Active Standard ASTM D7228 | Developed by Subcommittee: E17.41
Book of Standards Volume: 04.03
Historical (view previous versions of standard)
Significance and Use
Analysis of deflection data from asphalt pavements almost always requires that the raw deflections or the analysis results from the load-deflection data be adjusted for the effects of pavement surface course temperature. Measuring the temperature at-depth normally requires that a hole be drilled into the pavement, partially filled with fluid, and the temperature measured with a hand-held device. Alternatively, thermistors or other temperature instrumentation may be permanently installed at various locations.
Current deflection testing equipment is often equipped with surface temperature sensing devices, for example an infrared thermometer that measures the surface temperature at every test location. To adequately adjust the deflection or deflection results for the effects of temperature, the temperature at some depth must be known.
This test method provides a means of estimating the temperature at-depth from the pavement surface temperature, the time of day, the previous day’s high and low air temperatures, and the desired depth where the temperature is to be estimated. Utilization of this method results in a significant savings in time over the conventional practice of manually drilling holes into the pavement, and it results in a significant increase in the volume of temperature data (one pavement temperature for each test point) and the ability to record temperature variations between test points.
1.1 This test method covers a means of predicting temperatures within the asphalt-bound layer(s) of a flexible pavement section.
1.2 Deflection testing commonly involves the measurement of pavement surface temperatures. This standard is based on temperature relationships developed as part of the Federal Highway Administration (FHWA) Long Term Pavement Performance (LTPP) Seasonal Monitoring Program.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D4602 Guide for Nondestructive Testing of Pavements Using Cyclic-Loading Dynamic Deflection Equipment
D4694 Test Method for Deflections with a Falling-Weight-Type Impulse Load Device
D4695 Guide for General Pavement Deflection Measurements
D5858 Guide for Calculating In Situ Equivalent Elastic Moduli of Pavement Materials Using Layered Elastic Theory
AASHTO StandardsT317-02 Standard Method of Test for Prediction of Asphalt-Bound Pavement Layer Temperatures
Federal Highway AdministrationLTPPGuidetoAsphaltTe Online Temperature Prediction and Correction Guide--TOC, November 2002
ICS Number Code 93.080.20 (Road construction materials)