PaintSquare.com
Follow us on Twitter Follow us on LinkedIn Like us on Facebook Follow us on Instagram Visit the TPC Store
Search the site

 


D4787 Standard Practice for Continuity Verification of Liquid or Sheet Linings Applied to Concrete Substrates

All Standards | ASTM Standards
Search Standards


Click to Purchase and Download this Standard or Test Method

Revision Date: April 01, 2013
Updated On: June 04, 2013
Editorial Change:
 
5.1 The electrical conductivity of concrete is primarily influenced by the presence of moisture. Other factors, which affect the electrical continuity of concrete structures, include the following: 5.1.1 Presence of metal rebars, 5.1.2 Cement content and type, 5.1.3 Aggregate types, 5.1.4 Admixtures, 5.1.5 Porosity within the concrete, 5.1.6 Above or below grade elevation, 5.1.7 Indoor or outdoor location, 5.1.8 Temperature and humidity, and 5.1.9 Age of concrete.

5.2 The electrical conductivity of concrete itself may be successfully used for high-voltage continuity testing of linings applied directly with no specific conductive underlayment installed. However, the voltage required to find a discontinuity may vary greatly from point to point on the structure. This variance may reduce the test reliability.

5.3 Although the most common conductive underlayments are liquid primers applied by trowel, roller, or spray, and which contain carbon or graphite fillers, others may take the form of the following: 5.3.1 Sheet-applied graphite veils, 5.3.2 Conductive polymers, 5.3.3 Conductive graphite fibers, 5.3.4 Conductive metallic fibers, and 5.3.5 Conductive metallic screening.

5.4 Liquid-applied conductive underlayments may be desirable as they can serve to address imperfections in the concrete surface and provide a better base for which to apply the lining.

5.5 This practice is intended for use only with new linings applied to concrete substrates. Inspecting a lining previously exposed to an immersion condition could result in damaging the lining or produce an erroneous detection of discontinuities due to permeation or moisture absorption of the lining. Deposits may also be present on the surface causing telegraphing. The use of a high voltage tester on a previously exposed lining is not recommended because of possible spark through which will damage an otherwise sound lining. A low voltage tester can be used but could produce erroneous readings. 5.6 The user may consider this practice when performance requirements of the lining in a specified chemical environment require assurance of a lining free of discontinuities.

5.7 Factors affecting the dielectric properties and test voltage shall be considered. Some factors are the curing time of liquid-applied linings; the possible presence of electrically conductive fillers or solvents, or both; the possible presence of air inclusions or voids; and the compatibility of conductive underlayments with the specified lining. 5.8 A pulsed dc high voltage may cause a lining to breakdown at a lower voltage than would be the case for a continuous dc voltage.

(Back to all Standards)

 
   
Advertisements
 
KTA-Tator, Inc. - Corporate Office
 
New KTA Pipeline Inspection Kit
 
• Defelsko standard memory body
• Positector FTS 0-250 mils, cabled dry film thickness probe
• NEW Positector Shore D hardness probe
• All essential inspection equipment!
Visit www.ktagage.com
 

 
SAFE Systems, Inc.
 
Enduroguard -
The Tough Cable
for a Tough Industry.
 
Reduce maintenance costs and down time, increase job site safety with Enduroguard Cable. Available exclusively from SAFE Systems. UL listed, flexible, abrasion resistant and cut resistant.
 

 
SABRE Autonomous Solutions
 
Quality
 
The ALPHA1 provides a consistent finish day-in
day-out; job to job.
 

 
ARC / A.W. Chesterton Company
 
Rapid Curing Coating
 
Cures under adverse conditions with maximum adhesion
 

 
Carboline Company
 
Carboline launches new website!
 
The completely revamped website, offers quick and easy access to essential product information and is now mobile-friendly.
 

 
Novatek Corporation
 
Dustless Coatings Removal
 
Novatek Corporation, Dustless Coatings Removal Strip, clean and profile all dust free! Comply with new lead standards. Contact today: (866) 563-7800 www.Novatekco.com
 

 
Fischer Technology Inc.
 
TSA Coatings on Stainless Steel
 
Fischer’s Phascope PMP10 and ESD20TSA probe are incredibly accurate and easy to use.
 

 
 
 

Technology Publishing Co., 1501 Reedsdale Street, Suite 2008, Pittsburgh, PA 15233

TEL 1-412-431-8300  • FAX  1-412-431-5428  •  EMAIL webmaster@paintsquare.com


The Technology Publishing Network

Durability + Design PaintSquare the Journal of Protective Coatings & Linings Paint BidTracker

 
EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
MORE:      About PaintSquare.com   |   Privacy Policy (Updated 5/24/2018)   |   Terms & Conditions   |   Support   |   Site Map   |   Search   |   Contact Us