TECHNICAL
`GUIDELINES
`
`Prepared by the International Concrete Repair Institute
`
`October 2013
`
`Guideline No. 310.2R–2013
`
`Copyright ©2013 International Concrete Repair Institute
`
`Selecting and Specifying Concrete
`Surface Preparation for Sealers,
`Coatings, Polymer Overlays, and
`Concrete Repair
`
`Metromont Ex-1020, p.1
`
`

`

`TECHNICAL
`GUIDELINES
`
`Prepared by the International Concrete Repair Institute
`
`October 2013
`
`Selecting and
`Specifying Concrete
`Surface Preparation
`for Sealers, Coatings,
`Polymer Overlays, and
`Concrete Repair
`Guideline No. 310.2R-2013
`
`Copyright © 2013 International Concrete Repair Institute
`All rights reserved.
`International Concrete Repair Institute
`10600 West Higgins Road, Suite 607, Rosemont, IL 60018
`Phone: 847-827-0830 Fax: 847-827-0832
`E-mail: info@icri.org
`Web: www.icri.org
`
`Metromont Ex-1020, p.2
`
`

`

`About ICRI Guidelines
`The International Concrete Repair Institute (ICRI) was
`founded to improve the durability of concrete repair
`and enhance its value for structure owners. The iden-
`tification, development, and promotion of the most
`promising methods and materials are primary vehicles
`for accelerating advances in repair technology. Working
`through a variety of forums, ICRI members have the
`opportunity to address these issues and to directly
`contribute to improving the practice of concrete repair.
`
`A principal component of this effort is to make carefully
`selected information on important repair subjects
`readily accessible to decision makers. During the past
`several decades, much has been reported in the liter­
`ature on concrete repair methods and materials as they
`have been developed and refined. Nevertheless, it has
`been difficult to find critically reviewed information on
`the state of the art condensed into easy-to-use formats.
`
`To that end, ICRI guidelines are prepared by sanctioned
`task groups and approved by the ICRI Technical
`Activities Committee. Each guideline is designed to
`address a specific area of practice recognized as essen-
`tial to the achievement of durable repairs. All ICRI
`guideline documents are subject to continual review
`by the membership and may be revised as approved by
`the Technical Activities Committee.
`
`Technical Activities Committee
`Kevin A. Michols, Chair
`James E. McDonald, Secretary
`Frank Apicella
`Jorge Costa
`Andrew S. Fulkerson
`Fred Goodwin
`Gabriel A. Jimenez
`Ralph C. Jones
`Peter R. Kolf
`David Rodler
`Lee Sizemore
`Aamer Syed
`David Whitmore
`
`Producers of this Guideline
`ICRI Committee 310, Surface Preparation
`Andrew S. Fulkerson, Chair
`Patrick Winkler, Secretary*
`Randal M. Beard
`Don Caple
`Fred Goodwin
`David G. Karins
`Kenneth M. Lozen
`Kevin A. Michols
`Beth Newbold
`Jeffery Smith
`*Subcommittee Chair
`Synopsis
`Proper surface preparation is a key element in
`determining the success of a concrete restoration
`project. Improper surface preparation may lead
`to the failure of the protective system or repair
`material, resulting in further repairs, added
`expense, and loss of use, and may ultimately
`compromise the integrity of the structure.
`Surface preparation is the process by which a
`sound, clean, and suitably roughened surface is
`produced on a concrete substrate. Surface prepa-
`ration includes the removal of laitance, dirt, oil,
`films, paint, coatings, sound and unsound con-
`crete, and other materials that will interfere with
`the adhesion or penetration of a sealer, coating,
`polymer overlay, or repair material. Surface
`preparation will open the pore structure of the
`concrete substrate and establish profiles suitable
`for the application of the specified protective
`system or repair material.
`
`Keywords
`Abrasive blasting; acid etching; detergent scrub-
`bing; grinding; handheld concrete breakers;
`high- and ultra-high-pressure water jetting; low-
`pressure water cleaning; microcracking; needle
`scaling; rotomilling; scabbling; scarifying;
`shotblasting; surface preparation; surface profile;
`surface retarders.
