benefit ratios (TBR) [the adjusted traffic benefit ratio (TBRadj)] of
2.19 (2.16) and 2.24 (2.11) (Tables 4 and 5), respectively. Section 2,
with double reinforced layers, never reached the 25.4 mm rut
depth during the test and the rut depth of 12.7mmwas obtained at
3,167,943 ESALs. The performance of section 1 was much lower
than section 4, which indicates that the 203 mm thick Mexican
limestone is more effective than the 305 mm thick nonwoven
geotextile-wrapped sand embankment in reducing the pavement
rutting. Section 6 showed the lowest performance among the six
test sections mainly due to its much thinner base layer (254 mmvs.
457 mm).
The profiles of surface deformation were measured using eight
LVDTs, as shown in Fig. 2. Fig. 4 clearly demonstrates that the
reinforced sections exhibited a lower level of surface deformation
than the control section. The figure also shows that a small amount
of tilt occurred in the loading plate. This maybe due to variations in
the loading apparatus and/or local variations in the properties of
the HMA, base course, or subgrade (1).