bluuebunny/crossref_metadata_2025 huggingface dataset:
Rehabilitation Study of Toutle River Tied-Arch Bridges
Authors: Leland Amy C. , Brown Nathan S. , Van Lund John A.
Published: April 2007

The Toutle River tied-arch bridges (Br. No. 5/140 E & W) are located on Interstate 5 in western Washington State and were open to traffic in 1969. Approximately 33,000 vehicles a day cross these bridges; 22% are trucks. Large deflections result with the passage of these trucks, causing the bridges to vibrate in the first mode of vibration. A strengthening and stiffening study was conducted to minimize deflection, vibration, and fatigue cracking. Several stiffening methods were analyzed. The addition of diagonal tension members between each vertical hanger and addition of compression members placed near the quarter points of the bridges emerged as the most promising options. The bridges also experience fatigue cracking. The floor-beam webs have cracks at most tie-chord connections and at exterior longitudinal stringer connections. Stiffening the arches would decrease the fatigue stress range in the tie chord. Retrofitting the floor system to accommodate thermal movements would minimize distortion-induced fatigue in the floor beams. At the bridge bearings, extensive cracking is present at the fillet welds connecting the upper bearing blocks to the tie chord. A bearing replacement was recommended. Adding post-tensioning strands to the tie chord was also recommended as a safeguard against sudden failure. Estimated retrofit costs were also developed.
Precast Posttensioned Abutment System and Precast Superstructure for Rapid On-Site Construction
Authors: Scanlon Andrew , Aswad Alex , Stellar James
Published: April 2007

A prefabricated bridge system was designed to minimize on-site construction time. The system consists of a double-cell adjacent box beam superstructure supported on precast posttensioned abutment units on cast-in-place footings. The design concept was implemented in a demonstration bridge replacement project, a single-span bridge crossing a creek in southwestern Pennsylvania. The construction project demonstrated the feasibility of the design concept as a means to reduce construction time by eliminating cast-in-place concrete for abutment walls.
Designing Discontinuity Regions in Structural Concrete with Computer-Based Strut-and-Tie Methodology
Authors: Kuchma Daniel A. , Tjhin Tjen N.
Published: April 2007

The strut-and-tie method (STM) was introduced in 1994 in the AASHTO load and resistance factor design specifications. Within the strut-and-tie design approach, an internal truss, consisting of concrete struts and steel ties, carries the loadings through the D-region to its supports or boundaries. To create this truss, reinforcing or prestressing steel is selected to serve as the ties, whereas dimensions for struts and joints (nodal zones) are chosen so that they have sufficient strength. The STM design process typically requires selecting an appropriate internal truss, adjusting and refining the truss, and conducting multiple truss analyses, for different load combinations. Completing this design process by hand can be time consuming. The computer-aided strut-and-tie (CAST) design tool is being developed to overcome this challenge. CAST provides a single graphical interface that enables the designer to sketch and analyze the idealized truss, to select member dimensions and tie reinforcement, to readily adjust all design variables, and to create a printout of the final design.
Risk Analysis as Design Tool in Fire-Safety Retrofit of Two Italian Tunnels
Authors: Mammino Armando , Tonon Luigi , Tonon Fulvio
Published: April 2007

A fire-safety retrofit was designed for two existing road tunnels in northern Italy. The design alternatives are compatible with the local geomorphology and the existing portal infrastructures. To assess the risk associated with the current condition and the design alternatives, a risk analysis procedure was implemented based on the FHWA report Prevention and Control of Highway Tunnel Fires. Because no Italian code or recommendation exists on this subject, it was necessary to tune the U.S. document to the Italian and local conditions. This risk analysis allowed both the designer and the client to assess the benefits of the design alternatives with respect to the current condition and to compare the design solutions, thus providing invaluable help in the decision-making process. The two proposed solutions increase the probability of no fatalities from zero (current state) to 64% and 68%, respectively.
Classification of Damaged and Modified: Bridge Beams with Vibration Signatures
Authors: Owen J. S. , Pearson S. R. , Tan C. M. , Choo B. S.
Published: April 2007

A modal survey was performed on eight posttensioned reinforced concrete beams removed during the demolition of a highway bridge in the United Kingdom. The aim of the study was to continue investigations into using vibration data for the structural health monitoring of bridges. The use of modal data to distinguish between beams with different damage levels and between modified and unmodified beams was inconclusive. However, there were clear differences in the shape of the measured frequency response functions (FRFs), which suggested that this might be a better classifier. The method of principal component analysis was used to reduce the FRF data dimensionality, and when this was done, it was possible to clearly distinguish between damaged and modified beams using only a two-dimensional feature vector. To distinguish between beams with different damage levels, feature vectors with more components were used in conjunction with a generalized linear artificial neural network. This approach successfully classified the beams according to damage level, although more beams need to be tested to improve the reliability and general applicability of the method.
Corrugated High-Density Polyethylene Pipe: Laboratory Testing and Two-Dimensional Analysis to Develop Limit States Design
Authors: Dhar Ashutosh S. , Moore Ian D.
Published: April 2007