`
`This document is intended as a voluntary guideline for the owner, design professional, and
`concrete repair contractor. It is not intended to relieve the professional engineer or designer
`of any responsibility for the specification of concrete repair methods, materials, or practices.
`While we believe the information contained herein represents the proper means to achieve
`quality results, the International Concrete Repair Institute must disclaim any liability or
`responsi bility to those who may choose to rely on all or any part of this guideline.
`
`310.2R-2013
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`Selecting and Specifying concrete Surface preparation for SealerS, coatingS, polymer overlayS, and concrete repair
`
`Metromont Ex-1020, p.3
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`

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`Contents
`
`Introduction ..................................................................................................................................... 1
`1.0
`1.1 Surface Preparation .................................................................................................................. 1
`
`1.2 Guideline Tools .......................................................................................................................... 1
`
`2.0 Definitions ....................................................................................................................................... 1
`3.0 Selecting Surface Preparation Method(s) ...................................................................................... 1
`3.1 Project Evaluation ..................................................................................................................... 1
`
`
`3.2 Evaluate Surface Preparation Method(s) .................................................................................... 2
`3.3 Select and Specify Surface Preparation Method(s) ..................................................................... 2
`
`
`3.4 Quality Control .......................................................................................................................... 2
`4.0 Mechanics of Concrete Removal .................................................................................................... 2
`
`4.1
`Introduction ............................................................................................................................... 2
`
`4.2 Cleaning.................................................................................................................................... 2
`4.3 Acid Etching and Surface Retarder ............................................................................................ 2
`
`
`4.4 Abrasion ................................................................................................................................... 3
`4.5 High-Pressure Water Erosion ..................................................................................................... 3
`
`
`4.6
`Impact ...................................................................................................................................... 3
`4.7 Pulverization ............................................................................................................................. 3
`
`5.0 Microcracking (Bruising) ................................................................................................................ 4
`5.1 Effect on Bond Strength ............................................................................................................ 4
`
`5.2 Risk of Introducing Microcracking ............................................................................................. 4
`
`6.0 Concrete Surface Profiles (CSPs) ................................................................................................... 5
`7.0 Method Selector .............................................................................................................................. 6
`7.1 CSP and Protective Systems ...................................................................................................... 6
`
`7.2 CSP and Preparation Methods ................................................................................................... 6
`
`8.0 Method Summaries ......................................................................................................................... 8
`
`8.1 Abrasive Blasting ...................................................................................................................... 8
`
`8.2 Acid Etching ............................................................................................................................ 10
`8.3 Handheld Concrete Breakers ................................................................................................... 12
`
`
`8.4 Detergent Scrubbing ............................................................................................................... 14
`
`8.5 Grinding .................................................................................................................................. 16
`8.6 High- and Ultra-High-Pressure Water Jetting ........................................................................... 18
`
`
`8.7 Low-Pressure Water Cleaning ................................................................................................. 20
`8.8 Rotomilling .............................................................................................................................. 22
`
`8.9 Needle Scaling ........................................................................................................................ 24
`
`
`8.10 Scabbling ................................................................................................................................ 26
`8.11 Scarifying ................................................................................................................................ 28
`
`
`8.12 Shotblasting ............................................................................................................................ 30
`
`8.13 Surface Retarders ................................................................................................................... 32
`9.0 References ..................................................................................................................................... 34
`
`9.1 Referenced Standards and Reports ......................................................................................... 34
`9.2 Cited References ..................................................................................................................... 34
`
`Appendix A: Surface Preparation Selection ............................................................................................... 35
`Appendix B: Testing ................................................................................................................................. 40
`Appendix C: Safety ................................................................................................................................... 48
`
`Selecting and Specifying concrete Surface preparation for SealerS, coatingS, polymer overlayS, and concrete repair
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`310.2R-2013
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`Metromont Ex-1020, p.4
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`310.2R-2013
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`Selecting and Specifying concrete Surface preparation for SealerS, coatingS, polymer overlayS, and concrete repair
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`Metromont Ex-1020, p.5
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`1.0 Introduction
`1.1 Surface Preparation
`This guide provides owners, designers, specifiers,
`contractors, and manufacturers with the tools
`needed to select and specify the methods for pre-
`paring concrete surfaces prior to the application of
`a protective system or repair material. Surface
`preparation is the process by which a sound, clean,
`and suitably roughened surface is produced on a
`concrete substrate. Surface preparation includes
`the removal of laitance, dirt, oil, films, paint, coat-
`ings, sound and unsound concrete, and other
`materials that will interfere with the adhesion or
`penetration of a sealer, coating, polymer overlay,
`or repair material. Proper surface preparation will
`open the pore structure of the concrete substrate
`and establish profiles suitable for the application
`of the specified protective system or repair material.
