Transportation Research Program Overview

Statewide Planning & Research Program (SP&R)

WINTERPORT GEOSYNTHETICS An experimental construction project was constructed in 1997 along Rt.1A in Winterport-Frankfort. The test sections include different applications of structural and drainage geosynthetics to improve the performance of a roadway reconstructed over poor soils. The roadway section consists of the standard thick 24” gravel subbase and 6” pavement. Instrumentation and data collection was installed to determine stresses and responses to loads, freeze-thaw, etc. Analysis to date shows stresses and strains on the structural geosynthetics to be a small percentage of maximum allowances. The drainage geocomposites are showing excellent results in effectively removing ground water. This study has allowed us to monitor the performance of the geosynthetic applications.

PERMEABILITY OF BASE MATERIALS The Department has and will be constructing pavement structures using drainable base layers. Numerous test sections will be constructed and monitored for performance, maintainability, and cost effectiveness. This study will conduct lab and field permeability tests on the drainage layers and provide recommendations on the most economical materials.

SAFETY OF TRAFFIC SIGNALS. Crash analysis shows that safety at signalized intersections has been declining. Studies by the Insurance Institute for Highway Safety show that an increasing number of drivers running red lights may be the primary cause of this safety deterioration. This study will use field observations, conflict studies, crash data analysis, and in-depth interviews with people involved with crashes in order to identify crash reduction countermeasures at signalized intersections.

RELATING PAVEMENT THICKNESS TO PERFORMANCE The Department's Pavement Preservation Program amounts to approximately 91 million dollars and 400 miles of resurfacing in the upcoming BTIP. Hot mix asphalt resurfacing thicknesses are presently based on engineering judgment and experience. There is a need to better identify the added life that thicker pavement overlays will provide. This study will test four different HMA overlay thicknesses using scaled, accelerated load testing equipment. The number of traffic loads applied and pavement distress criteria will be used to determine the service life of typical pavement overlays.

IDENTIFICATION OF COMMUNICATION NEEDS This study will project the Department's future communication needs and provide recommendations on the most cost effective means to meet those needs. The focus will be on electronic communications between the central office, Division offices, and M&O camps. There will also be attention given to our current and projected Intelligent Transportation Systems needs including Road Weather Information Stations, Weigh in Motion systems, and Commercial Vehicle automated clearance systems and traveler information systems.

WATERSHED DRAINAGE Based on a 1981 U.S. Water Resources Council study current methods to predict peak flows for small drainage watersheds are grossly inaccurate. When current methods were compared to actual gauged (true) flows errors ranging from 55% to 75% for underestimation and 105% to 310% overestimation were determined. Clearly this could lead to under- and over- sizing culverts. The costs associated with materials are significant. However, the cost associated with flood event damage can be enormous. This study will gage 15 diverse watersheds geographically spread across the state. Peak flow data will be compared to current prediction methods and results analyzed. This three-year study will provide an indication of the accuracy of the models.

RECOMMENDATION AND VALIDATION OF SCOUR FORMULAE FOR MAINE RIVERS - PHASE III: DATA ACQUISITION & ANALYSIS The primary objective of the research is to determine formulae which best describe the sediment transport characteristics of Maine rivers. The first phase of the research involved a review of all published scour formulae. By identifying those formulae, which were derived for conditions similar to our local ones, it would be possible to isolate a subset of equations, which could be used in subsequent scour evaluations. The second phase of the project is a more systematic plan to obtain data and overcome the difficulty created by insufficient data. Information will be acquired regarding flood velocities, stages, and scour depths at 3 sites on a regular basis for a period of 6 months. This information would provide a way to validate the recommended formulae. The third phase of the project is a more comprehensive data collection effort involving a USGS mobile unit, which will collect field data during flood events. This data will be used in the national database and Maine 's own database to analyze scour equations. This will be a four (4) year data collection effort depending upon the flood events that occur.

INTEGRAL ABUTMENTS ON SHALLOW LEDGE Whenever appropriate the Department uses integral abutment bridge types due to their cost effectiveness versus conventional abutment types. Integral abutments eliminate the need for costly and maintenance-intensive open expansion joints. Also, expensive cofferdam construction and work in the water is minimized. Current design practices limit integral abutment usage to subsurface conditions with greater than ten feet to ledge. Design of these abutments on shallow ledge could provide a more economical bridge structure. It is anticipated that up to six structures per BTIP could be designed in this manner if research is successful. This study will develop laboratory models such that integral abutments and proper details could be evaluated for shallow ledge conditions. If modeling is successful than a second phase will instrument and evaluate an integral abutment constructed on shallow ledge.

SAFE WAYS TO SCHOOL The percentage of children who walk or bike to school has declined drastically in the last thirty years from over 80% in the 1960's to less than 20% today. Accompanying this decline has been a dramatic increase in obesity in adults and children alike. Physical inactivity has contributed to the 100% increase in childhood obesity in the U.S. since 1980. This study will conduct an in-depth analysis of three selected school districts in Maine . Current practices will be measured, attitudinal surveys administered, obstacles to walking and biking identified, and implementation plans to overcome these obstacles developed.

RWIS / ANTI-ICING Snow and ice control improvements has been identified as one of the Departments goals in its Strategic Plan. RWIS / Anti-icing technology involves the timely application of chemicals and is being successfully demonstrated throughout the country. The Department should evaluate this technology for quantitative evidence of its effectiveness. The objective of this study is to evaluate RWIS/Anti-icing technology in Maine . A Road Weather Information System has been designed and installed to be used by crews to assess the need and timing of anti-icing chemicals in the proper amounts and at the right time. Department crews have gained hands-on experience with this technology.

TIDAL RESTRICTION STUDY The Army Corp of Engineer's Coastal America Program provides planning assistance to states for the identification and assessment of degraded tidal wetland sites. The focus of this study will be on sites where the wetland degradation is caused primarily by tidal flow restrictions associated with roadways. The study area to be investigated is the coastal area from the northern boundary of the Scarborough marsh watershed to the Sheepscot River . The benefits of this study will be the identification of tidal restrictions in the study area and the options/opportunities for repairing any degraded adjacent wetlands. The Study information will provide to the Department a list of mitigation sites available for future MDEP and ACOE compensatory use in this region of the state.

DEVELOP AASHTO PAVEMENT DESIGN GUIDELINES FOR ROADWAYS WITH TIRE SHRED EMBANKMENT The Department and the University of Maine have worked closely over the past ten years in defining engineering properties of tire shreds and monitoring performance of various highway applications. This has resulted in millions of scrap tires being removed from stockpiles and reused in a beneficial way in our transportation infrastructure. This study will develop design methodology that can be used by highway and pavement designers where tire shreds are part of the highway embankment. The end result will be an AASHTO accepted design.

ANALYSIS OF HIGH SPEED FERRY ALTERNATIVES The Maine Sensible Transportation Policy Act requires MaineDOT to evaluate a full range of reasonable transportation alternatives. Relieving congestion along the Maine coast is an identified need. Use of ferryboats is a reasonable alternative. This study will analyze the potential of using high-speed ferries along the Maine coast. This will include site visits and interviews with manufacturers, potential routes, oceanographic condition assessment, engineering evaluations, and selection of high speed ferries meeting Maine needs. Phase 1 of this study has been completed. This portion of the study identifies the most suitable high-speed craft for the Maine coastline. Phase 2, funded in this program, will provide us with general information concerning the environmental impact of fast ferries in various operating conditions and methods to reduce wake wash problems.

HYDROLOGY STUDY Presently land use factors are not considered in the existing methodology for the design of structure for small watersheds (1 to 25 sq. mi.), however, with increasing urbanization of many parts of Maine , numerous examples indicate land use is indeed having significant impact on watersheds in this size range. This study will use actual stream flow data from two sites coupled with historic land use data to develop a new methodology for calculating flows at these types of urbanized watersheds. The United States Geological Survey, Maine Division, will provide gauged stream data equipment and data, analytical skills, and other research services.

RESEARCH PEER EXCHANGE The MaineDOT Research program cooperates in a peer exchange which concentrates on the Research, Development, and Technology Transfer management process. MaineDOT hosts peer exchange within this program.

Page last updated: September 26, 2005