Baseline data on buried thermoplastic pipe behavior under biaxial loading have been developed in a controlled laboratory environment. Deflections and local wall strains of a lined corrugated high-density polyethylene pipe were determined. Use of the finite element method and simplified design equations was then evaluated relative to the laboratory measurements. Measurements of soil response during the tests were used to evaluate the constitutive response for the soil. The comparisons reveal that the two-dimensional finite element method can effectively be used to predict pipe deflections and circumferential strains in the corrugation, given that appropriate material parameters are used. Liner strains, however, are influenced by local bending, so that three-dimensional analysis is required. The simplified design methods were shown to be effective tools for pipe design. A strain factor of three in the semiempirical equation for circumferential bending strain appears to be reasonable for pipes buried in uniform ground. The finite element method was then used to study lined corrugated pipe response when the zones of backfill placed beneath the haunches have low density and modulus. These alter the location of the peak strains, may significantly increase the magnitude of the circumferential strains and the strain factor, and induce yield at the extreme fibers.
Field Measurements of Long-Span Corrugated Steel Culvert Replacing Corroded Concrete Bridge
Authors: Vaslestad Jan , Madaj Arkadiusz , Janusz Leszek
Published: April 2007

Field measurements were carried out on a steel culvert in Poznan in Poland. The steel culvert is a pipe arch with a span of 8.9 m, a height of 7.76 m, and a soil cover of 1.8 m. This road culvert and a parallel pedestrian steel culvert were used to replace a severely corroded concrete railway bridge. The steel culverts were erected and backfilled without closing busy track railway. The steel culverts were instrumented to measure steel stress and deformations during backfilling and load testing. Two locomotives with a total weight of 2360 kN were used for load testing. The measured steel stress and displacements during load testing were recorded with the locomotives placed at various locations (static) and also during braking. The steel stress and deformations from live loading were small compared with the steel stress and deformations during backfilling. The measured steel stress from live loading was less than 7 MPa, and displacements were less than 0.5 mm. The measurements also show that long-span pipe arches perform well without longitudinal thrust beams and circumferential stiffening ribs. Long-term measurements were also taken in the period after the end of construction from March 1998 until December 2000 and indicated very good performance of the structure. The structure received a prize for engineering excellence due to innovative construction and aesthetic appearance.
Performance Evaluation of High-Density Polyethylene Culvert Pipe
Authors: Gassman S. L. , Schroeder A. J. , Ray R. P.
Published: April 2007

A study has been performed to evaluate the field performance of existing high-density polyethylene (HDPE) pipe used for drainage applications on highway projects. Forty-five HDPE pipes were inspected at sites in South Carolina. The sites were statistically selected based on geographical location, pipe diameter, use, and age, and the condition of each pipe was not known before selection for inspection. Pipe performance was evaluated with respect to AASHTO and ASTM specifications, measurements of pipe deflection with a mandrel set to 5% deflection, and visual inspections using a video camera. The video camera inspections revealed circumferential cracks in 18% of the pipes, localized bulges in 20% of the pipes, and tears or punctures in 7% of the pipes. Deflections greater than 5% were observed in 20% of the pipes. Most of this observed damage was considered minor because the pipes were maintaining a relatively round shape with limited structural distress and still performing near to the original installation purpose. Installation problems such as poor preparation of bedding soils, inappropriate backfill material, and inadequate backfill cover contributed to the excessive deflection and observed internal cracking in pipes with observed damage. More pipes backfilled with Class IV soils did not pass the mandrel test than those backfilled with Class II or III soils. In addition, cracks were more apparent in Class IV backfilled pipes than they were in pipes backfilled with Class II or Class III soils. Forty-four percent of the pipes had less than the recommended height of soil cover. Appropriate installation procedures are essential to achieving high-quality performance.
Profile-Wall High-Density Polyethylene Pipes 1050 mm in Diameter Under Deep Soil Cover: Comparisons of Field Performance Data and Analytical Predictions
Authors: Sargand Shad M. , Masada Teruhisa , White Kevin E. , Altarawneh Bashar
Published: April 2007