`Proper surface preparation is a key element in
`determining the success of a concrete restoration
`project. Improper surface preparation may lead to
`the failure of the protective system or repair mat-
`erial, resulting in further repairs, added expense,
`and loss of use, and may ultimately compromise
`the integrity of the structure. The existing conditions
`of the concrete and the type of protective system
`or repair material to be applied should be considered
`in determining the surface preparation method(s).
`The designer, specifier, contractor, and manufac-
`turer should all participate in the selection of the
`surface preparation method(s). Detailed attention
`to proper surface preparation will help ensure the
`long-term success of the restoration project.
`1.2 Guideline Tools
`The following tools are contained within the
`guideline to assist the user in the selection and/
`or specification of the proper surface preparation
`method(s):
`• Method Selector (Section 7.0): Identifies
`methods capable of producing the concrete
`surface profile(s) (CSP[s]) typically recom-
`mended for the protective system or repair
`material.
`• Method Summaries (Section 8.0): Discusses
`the capabilities, limitations, operating require-
`ments, and environmental factors for each
`method.
`• CSP Chips (Section 6.0): Provides replicas of
`surface preparation profiles produced by
`methods described in the guide and visual
`standards for specification, execution, and
`verification of surface profiles.
`
`• Method Selection Checklists (Appendix A):
`Provides checklists to help ensure that critical
`information is identified, organized, and con-
`sidered in the development of criteria for the
`selection of a surface preparation method(s).
`• Testing (Appendix B): Discusses various test
`methods that may be used to specify and
`evaluate the quality of the surface preparation.
`• Safety (Appendix C): Provides links to specific
`safety information.
`2.0 Definitions
`Definitions for terms used in this guideline may
`be found in ICRI Concrete Repair Terminology
`(http://www.icri.org/GENERAL/repairtermi-
`nology.aspx).
`3.0 Selecting Surface
`Preparation Method(s)
`3.1 Project Evaluation
`Concrete surface conditions, material require-
`ments, and job-site conditions will vary consider-
`ably for each project. Most projects will have
`unique conditions and requirements that must be
`evaluated to determine which surface preparation
`method(s) is/are suitable for the project and which
`will ensure the long-term success of the protective
`system and/or repair material. More than one
`method may be capable of producing the desired
`results. Appendix A provides a more complete list
`of items to be considered and can be used as a
`checklist in evaluating a project. The checklist will
`help ensure that the various conditions affecting
`the surface preparation have been considered.
`3.1.1 Substrate condition
`The condition of the substrate, including the pres-
`ence of unsound concrete, bond-inhibiting mate-
`rials, substrate deterioration, cracking, and surface
`contaminants, need to be evaluated to determine
`the nature and degree of preparation required. The
`surface preparation method must provide a clean,
`sound substrate with a surface profile appropriate
`for the specific material installation.
`3.1.2 Material requirements
`Surface preparation requirements may vary with
`the material selected. The manufacturer of the
`system may have specific requirements for sur-
`face preparation, including the surface profile and
`moisture sensitivity, and should be consulted.
`Proper surface preparation could impact the
`
`310.2R-2013 - 1
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`manufacturer’s warranty. The properties and appli-
`cation requirements of the selected protective
`system or repair material must be determined prior
`to the selection of a surface preparation method.
