Documents. 3.4.3.2 Adjust air volume, material feed volume, and distance of the nozzle from the Work as necessary to encase reinforcement. 3.4.3.3 Keep the front face of the reinforcement clean during shooting operations so that shotcrete builds up from behind to encase the reinforcement without the formation of shadows or voids. ` , , ` ` ` , , , , ` ` ` ` ` ` , , ` , , ` , ` , , ` -


7

3.4.3.4 Shotcrete crew shall continuously remove accumulations of rebound and overspray using a compressed air blowpipe, or other suitable device, in advance of deposition of new shotcrete. ––Unless otherwise speci3.4.4 Hot weather shotcreting ed, do not place shotcrete when shotcrete temperature is above 95°F, unless prequalication testing in 1.5.1 shows that the required quality of materials can be achieved at higher temperatures. The temperature of reinforcement and receiving surfaces shall be below 90ºF prior to shotcrete placement. —Unless otherwise speci3.4.5 Cold weather shotcreting ed, shooting may proceed when ambient temperature is 40°F and rising. Stop shooting when ambient temperature is 40°F and falling, unless measures are taken to protect the shotcrete. Shotcrete material temperature, when shot, shall not be less than 50ºF. Do not place shotcrete against frozen surfaces. 3.4.6 Shotcrete temperature 3.4.6.1 Unless otherwise specied, when the average of the highest and lowest ambient temperature during the period from midnight to midnight is expected to drop below 40°F for more than 3 consecutive days, deliver shotcrete to meet the following temperatures in place immediately after placement: a) Between 55°F and 75°F for sections less than 12 in. in the least dimension; b) Between 50°F and 70°F for sections to 36 in. in the least dimension. 3.4.6.2 The minimum requirements of 3.4.6.1 may be terminated when ambient temperatures greater than 50°F occur during more than half of any 24-hour duration.

3.5—Finish 3.5.1 Gun nish —Leave nished shotcrete surface as gun nish unless otherwise specied. Proceed to rod, rubber oat, wood oat, or troweled nish. 3.5.2 Troweled or rod nish —Do not initiate cutting or nishing until the shotcrete is sufciently set to avoid sloughing or sagging. 3.6—Curing 3.6.1 When the daily mean temperature is above 40°F, curing shall be continuous for a minimum of 7 consecutive days or for the time necessary to attain 70 percent of the specied compressive or exural strength, whichever period is less. 3.6.2 If shotcrete is placed with daily mean temperatures 40°F or lower, cold weather protection shall be provided until the shotcrete achieves 70 percent of the specied strength. 3.6.3 Unless otherwise specied, complete moist curing by one of the following methods: a) Ponding or continuous sprinkling for a minimum of 7 days; b) Covering with an absorptive mat or sand that is kept continuously wet; c) Covering with impervious sheet material;


8


d) Use of curing compounds; apply twice the rate for formed surfaces as recommended by manufacturer if the surface is a gun nish. 3.6.4 Do not use natural curing in lieu of that specied in this section unless the relative humidity of the air in contact with the shotcrete remains at or above 85 percent and such curing is authorized by Architect/Engineer.

3.7—Protection 3.7.1 After placement 3.7.1.1 Unless otherwise specied, immediately after placement, protect shotcrete from premature drying or excessively hot or cold temperatures and mechanical injury. 3.7.1.2 Maintain shotcrete protection to prevent freezing of the shotcrete and to ensure the necessary strength development for structural safety. Remove protection in such a manner that the maximum decrease in temperature measured at the surface of the shotcrete in a 24-hour period shall not exceed the following: a) 50°F for sections less than 12 in. in the least dimension; b) 40°F for sections from 12 to 36 in. in the least dimension. 3.7.2 Protect surfaces not intended for shotcrete placement against deposit of rebound and overspray or impact from nozzle stream. 3.8—Tolerances 3.8.1 Dimensional tolerances of shotcrete shall comply with Contract Documents. 3.9—Repair of shotcrete 3.9.1 General 3.9.1 Repair defects in shotcrete in accordance with an approved procedure submitted in 1.4.1.15. 3.9.1.2 Remove voids, shadows, sagging, or other defects in the hardened shotcrete using light-duty chipping hammers (maximum 18 lb) followed by high-pressure water blasting or grit blasting to remove bruised shotcrete surface. 3.9.1.3 Conduct removal of defective shotcrete without the creation of feather edges. 3.9.1.4 In the repair of core hole surfaces and sawcut edges, roughen the core hole or cut surface and predampen prior to repair. 3.9.2 Shotcrete repair with commercial patching products —Repair shotcrete with commercial patching products, including: a) Portland cement mortar, modied with a latex bonding agent conforming to ASTM C1059/C1059M, Type II; b) Packaged, dry concrete repair materials conforming to ASTM C928/C928M. 3.9.3 Removal of stains, rust, eforescence, and surface deposits —Remove stains, rust, eforescence, and surface deposits considered objectionable by Architect/Engineer by methods acceptable to the Architect/Engineer. 3.10—Acceptance of Work 3.10.1 Remove and replace shotcrete that exhibits laminations, voids, or sand pockets exceeding the specied quality. Copyright American Concrete Institute Provided by IHS under license with ACI No reproduction or networking permitted without license from I HS