Although the study of pipe–soil interaction has more than 80 years of history, a lack of long-term field performance data still exists when it comes to the structural performance of large-diameter, profile–wall thermoplastic pipes under deep soil cover. Field-monitored structural performance data were taken for 1050-mm (42-in.) diameter, corrugated high-density polyethylene (HDPE) pipes, which were subjected to 6.1-m (20-ft) and 12.2-m (40-ft) soil fill heights at the ORITE deep burial test site at the Ohio Research Institute for Transportation and the Environment. The field data accumulated over about 2 years indicate that these HDPE pipes are performing satisfactorily. None of the pipes deflected more than −2.5% vertically and 1% horizontally. Closer examinations of the field data obtained at the end of construction and a few months afterward provided insights into the HDPE pipe performance under deep soil cover. Among the analytical methods evaluated in light of the field data, the elastic solutions established by Burns and Richard were most promising in predicting the field performance of the HDPE pipes under deep soil fill.
Energy Efficiency Strategies for Freight Trucking: Potential Impact on Fuel Use and Greenhouse Gas Emissions
Authors: Ang-Olson Jeffrey , Schroeer Will
Published: April 2007

Trucking is the dominant mode of domestic freight and offers a substantial opportunity to improve transportation energy efficiency and reduce the emission of criteria pollutants and greenhouse gases (GHGs). In response, the Environmental Protection Agency (EPA) is proposing the voluntary Ground Freight Transportation Initiative, which will work with all industry sectors associated with freight movement as well as local governments to improve efficiency and reduce emissions through a range of voluntary actions. These actions may include best management practices, operational improvements, and advanced technologies. Strategies that EPA and partners will investigate as potential measures that could improve the environmental performance and energy efficiency of one subsector of ground freight, the trucking sector, are explored. Eight trucking strategies are assessed, including technological innovations and humanfactor (operations) strategies. All are commercially available (or, for operations, feasible) today, but most have achieved little market penetration. Each strategy is briefly described, and each strategy’s impact on the fuel economy of a typical freight truck is assessed. Then estimations of the current and potential maximum market penetration of each strategy as well as the potential reductions of U.S. GHG emissions resulting from national adoption of the strategy are presented. At a national participation rate of 50%, the total maximum benefit of the initiative in 2010 would be a reduction of 3.0 billion gallons of fuel and 8.3 million metric tons of carbonequivalent emissions.
Freight Activity and Air Quality Impacts in Selected North American Free Trade Agreement Trade Corridors
Authors: Ang-Olson Jeffrey , Cowart Bill
Published: April 2007

The current and future air quality effects that result from the development of North American trade and transportation corridors are examined, and strategies to mitigate these impacts are explored. The analysis focuses on five specific binational corridor segments. For each segment, commodity flow and ground freight traffic volumes (truck and rail) are used to develop a sketch-level estimate of current air pollution emissions associated with cross-border trade. Cross-border freight is responsible for 3% to 11% of all emissions of nitrogen oxides and 5% to 16% of all emissions of particulate matter smaller than 10 μm (PM10) from mobile sources in the corridor regions. Trade forecasts to 2020 are used to develop a sketch-level estimate of future trade-related emissions. Carbon dioxide emissions from cross-border trade will increase 2.4 to 4 times over current levels in the five corridors. As a result of the expected improvement in criteria pollutant emissions controls for trucks and locomotives, total trade-related emissions of nitrogen oxides and PM10 in 2020 will be lower than or the same as current levels, despite increased trade volumes. The effects of six emissions mitigation strategies are also discussed.
Estimating International Roughness Index from Pavement Distresses to Calculate Vehicle Operating Costs for the San Francisco Bay Area
Authors: Dewan Shameem A. , Smith Roger E.
Published: April 2007

Incorporating models that estimate road user costs and user benefits or both from different management strategies would increase the road network asset management system capabilities. Vehicle operating cost (VOC) can be a major part of road user costs, and pavement surface roughness is a major factor that affects VOC. This study was based on an effort to establish a correlation between pavement roughness and pavement distresses for asphalt concrete surface with the objective that the developed roughness model could be utilized to estimate VOCs for the streets in the cities and counties of the San Francisco Bay Area directly from pavement distresses. Due to the lack of roughness data for Bay Area city streets, Strategic Highway Research Program distress data for California Long-Term Pavement Performance sites were used as an initial effort to establish the model. A systematic approach was used to come up with a reasonable correlation between international roughness index (IRI) and pavement condition. The current roughness model can be used to estimate surface roughness if the pavement surface distress data are available. This model could be included, along with an additional incorporation of established relations between VOC and IRI, in the Bay Area agencies' pavement management system, to estimate VOC directly from pavement distresses. Finally, some recommendations are provided to the agencies in the Bay Area cities and counties on how to utilize the model and how to refine the initially established model in the future.
Multicriteria Analysis Method for Pavement Maintenance Management
Authors: Cafiso Salvatore , Di Graziano Alessandro , Kerali Henry R. , Odoki J. B.
Published: April 2007