`3.1.3 Job-site requirements
`Noise, vibration, dust, and water may be generated
`by various preparation methods. The need for
`uninterrupted use of the structure, concerns about
`the operating environment, or the potential for
`property damage may limit the choices. Mechanical
`ventilation, available power sources, the size of
`door openings, and minimum clearance may also
`affect surface preparation decisions. The surface
`preparation may also release hazardous contami-
`nants (for example, asbestos from old flooring
`mastic). Any condition that may affect the method
`of surface preparation should be considered.
`3.2 Evaluate Surface
`Preparation Method(s)
`Selecting the method(s) that will provide a clean,
`sound substrate and optimize the success of the
`material installation requires knowledge of the
`available options. The surface profile achieved
`following the surface preparation is often the
`primary requirement in specifying the preparation
`method(s). The method selector chart may be
`used to make a preliminary identification of the
`methods capable of producing the required CSP.
`Each of the methods capable of meeting the
`CSP requirement can be compared in the method
`summaries section, which provides data on the
`capabilities, limitations, operating requirements,
`and environmental considerations for each sur-
`face preparation method.
`3.3 Select and Specify Surface
`Preparation Method(s)
`The final selection is based on the relationship
`between substrate conditions, material require-
`ments, and job-site conditions. The specification
`may include a CSP range as well as other criteria,
`such as bond strength. These requirements should
`be clearly defined in the specification, along with
`the test method(s) that will be used to evaluate
`the completed surface preparation. The test pro-
`cedures described in Appendix B may be used in
`preparing the specifications to ensure that the
`desired results are achieved.
`3.4 Quality Control
`The CSP chips (CSP 1-10) provide benchmark
`profiles to aid in achieving the desired result. The
`
`prepared surface should be compared to the CSP
`chips specified for the project. Tests, such as the
`tensile bond test, may be performed to verify that
`all deteriorated or damaged concrete has been
`removed. Other specified tests should be per-
`formed prior to installing the protective system
`or repair material. The cost of providing addi-
`tional surface preparation will be significantly
`less than the cost of correcting a failure of the
`installed system or repair. Appendix B describes
`various tests that may be used to evaluate the
`prepared concrete surface. SSPC-SP 13/NACE
`No. 6, ASTM D5295, ASTM E1857, and ASTM
`F2471 provide additional considerations for sur-
`face preparation and quality control.
`4.0 Mechanics of
`Concrete Removal
`4.1 Introduction
`In addition to project-specific requirements, the
`selection of a surface preparation method should
`ensure that:
`• The surface is not damaged;
`• The reinforcing steel is not damaged, nor its
`bond with the concrete compromised; and
`• Vibration, impact, or construction loads do not
`weaken the concrete.
`This section describes the mechanics used by
`the various surface preparation methods to
`remove deteriorated concrete and contaminates
`from the surface. This information will help users
`determine the potential of each preparation
`method to achieve the desired results and also
`assess the potential for damage to the substrate
`that may be caused by the individual methods.
`4.2 Cleaning
`Cleaning does not noticeably alter the profile of
`concrete surfaces. Cleaning and detergent scrub-
`bing are accomplished through one or a com-
`bi nation of the following: the surfactant effect
`of det er gents, the solvent effect of water, the
`shearing force of brushes, and the force of low-
`velocity water. Applicable methods: low-pressure
`water cleaning and detergent scrubbing.
`4.3 Acid Etching and
`Surface Retarder
`Acid etching chemically dissolves calcium
`hydroxide and calcium silicate, which make up
`the hydrated solids in cement paste. The dissolu-
`tion of these materials at the surface causes a
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`slight loss of cement paste and produces a very
`light profile on the exposed surface. Surface
`retarders slow the hydration of cement, allowing
`low-pressure water cleaning to remove the
`retarded layer, creating an exposed aggre gate
`surface. Applicable methods: acid etching and
`surface retarders.
`4.4 Abrasion
`Abrasive force applied through grinding with
`stones, abrasive discs, or blocks with embedded
`diamonds wears away the cement paste, fines,
`and coarse aggregate at a uniform rate to pro-
`duce a nearly flat surface having little or no pro-
`file (Fig. 4.1). Applicable methods: grinding.
