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Federal Highway Administration > Publications > Public Roads > Vol. 71 · No. 2 > 508 Caption

Sept/Oct 2007
Vol. 71 · No. 2

Publication Number: FHWA-HRT-07-006

508 Caption

Bar chart. Adhesion Strength of Overcoat Systems Before and After Laboratory Testing. The bar chart shows the adhesion strength of the overcoat systems before and after the 4,000-hour laboratory tests. The small "b" after each entry in the legend stands for "before," while the small "a" beside every second entry indicates "after." As shown, the adhesion strength values of all the overcoat systems remained about the same after the testing. The x axis is labeled "Surface For Overcoat" and consists of three groupings of 12 bars, with the first grouping (at left) labeled "Lead dash Alkyd," then "I O Z slash Vinyl," and "S S P C dash S P 3." The 12 bars per grouping represent before and after values for six overcoats: Alkyd, M C U 2, M C U 3, H B Acrylic, C S A, and Epoxy. The y axis is labeled "Adhesion Strength, P S I" and ranges from 0 to 1,800 in 200 p s i increments. The data read as follows (from left to right): For Lead dash Alkyd substrate, Alkyd overcoat before 1,144, after 1,161; M C U 2 before 1,206, after 1,243; M C U 3 before 1,131, after 1,257; H B Acrylic before 690, after 678; C S A before 344, after 432; Epoxy before 1,213, after 1,236. For I O Z slash Vinyl substrate, there were no data for Alkyd before and after; M C U 2 before 1,050, after 998; M C U 3 before 812, after 807; H B Acrylic before 466, after 474; C S A before 344, after 342; Epoxy before 955, after 1,061. And for S S P C dash S P 3 substrate, Alkyd overcoat before 1,314, after 1,277; M C U 2 before 1,403, after 1,410; M C U 3 before 1,555, after 1,455; H B Acrylic before 411, after 542; C S A before 352, after 396; Epoxy before 1,504, after 1,298.

Graph plot. Rust Creepage at the Scribe on Alkyd Surfaces. This plot shows observed creepage of six coating materials applied over alkyd surfaces. The y axis indicates accumulative rust creepage at the scribe on a scale of 0 to 7 millimeters. The x axis indicates test time in hours on a scale of 0 to 4,000 hours. Creepage for each of the materials progressed approximately linearly, except that there was no observed creepage for calcium sulfonate, or C S A, between 2,000 and 4,000 hours. Rust creepage at the scribe on H B acrylic measured from about 1 millimeter at 2,000 hours to about 5.8 millimeters at 4,000 hours. Rust creepage at the scribe with alkyd measured from about 0.5 millimeter at 1,000 hours to about 4.8 millimeters at 4,000 hours. Rust creepage at the scribe with M C U 3 measured from about 1 millimeter at 1,500 hours to about 4.2 millimeters at 4,000 hours. Rust creepage at the scribe with epoxy measured from about 0.4 millimeter at 1,500 hours to about 3.7 millimeters at 4,000 hours. Rust creepage at the scribe with M C U 2 measured from about 0.5 millimeter at 1,500 hours to about 3.2 millimeters at 4,000 hours.

The formula for plotting H B Acrylic is: lowercase y equals 1.2314 times lowercase x, that amount minus 5.1371, where R squared (the linear regression coefficient) equals 0.9971. The formula derived for creepage with alkyd is: lowercase y equals 0.7614 times lowercase x, that amount minus 1.7314, where R squared equals 0.9868. The formula derived for creepage with M C U 3 is: lowercase y equals 0.6716 times lowercase x, that amount minus 1.6041, where R squared equals 0.9976. The formula derived for creepage with epoxy is: lowercase y equals 0.7027 times lowercase x, that amount minus 2.0568, where R squared equals 0.9345. The formula derived for creepage with M C U 2 is: lowercase y equals 0.6392 times lowercase x, that amount minus 2.123, where R squared equals 0.9372.

Bar chart. Rust Creepage at the Scribe Versus Substrate, Laboratory. The bar chart shows the extent of rust creepage at the scribe developed on the three different substrates using overcoats of various materials. The x axis is labeled "Substrate" and has three groupings of substrates (from left to right): "Aged Lead dash Alkyd," "Aged I O Z slash Vinyl," and "S S P C dash S P 3." The y axis is labeled "Rust Creepage at the Scribe, mm" and ranges from 0 to 7 millimeters in 1-millimeter increments. The legend reads from top to bottom: Alkyd, M C U 2, M C U 3, H B Acrylic, C S A, and Epoxy. From the left, as plotted on the bar chart, the Aged Lead dash Alkyd grouping reads as follows: Alkyd, 4.9; M C U 2, 3.4; M C U 3, 4.4; H B Acrylic, 5.9; C S A, 0.4; and Epoxy, 3.9. For the Aged I O Z slash Vinyl: Alkyd, (no data); M C U 2, 3.6; M C U 3, 4.2; H B Acrylic, 2.3; C S A, 1.1; and Epoxy, 1.7. For the S S P C dash S P 3: Alkyd, 3.8; M C U 2, 5.2; M C U 3, 4.8; H B Acrylic, 6.5; C S A, 0; and Epoxy, 5.0.

Bar chart. Rust Creepage at the Scribe Versus Substrate, Outdoors. The bar chart shows the extent of rust creepage at the scribe developed on the three different substrates with various overcoat materials when the panels were exposed to real-world conditions outdoors in New Jersey. The x axis is labeled "Substrate" and has three groupings of substrates (from left to right): "Aged Lead dash Alkyd," "Aged I O Z slash Vinyl," and "S S P C dash S P 3." The y axis is labeled "Rust Creepage at the Scribe, mm" and ranges from 0 to 18 millimeters in 2-millimeter increments. The legend reads from top to bottom: Alkyd, M C U 2, M C U 3, H B Acrylic, C S A, and Epoxy. From the left, as plotted on the bar chart, the Aged Lead dash Alkyd grouping reads as follows: Alkyd, 5.0; M C U 2, 6.7; M C U 3, 6.1; H B Acrylic, 4.6; C S A, 4.8; and Epoxy, 5.0. For the Aged I O Z slash Vinyl: Alkyd, no data; M C U 2, no data; M C U 3, no data; H B Acrylic, no data; C S A, no data; and Epoxy, no data. For the S S P C dash S P 3: Alkyd, 4.3; M C U 2, 3.0; M C U 3, 4.8; H B Acrylic, 5.0; C S A, 0; and Epoxy, 16.9.

This data flowchart, titled "TransNet Dashboard Data Flow," contains a central circle labeled "TransNet Dashboard" with arrows leading to 10 circles labeled, clockwise, "Public" (in color), "SANDAG Board," "MTS," "NCTD," "Caltrans Staff," "SANDAG Staff," "Other Agencies," "Cities/County," "Contractors/Consultants," and "ITOC." Arrows lead up to the central circle from boxes below it labeled "Budget/Expenditures," "Scheduling," and "Scope/Risk/Cost Estimates."s Within the Budget/Expenditures box are seven circles connected by arrows pointing up from the bottom. The circles are labeled (starting from the top): "Actual Dollars Expended," "'Middleware' Financial Data," and (two sets of circles leading to that circle), on the right, "SANDAG Financials (IFAS)" and "SANDAG Financial Information; Actual," and, on the left, "Caltrans Financials (FIDO/TRAMS)" and "Caltrans Financial Information; Actual Time Charges." On the far left is a circle labeled "Program Funding and Budgeting" and connected from the left to the "Middleware" Financial Data circle. Inside the Scheduling box are four circles connected by arrows pointing up from the bottom. The circles are labeled (starting from the top): "Earned Percent Complete," "Earning Rules Established," "Resource Loaded Schedules," and "Logic Based Schedules." The Scope/Risk/Cost Estimates box has four circles connected by arrows pointing up from the bottom. The circles are labeled (starting from the top): "Cost Management System," "Corridor Directors Trends, Risks, Issues, Progress Input," and "Project Manager Trends Risks, Issues, Progress Input." The fourth circle, labeled "Project Cost Estimates; Project Changes," is on the right side with an arrow pointing to the top circle. The following legend is included:

Caltrans—California Department of Transportation

FIDO—Financial Data in Oracle

IFAS—Integrated Financial and Accounting System

ITOC—Independent Taxpayer Oversight Committee

MTS—Metropolitan Transit System

NCTD—North County Transit District

SANDAG—San Diego Association of Governments

TRAMS—Transportation Accounting and Management System

Bar graph. Gloss Retention by Overcoat Material on Three Substrates. The bar graph summarizes the gloss retention of various overcoat materials for three substrates (Lead dash Alkyd, I O Z slash Vinyl, and S S P C dash S P 3) after a 4,000-hour laboratory test. The researchers measured the gloss of M C U 2, M C U 3, and epoxy using incident light coming at 60-degree angle and measured the gloss of H B acrylic and C S A with incident light coming at 20-degree angle. The x axis is labeled "Overcoat Material" and shows three bars for each type of the six overcoat materials. The bars are labeled in the legend as Lead dash Alkyd, I O Z slash Vinyl, and S S P C dash S P 3. The overcoat materials on the x axis (from left to right) are Alkyd, M C U 2, M C U 3, H B Acrylic, C S A, and Epoxy. The y axis is labeled "Gloss Retention, Percent" and ranges from 0 to 90 percent in 10-percent increments. The data read as follows (from the left): For Alkyd, the gloss retention for Lead dash Alkyd was 59.1 percent, no specimen was available for the I O Z slash Vinyl material, and gloss retention for S S P C dash S P 3 was 58 percent. For M C U 2, Lead dash Alkyd retained 43.9 percent of its gloss, I O Z slash Vinyl retained 41.8 percent of its gloss, and S S P C dash S P 3 retained 44.6 percent gloss. For M C U 3, Lead dash Alkyd, 55.6 percent; I O Z slash Vinyl, 49.5 percent; and S S P C dash S P 3, 39.3 percent. For H B Acrylic, Lead dash Alkyd, 69.0 percent; I O Z slash Vinyl, 79.3 percent; and S S P C dash S P 3, 77.9 percent. For C S A, Lead dash Alkyd, 73.5 percent; I O Z slash Vinyl, 68.4 percent; and S S P C dash S P 3, 75.8 percent. For Epoxy, Lead dash Alkyd, 16.5 percent; I O Z slash Vinyl, 18.7 percent; and S S P C dash S P 3, 14.7 percent.

Graph plot. Rust Creepage at the Scribe on I O Z slash Vinyl Surfaces. This plot shows observed creepage applied over aged I O Z slash Vinyl surfaces. The y axis indicates accumulative rust creepage at the scribe on a scale of 0 to 4.5 millimeters. The x axis indicates test time in hours on a scale of 0 to 4,500 hours. Creepage for each of the materials progressed approximately linearly, except that there is only one plotted point for C S A. Rust creepage at the scribe on M C U 3 measured from about 0.4 millimeter at 1,500 hours to about 4.25 millimeters at 4,000 hours. Rust creepage at the scribe with M C U 2 measured from about 1.5 millimeters at 2,000 hours to about 3.75 millimeters at 4,000 hours. Rust creepage at the scribe with H B acrylic measured from about 0.8 millimeter at 3,000 hours to about 2.4 millimeters at 4,000 hours. Rust creepage at the scribe with epoxy measured from about 0.5 millimeter at 3,000 hours to about 1.8 millimeters at 4,000 hours. Rust creepage at the scribe with C S A has just one plotted point, about 1.1 millimeters at 4,000 hours.

The formula derived for M C U 3 is: lowercase y equals 0.0015 times lowercase x, that amount minus 1.7811, where R squared equals 0.9886. The formula derived for creepage with M C U 2 is: lowercase y equals 0.0013 times lowercase x, that amount minus 1.273, where R squared equals 0.9322. The formula derived for creepage with H B acrylic is: lowercase y equals 0.0014 times lowercase x, that amount minus 3.3, where R squared equals 1. The formula derived for creepage with epoxy is: lowercase y equals 0.0013 times lowercase x, that amount minus 3.4, where R squared equals 1.

Graph plot. Rust Creepage at the Scribe on S S P C dash S P 3 Surfaces. This plot shows observed creepage of five coating materials applied over S S P C dash S P 3 steel surfaces. The y axis indicates accumulative rust creepage at the scribe on a scale of 0 to 7 millimeters. The x axis indicates test time in hours on a scale of 0 to 4,500 hours. Creepage for each of the materials progressed approximately linearly, except that there was no observed creepage for C S A between 2,500 and 4,000 hours. Rust creepage at the scribe on H B acrylic measured from about 0.8 millimeter at 500 hours to about 6.5 millimeters at 4,000 hours. Rust creepage at the scribe with M C U 2 measured from about 0.7 millimeter at 500 hours to about 5.2 millimeters at 4,000 hours. Rust creepage at the scribe with epoxy measured from about 0.9 millimeter at 1,000 hours to about 5.0 millimeters at 4,000 hours. Rust creepage at the scribe with M C U 3 measured from about 1.8 millimeters at 1,500 hours to about 4.8 millimeters at 4,000 hours. Rust creepage at the scribe with alkyd measured from about 1.3 millimeters at 1,500 hours to about 3.8 millimeters at 4,000 hours. There was no observed creepage for C S A between 2,500 and 4,000 hours.

