UFC 3-260-03
15 Apr 01
f. Physical Properties of Concrete. Results of field and laboratory tests to determine the physical
properties such as slump, aggregate gradation, mix design, temperature, and curing of the concrete are
generally available in construction records.
g. Physical Properties of Bituminous Pavements. Results of field and laboratory tests to determine
the physical properties of bituminous pavements are generally available in construction records. Data
should include results of tests for Marshall stability, flow, percent bitumen by weight, density, voids rela-
tionships, aggregate gradation, specific gravity of bitumen and aggregate, and penetration (or viscosity)
and ductility of bitumen. If the pavement were designed accourding to Strategic Highway Research
Program (SHRP) criteria, the procedures and protocols governing the asphalt mixture design are available
in the American Association of State Highway Transportation Officials (AASHTO) specifications. The
results of test data should include: all asphalt binder testing to yield the SHRP performance grade (PG)
used in the construction project including techniques such as Brookfield viscosity, flash point, dynamic
shear rheometry, bending beam rheometry, and direct tension; all testing of modified asphalts that may
include elastic recovery, force ductility, and phase separation potential; all aggregate testing including
gradation, specific gravity, abrasion, soundness, crushed faces (fine and coarse aggregate fractions) thin,
elongated particles, and clay content; all testing of the asphalt-aggregate mixture including gyratory
compaction, specific gravity, water susceptibility, wheel tracking, and SHRP mixture analysis techniques.
All of the previously mentioned testing should be in strict accordance with AASHTO specifications where
appropriate.
h. Nondestructive Test Data. Nondestructive test (NDT) data required include deflection basins
(the applied force and surface deflections at offset distances from the load) obtained utilizing NDT
equipment and test procedures, and joint deflection data on rigid (and in some instances composite)
pavements.
i. Temperature Data. Temperature data are required for flexible pavements and pavements with a
flexible overlay at the surface to include 5-day mean air temperature for the 5 days prior to testing, surface
temperature at the time of testing, and average daily maximum and average daily mean air temperature
for each month.
3.
COLLECTION OF NDT DATA.
a. Equipment. The NDT procedure evaluates response of a pavement system to an applied load-
ing. An acceptable NDT device must provide an output containing a minimum of four deflections as
follows: the near one is measured at the center of the applied load, the far one is at a distance of at least
1.22 meters (48 inches) from the applied load, and the other two deflections are spaced equidistance in
between. Seven sensors are preferred. The number of layer moduli to be calculated from measured
deflections cannot exceed the number of sensors. The outermost sensor (farthest from the load) shall
be no less than 1.22 meters (48 inches) from the load, with the preferred minimum distance being
1.83 meters (72 inches). Of the remaining sensors, one should be located at the center of the loaded
area and the others at approximately 305-millimeter (1-foot) intervals from that point. The applied loading
must be measured and must be accurate to at least plus or minus 2 percent of the expected load.
Deflections must be determined at points on the pavement to describe a representative basin and must be
accurate to at least plus or minus 2 percent. Most deflection measurement devices have four or more
sensors to measure the deflection basin. Similarly, most deflection measurement devices have Sensor 1
at the center of load and the other sensors either at 305-millimeter (1-foot) intervals from that point or
adjustable to any spacing out to a distance of 1.83 meters (6 feet) or more. The NDT device recom-
mended for evaluation of military airfields is an impulse loading device commonly called a falling weight
deflectometer (FWD). The load on the pavement (impulse force) from an FWD is created by dropping
weights from different heights onto a rubber or spring buffer system. The standard loading plates used to
transmit the applied force to the pavement are either 305 millimeters (12 inches) or 457 millimeters
(18 inches) in diameter. The drop height can be varied to produce an impact force up to 224 kilonewtons
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