`4.5 High-Pressure Water Erosion
`Erosion causes the flushing away or progressive
`disintegration of concrete surfaces. A stream of
`water projected onto the surface under high pres-
`sure will result in the gradual erosion of the sur-
`face. The impact of the water and the water
`velocity combine to wear away the cement paste.
`As exposure to water jetting increases, so will the
`profile as the softer paste and embedded fines
`erode, leaving behind “islands” of the harder
`coarse aggregate. Under prolonged exposure to
`water jetting, the coarse aggregate will be undercut
`and washed away (Fig. 4.2). Applicable methods:
`high- and ultra-high-pressure water jetting.
`4.6 Impact
`Several preparation methods strike the surface
`repeatedly with hardened points to produce
`momentary mechanical loads that exceed the
`strength of the concrete, causing it to fracture.
`The force of the impact pulverizes and fractures
`the cement paste and aggregate at and adjacent
`to the point of contact (Fig. 4.3 and 4.4). Some
`of the cracks and loosened aggregate may remain,
`leaving a “bruised” layer at the surface. Appli-
`cable methods: scarifying, scabbling, rotomilling,
`needle scaling, and handheld concrete breakers.
`4.7 Pulverization
`The cutting effect is derived from the collision of
`small particles traveling at a high velocity against
`the concrete surface (Fig. 4.5). Because the mass
`of the particles is comparatively small, their
`impact is not known to produce bruising. Hard,
`sharp-edged media and high pressure can produce
`fast cutting rates. As with water jetting, the
`cement paste is usually reduced at a faster rate
`than the coarse aggregate. This difference in
`removal rate has the effect of exposing and under-
`
`cutting the coarse aggregate to produce a surface
`that will become highly profiled as exposure time
`is increased. Applicable methods: steel shot-
`blasting and abrasive blasting.
`
`Fig. 4.1: Grinding
`
`Fig. 4.2: High- and ultra-high-pressure water jetting
`
`Fig. 4.3: Scarifying, scabbling, rotomilling,
`needle scaling
`
`Fig. 4.4: Handheld concrete breaker
`
`Fig. 4.5: Abrasive blasting, shotblasting
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`5.0 Microcracking
`(Bruising)
`5.1 Effect on Bond Strength
`
`Fig. 5.1.a: Microcracking of the concrete
`
`Fig. 5.1.b: Microcracking
`
`weakened plane (Fig. 5.1a to 5.1c). It is generally
`accepted that the extent of the damage increases
`with the weight and power of the equipment used.
`However, the use of sharp, fine-toothed cutters
`contacting the surface at a shallow angle may
`reduce or prevent the development of bruising.
`The relative risk of introducing bruising or micro-
`cracking into the substrate is indicated for each
`method in Section 5.2. Surfaces prepared using
`impact methods should be tested using a tensile
`pulloff test to confirm that the prepared surface
`does not contain microcracks that may compro-
`mise the installation of a repair material or protec-
`tive system (refer to Appendix B).
`5.2 Risk of Introducing
`Microcracking
`Figure 5.2 identifies the potential risk of intro-
`ducing microcracking when performing surface
`preparation using the method listed.
`Surface preparation using methods resulting
`in a high probability of microcracking, including
`handheld concrete breakers, rotomilling, and scab-
`bling, generally require further surface preparation
`to remove the microcracks. Surface preparation
`using methods resulting in a moderate probability
`of microcracks, including needle scaling and scar-
`ifiers, may require further surface preparation, and
`the surface should be evaluated to determine if
`the preparation created microcracks. All surfaces
`should be tested, regardless of preparation method,
`to ensure adequate concrete strength and a properly
`prepared surface (refer to Appendix B).
