advance the State of the Practice in Pavement Management, practitioners still
acknowledge a gap between network level assessments and project level needs. Ironically, with today’s technology, network
level data is now collected at a density far greater than most originally
considered feasible (or cost effective) for project level evaluations. With current data acquisition and storage
speeds, technology is available to gather any essential data at highway speeds
(even structural capacity and safety data).
industry, we have been so well indoctrinated in the distinction between network
level and project level data that we may have lost sight of where the distinction
came from and/or the ultimate objective(s) for gathering such data. We find ourselves readily collecting data at
hundredths of a mile (or less) and then averaging the results to report network
level statistics. More importantly, we
find ourselves duplicating effort to try and reproduce project level
information for determining actual treatment needs. The practitioners (the individuals that
ultimately need to decide what needs to be done to which roads) struggle to use
network data to its full potential because of how it is being summarized and
now capable of collecting surface and structural performance data
simultaneously at highway speeds, it should now be feasible to better explore
how we close the gap between network level and project level evaluation. The emergence of these integrated devices have
created an opportunity, for the first time, for continuous and comprehensive evaluation
of a pavement network. There are of course still analytical challenges resulting
from the introduction of such technology. Recent national and international studies are
working to address these challenges. Additional research is needed to
facilitate adoption and proper application, in order to optimize both project
and network level pavement management agency needs.
A number of studies have investigated the
state-of-the-technology and use of highway speed continuous deflection devices
for network-level pavement structural evaluation.[i][ii][iii] Building upon these efforts, the Federal
Highway Administration (FHWA) research study entitled “Pavement Structural
Evaluation at the Network Level” evaluated two traffic speed devices, TSD and
RWD (rolling wheel deflectometer), that were identified as potential devices
currently on the market in the SHRP2-R06(F) effort. The raw measurements from these devices were
compared with those measured using sensors embedded in the pavement
surface. The study found that the
accuracy and precision of these devices are acceptable for network level
Recent studies show that current technology
is more efficient than traditional project level analyses. The focus is shifting from what network level
statistic to report to what data should be produced to facilitate the analyses
and ultimate designs.
[[i]]Strategic Highway Research Program (2012) “Assessment of Continuous
Pavement Deflection Measuring Technologies,” Final Report, Project
SHRP2–R06(F), Washington, DC.
[[ii]] Rada, G. R. and Nazarian, S. (2011) “The State-of-the-Technology of
Moving Pavement Deflection Testing,” Final Report, FHWA-DTFH61-08-D-00025, U.S.
Department of Transportation, Washington, DC.
[iii]] Jitin, A., Tandon V., and Nazarian S. (2006), “Continuous
Deflection Testing of Highways at Traffic Speeds,” Research Report No.
FHWA/TX-06/0-4380-1, Center for Transportation Infrastructure Systems, The
University of Texas at El Paso, El Paso, TX.
Katicha, S., Flintsch, G., Shrestha, S, Thyagarajan, S (2017) “Demonstration of
Network Level Structural Evaluation with Traffic Speed Deflectometer in
Virginia,” Project No. FHWA-DTFH61-11-D-00009-T-13008, U.S. Department of
Transportation, Washington, DC.
G.R., Nazarian, S., Visintine, B.A., Siddharthan, R and Thyagarajan, S (2016)
“Pavement Structural Evaluation at the Network Level; Final Report”, Research
Report No. FHWA-HRT-15-074,
U.S. Department of Transportation, Washington, DC