Multicriteria analysis (MCA) provides a framework for breaking a problem into its constituent parts. MCA provides a means to investigate a number of alternatives in light of conflicting priorities. By structuring a problem within the MCA framework, alternatives may be ranked according to preestablished preferences to achieve defined objectives. A method developed for providing an MCA framework within the Highway Development and Management Tools, Version 4 (HDM-4) is described. Factors such as social benefits, environmental effects, safety impact, strategic importance of roads, and so forth have been included, within a unified decision-making framework. The analytic hierarchy process method was selected for HDM-4 because it transforms the analysis of competing objectives to a series of simple comparisons between constituent elements. The approach does not require a definition of trade-offs between the possible values of each attribute (i.e., it is not necessary to build utility functions), and it allows users to understand how outcomes are reached and how weightings influence outcomes. A pilot implementation checked the applicability of the analytical hierarchy process (AHP) method to road management and analyzed the effectiveness of outputs. Results obtained using HDM-4 economic criteria were compared with those produced by AHP. For the pilot implementation, the HDM-4 strategic planning application was chosen because it is the level in which, generally, medium- or long-term programs must be defined along with economic and other social and environmental aspects to justify budget allocations. Five main criteria were identified with regard to road maintenance budget allocations that constrain the decision-making process: comfort, environment, safety, road agency costs, and road user costs. Prioritization based on MCA more evenly distributes the available budget when compared with prioritization based on economic criteria, which tends to favor roads with high volumes of traffic.
Survey of State Law Enforcement Personnel on Work Zone Enforcement Practices
Authors: Schrock Steven D. , Ullman Gerald L. , Trout Nada D.
Published: April 2007

An important first step in maximizing the effectiveness of work zone law enforcement is to determine how officers operate. Although transportation professionals may understand the benefits of different enforcement strategies, does this translate to improved enforcement methods in the field? A survey was developed and administered to determine the problems encountered by various state law enforcement agencies when enforcing work zones. The survey was also an attempt to identify areas of improvement and innovative practices worthy of further development. State law enforcement agencies from 20 states were contacted by telephone to determine how work zones were enforced in their respective states. Officers were asked questions regarding funding for work zone enforcement; techniques used by law enforcement at work zones; locations in or near work zones where officers are typically stationed; the level of coordination between law enforcement, the state highway authority, and the construction contractor; and initiatives that helped maximize the effectiveness of law enforcement in work zones. A strategy identified in this research was the formation of specialized units to patrol work zones and to train other officers to effectively patrol work zones. A second strategy allows local law enforcement officers and retired officers the opportunity to enforce work zone practices on state roadways to overcome a chronic shortage of available officers.
Modal Shift Mechanism in the Transition Period from Bicycle User to Automobile User
Authors: Koike Hirotaka , Morimoto Akinori , Takekoshi Yoshinori , Sarker Mohsin
Published: April 2007

As motorization spreads worldwide, concern is growing about the adverse effect of automobiles on energy resources and global environmental problems. A way to alleviate excessive dependency on automobiles is to promote bicycle transportation. However, it is difficult to increase bicycle usage except in some European countries, such as the Netherlands. In Japan the bicycle is commonly used from childhood through high school, but a rapid shift to the automobile takes place at college age. College students were surveyed by questionnaire on their bicycle use patterns and automobile ownership, along with bicycle use in their hometowns. The statistical analysis shows various relationships among population size of hometowns, regional characteristics, individual favoritism toward bicycles, financial condition, and so on. A clear difference was found between two groups of hometown regions for present bicycle usage patterns: those from large metropolitan areas and those from smaller regions. The transportation systems in cities and different population sizes influence bicycle use and favoritism toward bicycles, which in turn affects the present bicycle use level. Finally, the study reveals four factors that affect the modal shift from bicycle user to automobile user during the college-age period: physical environment, financial aspects, past experience, and favoritism toward bicycle use. These factors should be incorporated in designing bicycle transportation policy in urban areas.
Observing the Basics: Remembering Wilfred Owen
Authors: Betz Mathew J.
Published: April 2007

