Technical information

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Offset in X from Loading Center Line [in.]
Surface Rutting [in.]
100 Passes 500 Passes
1000 Passes 5000 Passes
10000 Passes 20000 Passes
50000 Passes 60000 Passes
70000 Passes 90000 Passes
Figure 3.5.5: Rutting development in Section n1 at the central cross section during the
first 90,000 load passes (applied without wheel wander).
Figures 3.5.6 to 3.5.18 contain contour charts (13 charts in total) that show the
development of rutting in the APT. Each figure is basically a plan view of lane 1 with X
and Y axes as defined in Figure 3.5.1. The different colors (or shades) in the charts
represent different rutting depths (legend is identical in all figures). In preparing these
figures, use was made of all available profiles measured during the entire experiment;
each figure represents a different pass level, shown in a box on the lower right corner;
starting with pass #100 (Figure 3.5.6) and ending at pass #90,000 (Figure 17). The
outcome helps visualize how rutting progressed under load. One immediate observation
from these charts is that rutting was consistently deeper in the first half of the test lane
(i.e., Y<144 in.). This indicates structural heterogeneity that may, at least partially,
explain the dissimilarity in readings from gauge pairs that should, in theory, be
measuring identical response (see discussion in previous subsection).