Comparison of Surface Resistivity to Bulk Diffusion Testing of Concrete

1
Comparison of Surface Resistivity to Bulk
Diffusion Testing of Concrete

• Christopher C. Ferraro Ph.D.
• Assistant In Engineering
• Department of Civil and Coastal Engineering,
  University of Florida
• Mario Paredes P.E.
• State Corrosion Engineer
• Florida Department Transportation

2
Research Significance
Corrosion induced deterioration is the most
common cause of bridge degradation in Florida
3
FDOT Chloride Penetration Research Program

• Started In 2002, Consisted of 3 phases
• 1st Phase (2002-2003) Characterization of
  structural concrete placed in the field using
• AASHTO T277/ASTM C1202 Chloride Penetration
  Test
• Surface Resistivity (Florida Method FM5-578)
• 2nd Phase(2003-2007) Find the best electrical
  indicators of permeability correlated to
  diffusion
• Bulk Diffusion (NT Build 443)
• RMT (NT Build 492)
• AASHTO T277/ASTM C1202 Chloride Penetration
  Test
• Surface Resistivity (Florida Method FM5-578)
• 3rd Phase (2007-2009) Surface Resistivity as a
  nondestructive test to evaluate field structures

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The Chloride Ion Penetration Test
Cut and Epoxy 26th Curing Day
Desiccate 27th Curing Day
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The Chloride Ion Penetration Test
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Chloride Ion Penetration Test AASHTO-T277/ASTM
C1202
Negatively charged ions move from the anode
reservoir to the cathode reservoir.
Stanish, K.D. et al
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Chloride Ion Penetration Test Limitations

• Temperature
• Ionic Contribution
• Hydroxyl ion formation
• Conductive Materials
• Effort Required for Specimen Preparation
• Cost

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Diffusion Test Bulk Diffusion (NT Build 443)
Cylinder is sliced at 364 days of exposure for
Chloride analysis
16.5 NaCl
Each slice is ¼ in thick
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Bulk Diffusion Test NordTest NTBuild 443
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Electrical Indicators of Ion Penetration
FM5-522 Impress Current
NT Build 443 - RMT
Stanish, K.D. et al
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Surface Resistivity FM 5-578
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Surface Resistivity Testing
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Surface Resistivity
Broomfield, J. et al
Applied Current
Measured Voltage
Chloride Ion Penetration Test Limitations
Chloride Ion Penetration Test Limitations
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Advantages of the Surface Resistivity Test

• Temperature
• Ionic Contribution
• Hydroxyl ion formation
• Effort Required for Specimen Preparation
• Cost
• Conductive Materials Still a problem

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Comparison of Resistivity and Chloride Ion
Penetration
Chini, A. et al
529 Data Sets
Surface Resistivity (kW-cm)
Coulomb Values
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Precision of Methods

• Single-Operator Precision for penetration testing
• Single Operator Coefficient of Variation
• Surface Resistivity 8.2
• Chloride Penetration Test 12.3

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91 Day SR Correlation to 1 3 year BD
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Research Program cont.

• The third phase of research
• Surface resistivity as a NDT test to evaluate
  field structures
• Surface Resistivity as a Performance Test for
  Transport Properties Presuel-Moreno et.al
  (yesterdays sesson)

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Geometry Effects

• ?real ? ?measure
• Curvature of sample forces equi-potential
  lines into smaller areas.
• The result is a modified resistivity reading.
• The real resitivity of concrete can be calculated
  by
• ?real ?measure/K
• Where K is a correction factor that accounts for
  the geometrical effects of the test (Morris, W.
  et al.)

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Geometry Effects
Morris, W. et al
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Geometry Effects
Drying Time
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Geometry Effects
Distance From Top
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Geometry Effects
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Geometry Effects
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References
Florida Method of Test for Concrete Resistivity
as an Electrical Indicator of Its Permeability,
(FM5-578) Florida Department of Transportation,
2004 Standard Method of Test for Resistance of
Concrete to Chloride Ion Penetration, (T259-80),
American Association of State Highway and
Transportation Officials, Washington, D.C.,
U.S.A., 1980 Standard Method of Test for
Electrical Indication of Concretes Ability to
Resist Chloride, (T277-93), American Association
of State Highway and Transportation Officials,
Washington, D.C., U.S.A., 1983 Standard Test
Method for Electrical Indication of Chlorides
Ability to Resist Chloride (ASTM C1202-94) 1994
Annual Book of ASTM Standards V 04.02, ASTM,
Philadelphia, pg. 620-5 Berke, N. S., and Hicks,
M.C., Estimating the Life Cycle of Reinforced
Concrete Decks and Marine Piles Using Laboratory
Diffusion and Corrosion Data, Corrosion Forms
and Control for Infrastructure, ASTM STP 1137, V.
Chaker, ed., American Society for Testing and
Materials, Philadelphia, 1992 Broomfield, J.,
and Millard, S., Measuring Concrete Resistivity
to Assess Corrosion Rates, Concrete Report from
the Concrete Society/Institute of Corrosion
Liaison Committee, pp. 37-39 Chini, A.,
Muszynski, L., Hicks, J., Determination of
Acceptance Permeability Characteristics of
Performance-Related Specifications for Portland
Cement Concrete, Florida Department of
Transportation, July 11, 2003 Hooton, R.,
Thomas, M., Stanish, K., Prediction of Chloride
Penetration in Concrete, Federal Highway
Administration, October 2001 Morris, W., Moreno,
E.I. and Sagues, A. A., Practical Evaluation of
Resistivity of Concrete in Test Cylinders using a
Wenner Array Probe, Cement and Concrete
Research, Vol. 26, No. 12, pp. 1779-1787, 1996
Powers, R., Sagues, A., Cerlanek, W., Kasper,
C., Li, L., Liang, H., Poor, N., Baskaran, R.,
Corrosion Inhibitors in Concrete Interim
Report, Federal Highway Administration,
FHWA-RD-02-002, March 2002 Stanish, K., Hooton,
R., Thomas, M., Testing the Chloride Penetration
Resistance of Concrete A Literature Review,
FHWA Contract DTFH61-97-R-00022Prediction of
Chloride Penetration in Concrete Streicher,
P.E. and Alexander, M.G., A Chloride Conduction
Test for Concrete, Cement and Concrete Research,
Vol. 25, No. 6, pp. 1284-1294, 1995