`
`Fig. 5.1.c: Microcracking under LMC overlay
`
`Several of the preparation methods described may
`locally damage the prepared substrate. Field
`studies have shown that bond strengths of surfaces
`prepared using high-impact mech anical methods
`are frequently lower compared to surfaces pre-
`pared using nonimpact methods. This reduction
`in bond strength is caused by the fracturing of the
`cement paste and loosening of the aggregate
`without fully separating from the surface. This
`creates a weakened or “bruised” surface layer of
`interconnecting microcracks typically extending
`to a depth of 1/8 to 3/8 in. (3 to 10 mm). Micro-
`scopic exam ination usually indicates that cracks
`initiate at the surface at approximately a 45-degree
`angle and propagate horizontally to produce a
`
`Abrasive blasting
`Acid etching
`Handheld concrete breakers
`Detergent scrubbing
`Grinding
`High- and ultra-high-pressure water jetting
`Low-pressure water cleaning
`Rotomilling
`Needle scaling
`Scabbling
`Scarifying
`Shotblasting
`Surface retarders
`
`Fig. 5.2: Potential risk of microcracking during
`surface preparation
`
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`6.0 Concrete Surface
`Profiles (CSPs)
`Several of the methods summarized are capable
`of producing a range of profiles on concrete
`surfaces. Communication of project objectives
`and requirements may be improved by using
`CSPs to define the desired surface profile (ampli-
`tude or roughness).
`ICRI has identified 10 distinct profiles pro-
`duced by the surface preparation methods
`described in this guideline. As a set, these profiles
`replicate degrees of roughness considered to be
`suitable for the application of one or more of the
`sealer, coating, polymer overlay systems, and/or
`concrete repair materials. Each profile carries a
`CSP number ranging from CSP 1 (nearly flat)
`through CSP 10 (very rough; amplitude greater
`than 1/4 in. [6 mm]). The profile characteristics
`for each preparation method are identified by
`CSP number in the “Profile” section of the
`method summaries. Molded replicas* of these
`
`profiles provide clear visual standards for pur-
`poses of specification, execution, and verifica-
`tion. These benchmark profiles may be referenced
`in specifications, material data sheets, applica-
`tion guidelines, and contract documents to
`effectively communicate the required surface
`profile. It is probable that more than one profile
`will produce acceptable results, and a range of
`suitable profiles should be specified.
`The concrete surfaces shown in Fig. 6.1 to
`6.10 were produced using a variety of prepara-
`tion methods. Although each numbered CSP
`replica bears the characteristic pattern and tex-
`ture of the specific preparation method used, each
`replica is representative of the profile height
`(amplitude) obtained with all methods identified
`with the same CSP number.
`
`*Molded replicas are available with this guideline by
`contacting ICRI at the number listed on the back cover
`of this document or on ICRI’s website at http://www.
`icri.org/bookstore/bkstr.asp.
`
`Caution! The texture and
`appearance of the profile
`obtained will vary depending
`on the concrete strength, the
`size and type of aggregate,
`and the finish of the concrete
`surface. On sound substrates,
`the range of variation can
`be sufficiently controlled to
`resemble the referenced CSP
`standard. As the depth of
`removal increases, the profile
`of the prepared substrate will
`be increasingly dominated by
`the type and size of the
`coarse aggregate.
`
`Fig. 6.1: CSP 1
`(acid-etched)
`
`Fig. 6.2: CSP 2
`(grinding)
`
`Fig. 6.3: CSP 3
`(light shotblast)
`
`Fig. 6.4: CSP 4
`(light scarification)
`
`Fig. 6.5: CSP 5
`(medium shotblast)
`
`Fig. 6.6: CSP 6
`(medium scarification)
`
`Fig. 6.7: CSP 7
`(heavy abrasive blast)
`
`Fig. 6.8: CSP 8
`(scabbled)
`
`Fig. 6.9: CSP 9
`(heavy scarification—
`rotomilled)
`
`Fig. 6.10: CSP 10
`(handheld concrete
`breaker followed by
`abrasive blasting)
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`Figures 6.11 and 6.12 provide a guide to the
`general appearance of a CSP 10. After prepar-
`ation is complete, the aggregate should appear
`clean and crisp and protrude above the paste line
`a minimum of 1/4 in. (6 mm).
