01089583

Component

Structural evaluation provides valuable information about the expected behavior of pavements and can be very useful at the network level of pavement management for project prioritization purposes. However, due to the expenses involved in data collection and analysis, structural capacity is usually not evaluated at the network level. In Kansas, due to limited resources and large size of the network (11,186 centerline miles; ~9000 miles of bituminous), annual network-level structural data collection at the same rate (5 to 10 tests with multiple drops per mile using a Falling Weight Deflectometer, FWD) as the project level is highly resource intensive. Rolling Wheel Deflectometer (RWD), which measures surface deflections at highway speed, is an alternate, faster method of pavement deflection testing for network-level data collection. This study was initiated to assess the feasibility of using RWD for network-level pavement deflection measurements in Kansas. RWD deflection data was collected under an 18,000-lb axle load and at a highway speed of about 55 mph on 207 miles of non-Interstate highways in northeast Kansas in July 2006. FWD data on these roads, collected from 1998 to 2006, were also used for comparing center deflections measured by RWD with those collected with an FWD. The computed effective structural numbers from the FWD and RWD deflection measurements were also compared. The FWD first sensor data was normalized to a load of 9,000 lbs and then corrected at a temperature of 68 degree F. The RWD deflection was also corrected for temperature. The results show that the deflections measured by RWD and the center (first sensor) deflections from FWD are statistically similar. The effective structural numbers computed from the FWD and RWD deflection measurements are also statistically similar. The temperature correction factors have significant influence on all these variables. An analysis of historical FWD data on the study sections showed that the average structural condition of the pavements of Kansas Department of Transportation (KDOT) non-Interstate network did not change significantly over the last five years. Thus, network-level deflection data can be collected at 5-year intervals on the KDOT highway network when there is no major structural improvement.

01084478

08-2648

English

20p

2008

Transportation Research Board 87th Annual Meeting

DVD

Figures; Photos; References (12) ; Tables (8)

Axle loads; Data collection; Deflection; Falling weight deflectometers; Pavement distress; Pavement management systems; Structural analysis

Rolling wheel deflectometers

Kansas

Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways

Transportation Research Board Annual Meeting 2008 Paper #08-2648

TRIS, TRB

Jan 29 2008 5:05PM