Onsite Use of Recycled Asphalt Pavement Materials and Geocells to ...

3.6.8 Light Weight Deflectometer Test
Light Weight Deflectometer (LWD) tests, as shown in figure. 3.15, were carried out on
each pavement layer of the prepared test section including subgrade, base, and HMA surface.
ZFG 3000 LWD manufactured by Zorn Instruments, Germany, was used. This test is a
nondestructive method which measures the deflection of the plate under an impact load by a
falling weight. There is an acceleration sensor on the loading plate. When the falling weight
drops on the loading plate, the acceleration signal captured by the sensor can be used to calculate
the deflection of the plate and the dynamic deformation modulus (Evd) of the soil. The mass of
the falling weight was 10 kg and the falling distance was 73 cm The test has three different
loading plate diameters, of 15, 20, and 30 cm The large diameter loading plate is suitable for
fine grained soil while the small diameter plate is suitable for coarse grained soil or even HMA
surface.
3.7 Vibratory Plate Compactor
A vibratory plate compactor, as shown in figure 3.16, was used to compact the subgrade,
base, and HMA surface during the preparation of test sections. The vibratory plate compactor
was not used to compact the geocell-reinforced RAP base because it could not densify the infill
material well. Therefore, manual compaction using the modified Proctor compaction hammer
was performed for the infill material in the geocell-reinforced RAP base.
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