General testing requirements and procedures for analysis of

Dynaflect data for pavement evaluation studies are

1. Pavement and air temperature data. Air and pavement surface temper-

 atures can be obtained at suitable intervals during Dynaflect

 testing using handheld or pocket probe, thermister, thermocouple, or

 other temperature measuring devices. The mean pavement temperature

 can be determined by recording the temperature of oil poured into a

 3/8- or 1/2-inch diameter hole drilled with a masonry bit into the

 pavement within about a half-inch of the total thickness of the

 asphalt concrete. One location for a segment of roadway may be

 sufficient provided that solar radiation and wind effects are fairly

 uniform and do not vary enough to alter the average temperature more

 than 20F.

 It is recommended that conventional pavement response measure-

 ments (e.g., Dynaflect) be obtained when pavement temperatures are

 between 30F and 850F. High pavement temperatures may affect the

 deflection measurements and make it difficult to achieve reliable

 results. This is particularly true where binder viscosity and E

 are very low resulting in excessive volume changes near the loaded

 area and erroneous deflection measurements.

 2. Conduct Dynaflect tests at the desired interval (longitudinal dis-

 tance) with the sensors at .locations conforming to those shown in

 Figure F.1. Due to the potential for eccentric loading and varia-

 tions in pavement response for sensors 1 and 2, it is required that

 the average value be used in the analysis.