Remove and replace shotcrete that does not comply with the Contract Documents. 3.10.2 Shotcrete Work that meets specications shall be accepted. 3.10.3 Shotcrete Work that has previously failed to meet one or more requirements, but has been repaired to bring it into compliance shall be accepted. 3.10.4 Shotcrete Work that fails to meet one or more requirements and that cannot be brought into compliance shall be either accepted or rejected by Architect/Engineer. Modications to the mixture proportions or the shotcreting procedures shall be implemented to assure that remaining Work complies with the requirements. 3.10.5 The basis for acceptance or rejection of shotcrete properties shall be the specied compressive or exural strength. When additional criteria, properties, or both are required in the Contract Documents, acceptance criteria shall include compliance with those requirements. 3.10.6 Compliance with test properties 3.10.6.1 Compressive strength—Consider the compressive strength adequate if the average of the three cores from a test panel or from in-place shotcrete exceeds 85 percent of the specied compressive strength and no single core is less than 75 percent of the specied compressive strength. 3.10.6.2 Flexural strength —When required, the average exural strength of a set of three test beams from one panel shall equal or exceed the specied exural strength. 3.10.6.3 Boiled absorption and volume of permeable voids —When required, the average of tests on three specimens from a test panel, or from in-place shotcrete, shall be less than or equal to the specied boiled absorption and specied volume of permeable void limits at the specied test age with no single test greater than the specied boiled absorption plus 1 percent. 3.10.6.4 Flexural parameters —For FRS, and when required, exural parameters and toughness requirements shall comply with specied requirements in the Contract Documents. —When required, the average of the bond 3.10.6.5 Bond strength of the specied number of cores shall exceed the specied minimum strength with no single core bond strength less than 75 percent of the specied strength. (nonmandatory portion follows)

NOTES TO SPECIFIER General notes G1. ACI Specication 506.2 is to be used by reference or incorporation in its entirety in the Project Specication. Do not copy individual sections, parts, articles, or paragraphs into the Project Specication, because taking them out of context may change their meaning. G2. If Sections or Parts of ACI Specication 506.2 are copied into the Project Specication or any other document, do not refer to them as an ACI Specication because the specication has been altered. G3. A statement such as the following will serve to make ACI Specication 506.2 a part of the Project Specication:


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“Work on (Project Title) shall conform to all requirements of ACI 506.2 (Specication number with date sufx and title) published by the American Concrete Institute, Farmington Hills, Michigan, except as modied by these Contract Documents.” G4. Each technical Section of ACI Specication 506.2 is written in the three-part section format of the Construction Specications Institute, as adapted for ACI requirements. The language is imperative and terse. G5. ACI Specication 506.2 is written to the Contractor. When a provision of this specication requires action by the Contractor, the verb “shall” is used. If the Contractor is allowed to exercise an option when limited alternatives are available, the phrasing “either...or...” is used. Statements provided in the specication as information to the Contractor use the verbs “may” or “will.” Informational statements typically identify activities or options that, “will be taken” or “may be taken” by the Owner or Architect/Engineer.

FOREWORD TO CHECKLISTS F1. This foreword is included for explanatory purposes only; it is not a part of ACI Specication 506.2. F2. ACI Specication 506.2 may be referenced by the specier in the Project Specication for any building project, together with supplementary requirements for the specic project. Responsibilities for project participants must be dened in the Project Specication. ACI Specication 506.2

cannot and does not address responsibilities for any project participant other than the Contractor. F3. Checklists do not form a part of ACI Specication 506.2. Checklists assist the specier in selecting and speci fying project requirements in the Project Specication. F4. The Mandatory Requirements Checklist indicates Work requirements regarding specic qualities, procedures, materials, and performance criteria that are not dened in ACI Specication 506.2. The specier must include these requirements in the Project Specication. F5. The Optional Requirements Checklist identies specier choices and alternatives. The checklist identies the sections, parts, and articles of the ACI Reference Specication 506.2 and the action required or available to the specier. The specier should review each of the items in the checklist and make adjustments to the needs of a particular project by including those selected alternatives as mandatory requirements in the Project Specication. F6. The Submittals Checklist identies information or data to be provided by the Contractor before, during, or after construction. F7. Recommended references —Documents and publications that are referenced in the checklists of ACI Specica tion 506.2 are listed below. These references provide guidance to the Specier and are not considered to be part of ACI Specication 506.2.

