United States Department of Transportation
i
Evaluation of MDOT's Distress Thresholds for Maintained Pavement Projects
-
2012-07-30
-
[PDF-1.12 MB]
Details:
-
Creators:
-
Corporate Creators:
-
Subject/TRT Terms:
-
Publication/ Report Number:
-
Resource Type:
-
Geographical Coverage:
-
Edition:Final project report.
-
Corporate Publisher:
-
Abstract:As an alternative to traditional contracting, pavement warranty has been adopted in Mississippi since 2000, aimed to
enhance pavement performance and protect the investment in pavement construction. Currently, a manual distress survey
method and the associated deduct point-based pavement condition rating approach are employed to monitor the
performance of warranty pavements (maintained projects). The main objective of this study is to evaluate the
appropriateness of using the current deduct points and distress thresholds to monitor the performance of the maintained
projects in Mississippi. In the study, a comprehensive literature review and online survey were conducted to review the
recent state of practice of pavement warranty in North America. The analytical section of the study employed pavement
distress and riding quality data collected from warranty pavements and the corresponding data of non-warranty pavements
stored in MDOT’s Pavement Management System (PMS) for the statistical analysis. Using raw data, converted deduct
points, and composite index as performance indicators, basic statistics were developed to investigate the distribution of
performance indicators at various service times and the corresponding percentiles associated with the existing threshold
values. In addition, pairwise comparisons were conducted to examine the evolvement of distress over time for warranted
and non-warranted pavements. Further, two sample t-tests were performed to compare the performance of warranted and
non-warranted pavements at the same service time. The survey study has shown that most other pavement warranty
programs in other states use direct measurements of pavement distresses or densities of pavement distresses for their
distress indicators and thresholds while the pavement warranty program at MDOT employs deduct points based distress
thresholds which are quantities converted from measurements of pavement distresses. The analytical results show that the
performance of the warranty pavements is significantly better than that of the non-warranty pavements at the same service
time level, and warranty pavements can maintain at high service levels for a longer time than non-warranty pavements.
The pavement warranty program adopted by MDOT has improved pavement performance, and is effective in practice.
However, the current distress thresholds adopted by MDOT are inconsistent with regard to the various corresponding
percentile levels for different distress types at a same service time, and the different increase rates of the percentile level
for different distress types over service time. It is suggested that direct measurements of pavement distresses or distress
densities be used as distress thresholds, and consistent threshold levels be implemented for all distress types.
-
Format:
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type:
