Potential Projects are identified by two key factors – Pavement Condition and Ride
quality. These two performance measures are the foundation of MassDOT’s Pavement
Management Project Selection Process.
PSI-Worst of roughness, rutting, distresses
Access to accurate and objective condition data is critical to the selection of cost
effective projects. MassDOT uses equipment specifically designed for this purposes.
The information obtained during the annual pavement condition inventory is listed on
this slide.
2
At the end of a testing season, we have a complete condition assessment of the
pavement condition of all DOT roadways and most of the Commonwealth’s NHS
Routes.
This map displays condition of all DOT roadways in categories of excellent (blue), good
(green), fair (yellow) and poor (red). While this is enough to select projects using a
worst-first approach, it does not provide a systematic approach to the cost effective
prioritization or management of the statewide pavement structure.
3
Projects are selected using a comprehensive multi-year analysis using Deighton DTIMS.
This customized software used to develop multi-year programs that are optimized
based on annual spending. The following sequence outlines the potential treatment
and performance modeling process.
MassDOT began implementing Pavement Preservation when feasible since 2002.
5
This is a matrix of the pavement rehabilitation options for a pavement section. Based
on the specific pavement conditions (cracking , rutting & ride), the functional class of
the roadway and the underlying pavement type, there is an appropriate
preservation/rehabilitation treatment.
MassDOT developed these matrices to help identify appropriate treatments for
the different pavement distress. The matrices helped identify and set overlaps
between different treatments for the same condition ranges to provide for
alternative strategies for the benefit cost optimization and helped to identify gaps
in condition ranges where no treatment would be triggered.
The matrices were used to build the treatment triggers which ultimately help to
provide a list of alternative strategies for a given roadway segment (project) and
any subsequent treatments to be applied later.
6
Each pavement distress has a performance model that considers the roadway
classification. These model are used to forecast the pavement condition in future
years, schedule work based on anticipated conditions, and evaluate the financial
impact of deferring work.
7
Each of the 5000+ pavement sections is analyzed based on its current and its predicted
future conditions. The PMS uses the treatment selection matrix to quantify the
benefits of applying the proscribed treatment during the analysis years. Once a multiyear budget has been input, this iterative process analyzes any of sections which meet
the “work required” threshold and the calculated the incremental benefit cost of
applying each treatment during the proscribed analysis year.
8
Incremental Benefit Cost (IBC) is used to determine the “ideal timing” and “ideal
treatment” under the given funding requirements. The area under the curve of
pavement condition models is used in this analysis. Traffic Volumes and Traffic Factors
(k) are used to help in this selection process.
9
10
11
A Pavement Management System is a tool that helps Engineers make educated
decisions. It does not make decisions without additional feedback. Difficult decisions
must be made when the statewide needs significantly exceed the dollars available.
When projects are initiated prior to design and 3-4 years before construction, project
values are based on historical costs for similar pavement rehabilitation treatments.
Some scope increases are unforseeable, the ability to maintain the statewide
conditions becomes challenging when directives increase the scope of the projects
without the associated funding. Budget for this program was cut approximately 25%
last year and is projected to increase by 1-2% over the next few years. We use a 4%
inflation factor. Basically, we are going backwards.
12