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10


MANDATORY REQUIREMENTS CHECKLIST Section/Part/Article

1.1.1

Notes to Specier Specify whether shotcrete is structural or nonstructural. Specify if ber-reinforced shotcrete (FRS) or other specialty shotcrete is required.

1.4.1.9

Specify if ACI Nozzleman Certication is required for nonstructural shotcrete.

1.5.1

Specify if preconstruction testing is required.

1.6.3.1

Specify panel orientation to match Work if other than vertical.

2.1.7

Specify the grades, types, and sizes of reinforcement required.

2.4.1

Specify compressive strength required. For FRS, specify the exural strength and other exural p arameters.

2.4.2

2.4.4

2.4.5

Specify maximum w/cm based on project service conditions. Refer to ACI 318 or 350 to determine project requirements. Guidance with regard to freezing and thawing can be o btained from ASTM C33/C33M. Air entrainment may be required where the shotcrete is exposed to freeze/thaw, seawater, or deicing salts. Specify minimum air void parameters based on project service conditions. Refer to ACI 318 or 350 to determine project requirements. Guidance on the need for air entrainment to protect against freezing and thawing can be found in ASTM C33/C33M. Also specify the frequency of air testing. Specify maximum water-soluble chloride ion content based on project service conditions. Refer to ACI 318 or 350 to determine project requirements.

2.4.6

Specify limits, if any, on the types and dosages of supplementary cementing material.

2.4.7

If required, specify limits on the voids and absorption properties.

2.4.8

Specify if FRS is required and, if so, the exural strength and exural parameters required.

2.4.9

If required, specify bond strength of shotcrete to substrata.

2.5 3.4.3

Specify when mass or volume proportioning of the shotcrete is required. Shotcrete mixtures are normally propor tioned to achieve a specied compressive strength. Refer to ACI 506R if specic properties other than strength are required. Specify reinforcement cover requirements for shotcrete based on project service conditions. Refer to ACI 318 or 350 to determine project requirements.

3.4.5

Specify cold weather procedures. Refer to ACI 306R and 306.1.

3.8.1

Specify tolerances based on function and appearance. Shotcrete can be built to the same tolerance as cast-in-place concrete; however, for some structures such as tunnels, only cover thickness is required and tolerances are not specied unless project-specic requirements dictate. Sometimes shotcrete tolerances are increased by a factor of 2 from those in ACI 117. Refer to ACI 318 or 350 to determine project requirements.

OPTIONAL REQUIREMENTS CHECKLIST Section/Part/Article

1.4.1 1.4.1.7 1.4.1.13

Notes to Specier

Specify when there will be other submittal requirements. Some submittals may not be needed for some projects. Specify when aggregate absorption testing is required. The absorption values may be used to correct for absorbed moisture in the calculation of w/cm. Specify acceptance values for boiled absorption and volume of permeable voids. Typical values for quality shotcrete are a Maximum of 8 percent boiled absorption and 15 percent volume of permeable voids.

1.5.1.5

Specify when testing for other shotcrete properties will be required.

1.5.1.6 and 1.5.1.8

Specify when exural strength testing is required. Specify when a ratio of compressive to exural strength should be established so that during construction the more economical compressive strength testing might augment quality control requirements.

1.5.1.9

Specify acceptance criteria for degree of reinforcement encasement or severity of defects.

1.6.2.2

Specify when test specimens from other than test panels, such as from in-place shotcrete, are required.

1.6.2.4 and 2.4.4

Specify air content for wet-mixture shotcrete, if required.

1.6.3.1

Specify test panel orientation if o ther than vertical.

1.6.3.2 1.6.3.6

Specify when samples should be conditioned by a procedure other than soaking in accordance with ASTM C1604/ C1604M. When exural strength or toughness testing is required, specify where and how samples are to be taken. Refer to ACI 506R .

1.6.5 and 2.4.9

Specify when bond tests are required and specify where bond tests are to be conducted.

2.1.1

Specify when a specic type of cement is required to satisfy project requirements such as durability. Refer to ACI 318 or 350 to determine project requirements.



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11

2.1.2

Specify when supplementary cementitious materials are required or permitted to satisfy project requirements. Refer to ACI 318 or 350 to determine project requirements.

2.1.3

Specify when an alternative aggregate will be acceptable or is required.

2.1.4

2.1.5

Specify when nonpotable water will be acceptable, including any specic limitations. Refer to ACI 318 or 350 to determine project requirements. ASTM C1602/C1602M provides testing requirements for nonpotable water. Specify when ready-mixed wash water will be acceptable and include any limitations. Specify when admixtures are permitted or required, including type and grades. Refer to ACI 318 or 350 to determine project requirements. ASTM C1141 Type 1, Grade 3, and Type 2, Grade 3, are supplemental cementitious materials and are not admixtures. Shotcrete placement reduces entrained air content such that shotcrete with a 7 percent or higher air content prior to shooting will have an entrained air content of approximately 3 to 4 percent after placement. Wet-mixture shotcrete exposed to moderate or severe freezing-and-thawing conditions should have an entrained air content of at least 6 to 7 percent prior to shooting. Obtaining greater than 4 percent air in the in-place material is difcult. Specifying air entrainment for dry-mixture shotcrete is not common but has been satisfactorily used in severe freezing-and-thawing exposures. Specify limits and types of other acceptable admixtures. Specify maximum dosage if important. Calcium chloride accelerators are not recommended for reinforced shotcrete structures. Refer to tables in ACI 201.2R and 318 or 350 for limits. If specied, calcium chloride should conform to ASTM D98.

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2.1.6

Specify what types of bers are required. Refer to ACI 506.1R and ACI 506.5R

2.1.7

Specify when there are limitations on what reinforcement is required or permitted. Refer to ACI 318, 301, or 350 to determine project requirements.

2.1.8.1

Specify when sheet materials for curing are not permitted. Refer to ACI 318 or 350 to determine project requirements.

2.2

Specify when packaged preblended materials are permitted, including any limitations.

2.3

Specify when there are additional limitations and requirements for FRS.

2.4.3

Specify exural strength and other exural parameters when required on the project. Specify the limits. Refer to ACI 506.1R and ACI 506.5R .

2.4.4

If it is desired to conrm the air void parameters in hardened shotcrete, use the procedures in ASTM C457/C457M.

2.4.6 2.4.7

Specify limitations on suitability of supplementary cementitious materials, when they are permitted. Refer to ACI 318 or 350 to determine project requirements. Specify when shotcrete boiled absorption and volume of permeable voids testing will be required. Specify the requirements. Guidance can be found in ACI 506R .

2.4.9

Specify bond strength if required.

3.1.4.2

Specify when reduction of clearances between reinforcing bar laps may be permitted based on preconstruction testing.

3.1.5

Specify when air-supported forms may be used.

3.2.2

Specify when contraction joints are required. Also specify if reinforcement is to pass through the joint.

3.4.4

3.4.5

Specify when a shotcrete temperature limit that is higher or lower than 95°F for shotcrete members is required or acceptable based on the member being shot, location, relative humidity, and past experience. Review ACI 305R for guidance on specifying a higher or lower temperature. If shotcrete delivered in hot weather with a temperature higher than 95°F has been used successfully in given climates or situations, the higher temperature may be specied in place of the 95°F limit. Specify when revised temperature requirements may be acceptable. Requirements herein have been taken from ACI 306.1. For projects in cold climates, such as in northern winters, or in situations where it is prudent to require the Contractor to follow specic procedures to achieve the limits of 3.4.6, the temperature limits for cold weather may be deleted and ACI 306.1 can be referred to in its entirety. Options within ACI 306.1 must then be exercised.

3.4.6.1

Specify when other ambient temperatures are permitted.

3.5

Specify if a nish other than gu n nish is required.

3.6.3

Specify alternative curing systems if permitted.

3.7.1

Requirements for rate of temperature change have been excerpted from ACI 306.1. For optional cold-weather shotcreting requirements, specify ACI 306.1 in its entirety, if appropriate.

3.9

Specify what repair procedures are acceptable or required.

3.9.1

Edges of the repair area should not be feather-edged. Common methods used for edge preparation include sawcutting, chipping, grinding, sandblasting, hydro-milling, or other means to a depth of 1/2 to 1 in. normal to the surface of the member. Note: if saw-cutting or grinding is used, care should be taken to ensure reinforcing steel is not cut or damaged.



12


SUBMITTALS CHECKLIST Section/Part/Article

Notes to Specier

1.4.1.1

Mixture proportions for each mixture design and test reports for hardened and plastic properties for each mixture design.