The formula derived for creepage with H B acrylic is: lowercase y equals 0.0017 times lowercase x, where R squared equals 0.986. The formula derived for creepage with M C U 2 is: lowercase y equals 0.0013 times lowercase x, that amount minus 0.1746, where R squared equals 0.9777. The formula derived for creepage with epoxy is: lowercase y equals 0.0014 times lowercase x, that amount minus 0.59, where R squared equals 0.9904. The formula derived for creepage with M C U 3 is: lowercase y equals 0.0012 times lowercase x, that amount minus 0.1275, where R squared equals 0.9889. The formula derived for creepage with alkyd is: lowercase y equals 0.001 times lowercase x, where R squared equals 0.9887.

Graph plot. Rust Creepage at the Scribe Versus Exposure Time. This plot shows observed creepage developed by six coating materials after 24-month outdoor exposure. The y axis indicates accumulative rust creepage at the scribe on a scale of 0 to 8 millimeters. The x axis indicates exposure time in months on a scale of 0 to 30. Creepage for each of the materials progressed approximately linearly. Rust creepage at the scribe on M C U 2 measured from about 4.0 millimeters at 12 months to about 6.75 millimeters at 24 months. Rust creepage at the scribe with M C U 3 measured from about 3.5 millimeters at 12 months to about 6.1 millimeters at 24 months. Rust creepage at the scribe with epoxy measured from about 2.6 millimeters at 12 months to about 5.0 millimeters at 24 months. Rust creepage at the scribe with alkyd measured from about 2.5 millimeters at 12 months to about 4.75 millimeters at 24 months. Rust creepage at the scribe with C S A measured from about 2.5 millimeters at 12 months to about 4.6 millimeters at 24 months. Rust creepage at the scribe with H B acrylic measured from about 1.1 millimeters at 6 months to about 4.6 millimeters at 24 months. There was no observed creepage for C S A between 2,500 and 4,000 hours.
The formula derived for creepage with M C U 2 is: lowercase y equals 0.2983 times lowercase x, where R squared equals 0.8667. The formula derived for creepage with M C U 3 is: lowercase y equals 0.258 times lowercase x, where R squared equals 0.9441. The formula derived for creepage with epoxy is: lowercase y equals 0.2201 times lowercase x, where R squared equals 0.9289. The formula derived for creepage with alkyd is: lowercase y equals 0.2139 times lowercase x, where R squared equals 0.9893. The formula derived for creepage with C S A is: lowercase y equals 0.2132 times x, where R squared equals 0.7252. The formula derived for creepage with H B acrylic is: lowercase y equals 0.1845 times lowercase x, where R squared equals 0.8839.

Graph plot. Rust Creepage at the Scribe Over S S P C dash S P 3 Steel Surfaces Versus Exposure Time. This plot shows observed creepage developed by six coating materials after 24-month outdoor exposure. The y axis indicates accumulative rust creepage at the scribe on a scale of 0 to 18 millimeters. The x axis indicates exposure time in months on a scale of 0 to 30. Creepage for each of the materials progressed approximately linearly, except that there was no observed creepage for C S A between 18 and 24 months. Rust creepage at the scribe on epoxy measured from about 3.0 millimeters at 6 months to about 17.0 millimeters at 24 months. Rust creepage at the scribe with H B acrylic measured from about 1.0 millimeter at 6 months to about 5.0 millimeters at 24 months. Rust creepage at the scribe with M C U 3 measured from about 1.0 millimeter at 6 months to about 5.0 millimeters at 24 months. Rust creepage at the scribe with alkyd measured from about 1.5 millimeters at 6 months to about 4.3 millimeters at 24 months. Rust creepage at the scribe with M C U 2 measured from about 0.3 millimeters at 6 months to about 3.0 millimeters at 24 months.

The formula derived for creepage with epoxy is: lowercase y equals 0.7633 times lowercase x, that amount minus 2.15, where R squared equals 0.983. The formula derived for creepage with H B acrylic is: lowercase y equals 0.2183 times lowercase x, that amount minus 0.3, where R squared equals 0.9568. The formula derived for creepage with M C U 3 is: lowercase y equals 0.1956 times lowercase x, where R squared equals 0.9822. The formula derived for creepage with alkyd is: lowercase y equals 0.1833 times lowercase x, where R squared equals 0.9669. The formula derived for creepage with M C U 2 is: lowercase y equals 0.145 times x, that amount minus 0.5, where R squared equals 0.9888.

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