`
`Fig. 6.11: CSP 10—Surface prepared
`using handheld concrete breaker followed
`by abrasive blasting
`
`Fig. 6.12: CSP 10—Surface prepared using
`high-pressure water jetting
`
`7.0 Method Selector
`7.1 CSP and Protective Systems
`The type of protective system or repair material
`to be applied will impact the type of surface
`preparation selected. Penetrating sealers will
`have little or no effect on the appearance of the
`prepared surface. Any surface defects, contami-
`nants, or profile resulting from the surface
`preparation will be visible. Thin films may be
`formulated to achieve high hiding power; how-
`ever, even relatively minor surface imperfections
`and profiles produced by surface preparation
`equipment will be visible. High-build materials
`will have both high hiding power and some
`ability to fill irregularities and level the prepared
`surfaces. A smooth finish over higher profiles
`may be achieved by increasing the thickness of
`the applied coating system. Manufacturers of
`these materials often have minimum thickness
`requirements, which can be affected by the sur-
`face profile. A surface profile greater than
`specified by the manufacturer may result in an
`increase in the cost of the system. Overlays and
`repair materials are generally installed such that
`the depth of the material covers the amplitude of
`the surface profile.
`Possible surface profiles to be used with
`various protective systems are given in Table 7.1.
`Consult the manufacturer to determine the rec-
`ommended surface profile.
`7.2 CSP and
`Preparation Methods
`An approximate range of surface profiles
`ob tained using various preparation methods is
`shown in Table 7.2.
`
`6 - 310.2R-2013
`
`Selecting and Specifying concrete Surface preparation for SealerS, coatingS, polymer overlayS, and concrete repair
`
`Metromont Ex-1020, p.11
`
`

`

`Table 7.1: Protective Systems
`
`Concrete Surface Profile
`
`Material to be applied
`
`CSP 1
`
`CSP 2
`
`CSP 3
`
`CSP 4
`
`CSP 5
`
`CSP 6
`
`CSP 7
`
`CSP 8
`
`CSP 9 CSP 10
`
`Sealers,
`0 to 3 mils (0 to 0.075 mm)
`
`
`
`Thin films,
`4 to 10 mils (0.01 to 0.025 mm)
`
`High-build coatings,
`10 to 40 mils (0.025 to 1.0 mm)
`
`Self-leveling toppings,
`50 mils to 1/8 in. (1.2 to 3 mm)
`
`Polymer overlays,
`1/8 to 1/4 in. (3 to 6 mm)
`
`Concrete overlays and repair materials,
`>1/4 in. (>6 mm)
`
`Table 7.2: Preparation Methods
`
`Surface preparation method
`
`CSP 1
`
`CSP 2
`
`CSP 3
`
`CSP 4
`
`CSP 5
`
`CSP 6
`
`CSP 7
`
`CSP 8
`
`CSP 9 CSP 10
`
`Concrete Surface Profile
`
`Detergent scrubbing
`
`Low-pressure water cleaning
`
`Grinding
`
`Acid etching
`
`Needle scaling
`
`Abrasive blasting
`
`Shotblasting
`
`High- and ultra-high-pressure water jetting
`
`Scarifying
`
`Surface retarder (1)
`
`Rotomilling
`
`Scabbling
`
`Handheld concrete breaker
`
`(1) Only suitable for freshly placed cementitious materials
`
`310.2R-2013 - 7
`
`Selecting and Specifying concrete Surface preparation for SealerS, coatingS, polymer overlayS, and concrete repair
`
`Metromont Ex-1020, p.12
`
`

`

`8.0 Method Summaries
`8.1 Abrasive Blasting
`
`Fig. 8.1.a: Column
`
`Fig. 8.1.c: Reinforcement cleaning
`
`Fig. 8.1.b: Floor
`
`Fig. 8.1.d: Protective equipment
`
`8.1.1 Summary
`Abrasive blasting is used to clean and profile concrete
`surfaces (Fig. 8.1.a). The process can provide a light,
`clean profile, often referred to as a “brush blast,” or it
`can be used to achieve a moderate profile. It may also
`be used to re