1.4.1.2

Test reports of compressive strength and, when FRS is specied, exural strength and exural parameters.

1.4.1.3

w/cm for wet-mixture only.

1.4.1.4

Admixture data.

1.4.1.5

Cementitious materials data.

1.4.1.6

Aggregate data.

1.4.1.7

When required, aggregate absorption.

1.4.1.8

Qualications, certication, and experience of Work crew. Nozzlemen certication.

1.4.1.9

Submit proof of shotcreting experience.

1.4.1.10

Water source and data. Water report, when required.

1.4.1.11

When specied, ber material, length, and ber content.

1.4.1.12

Certicate showing compliance of reinforcement to specications.

1.4.1.13

When specied, shotcrete boiled absorption and volume of permeable voids test reports.

1.4.1.14

For hydration control admixtures, submit data.

1.4.1.15 and 3.9.1

When necessary, proposed repair procedures.

1.4.1.16

Data showing that curing materials comply with specications.

1.4.1.17

Contractor’s testing agency.

3.7.1

Method of measuring concrete surface temperature.

CHECKLIST REFERENCES ACI committee documents and documents published by other organizations are listed rst by document number and year of publication.

ACI 506R-05—Guide to Shotcrete ACI 506.1R-08—Guide to Fiber-Reinforced Shotcrete ACI 506.5R-09—Guide for Specifying Underground Shotcrete

American Concrete Institute (ACI) ACI 117-10—Specication for Tolerances for Concrete Construction and Materials and Commentary ACI 201.2R-08—Guide to Durable Concrete ACI 301-10—Specications for Structural Concrete ACI 305R-10—Guide to Hot Weather Concreting ACI 306R-10—Guide to Cold Weather Concreting ACI 306.1-90—Standard Specication for Cold Weather Concreting (Reapproved 2002) ACI 318-11—Building Code Requirements for Structural Concrete and Commentary ACI 350-06—Code Requirements for Environmental Engineering Concrete Structures

ASTM International ASTM C33/C33M-13—Standard Specication for Concrete Aggregates ASTM C1141/C1141M-08—Standard Specication for Admixtures for Shotcrete ASTM C1602/C1602M-12—Standard Specication for Mixing Water Used in the Production of Hydraulic Cement Concrete ASTM C1604/C1604M-05 (2012)—Standard Test Method for Obtaining and Testing Drilled Cores of Shotcrete ASTM D98-05—Standard Specication for Calcium Chloride

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As ACI begins its second century of advancing concrete knowledge, its original chartered purpose remains “to provide a comradeship in finding the best ways to do concrete work of all kinds and in spreading knowledge.” In keeping with this purpose, ACI supports the following activities: · Technical committees that produce consensus reports, guides, specifications, and codes. · Spring and fall conventions to facilitate the work of its committees. · Educational seminars that disseminate reliable information on concrete. · Certification programs for personnel employed within the concrete industry. · Student programs such as scholarships, internships, and competitions. · Sponsoring and co-sponsoring international conferences and symposia. · Formal coordination with several international concrete related societies. · Periodicals: the ACI Structural Journal and the ACI Materials Journal, and Concrete International. Benefits of membership include a subscription to Concrete International and to an ACI Journal. ACI members receive discounts of up to 40% on all ACI products and services, including documents, seminars and convention registration fees. As a member of ACI, you join thousands of practitioners and professionals worldwide who share a commitment to maintain the highest industry standards for concrete technology, construction, and practices. In addition, ACI chapters provide opportunities for interaction of professionals and practitioners at a local level.

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

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Specification for Shotcrete

The AMERICAN CONCRETE INSTITUTE was founded in 1904 as a nonprofit membership organization dedicated to public service and representing the user interest in the field of concrete. ACI gathers and distributes information on the improvement of design, construction and maintenance of concrete products and structures. The work of ACI is conducted by individual ACI members and through volunteer committees composed of both members and non-members. The committees, as well as ACI as a whole, operate under a consensus format, which assures all participants the right to have their views considered. Committee activities include the development of building codes and specifications; analysis of research and development results; presentation of construction and repair techniques; and education. Individuals interested in the activities of ACI are encouraged to become a member. There are no educational or employment requirements. ACI’s membership is composed of engineers, architects, scientists, contractors, educators, and representatives from a variety of companies and organizations. Members are encouraged to participate in committee activities that relate to their specific areas of interest. For more information, contact ACI.

www.concrete.org


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ACI 506.2-13 - Specification for Shotcrete.pdf

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