The conference presents a unique opportunity to recognize the contributions of Wilfred Owen to the field of low-volume roads and their application to the problems of today and tomorrow. Owen was the transportation expert for the Brookings Institution for about four decades. Besides being interested in the theories and principles of low-volume roads, Owen was vitally concerned with the rural and urban needy throughout the world. He believed that the development of transport and the economic opportunities that would ensue would benefit them significantly. Few have had more impact on the provision and improvement of low-volume roads in developing countries than Wilfred Owen. He was the author of many studies of specific countries in addition to several books. His major emphasis was on the need to identify and grasp the basics of economic evaluation and, more important, the basic premises and goals for investing in transport to facilitate economic development. Owen’s second major emphasis was on well-founded and rational planning. He focused on the need for change, including the reorganization of international efforts to address the global transportation problem. In 1983 Wilfred Owen was the keynote speaker at the Third International Conference on Low-Volume Roads. His topics that day included a shrinking planet, integrated global economies, world population growth, global disparities, and development of an international cooperative effort. He had completed his last book shortly before his death in November 2001.
Rural Transportation Infrastructure Preservation in Kansas: Issues and Challenges
Authors: Hossain Mustaque , Romanoschi Stefan A. , Emig Larry W.
Published: April 2007

Rural transportation infrastructure, owned and maintained largely by local governments, has a unique role in the mobility of the United States. Local transportation infrastructure is maintained mostly by property taxes. Federal assistance for local governments for rural infrastructure preservation is minimal. Cities and counties across the state of Kansas have an enormous task in maintaining their roads and bridges: 90% of the roads and 80% of the bridges in the state are their direct responsibility. According to the U.S. Census Bureau, between 1990 and 2000, 59 of the 105 counties in Kansas lost population, some as much as 14%. Adequate funding for transportation infrastructure is the biggest concern in the counties where population is decreasing, followed by maintenance and rehabilitation issues. Some counties with falling population have experienced a decrease in travel in terms of average daily vehicle miles traveled. However, truck travel increased in some counties, which resulted in deteriorated pavements. Very little data exist to assess highway and bridge maintenance needs. An asset management system for the counties would be ideal to assess current and future needs. Rural transportation infrastructure development should be part of regional plans for economic development. Although the number of structurally deficient and functionally obsolete bridges is higher on the county roads than on the city or state routes, no separate funding exists for local bridges in Kansas. More federal assistance in this area is also urgently needed.
Private–Public Partnership for Low-Volume Roads: Swedish Private Road Associations
Authors: Ivarsson Sven , Calvo Malmberg Christina
Published: April 2007

Unit costs for low-volume road construction and maintenance are low compared with those for higher-level roads. The problem is that in many countries this network is vast, and the total cost requirements to ensure minimum access are enormous. This problem is a particular challenge in developing countries where more than two-thirds of the poor reside in rural areas. The option of private ownership and financing of low-volume roads is proposed. It is argued that the Swedish model for low-volume road management and financing is simple and efficient and can easily be adapted to a variety of circumstances in both rich and poor countries. In Sweden, private road associations manage two-thirds of the road network at less than half the cost and with better results than do the government road agencies. This model is based on a well-structured institutional framework for private ownership of low-volume roads that includes a law on private roads and financial and technical incentives. The government provides legal and financial incentives for local property owners to associate and assume responsibility for their roads. The result is a private–public partnership in which government subsidizes road costs with grants from the budget. Increasing efficiency and effectiveness of public expenditures and working in partnership with the private sector are highly relevant goals in both developed and developing countries.
Turning Deteriorated Paved Roads Back into Gravel Roads: Sheer Lunacy or Sustainable Maintenance Policy?
Authors: Mustonen Jyri , Lintilä Janne , Mäkiö Tauno
Published: April 2007

In the late 1980s, many Finnish low-volume gravel roads were paved. This option was reasonable at that time because the price of bitumen was exceptionally low. No heavy structural rehabilitation was carried out on these roads before paving. It was assumed that these cheap and light pavements would last some 5 years. Now many of those roads have reached 10 to 15 years in age, still without any proper reconstruction, and are becoming increasingly deteriorated. For almost a decade now, the Finnish government has been reducing its spending on public roads. Maintenance and repair efforts have been concentrated on the main road network, and the minor network has deteriorated more and more. Calculations show that from the road agency’s point of view, upkeep of gravel roads is economically feasible compared with maintaining paved roads that are in poor condition. Therefore, road authorities have converted some of these paved low-volume roads back to gravel roads. In 2001, the Häme, Turku, and Uusimaa road districts agreed on common principles for these actions. Furthermore, they described minimum requirements for each case in which a paved road in poor condition was turned into a gravel road. Public opposition and political resistance were quite strong before these actions, since the gravel roads are seen as a decline of service level. People living along the road, however, generally admit that new gravel roads are more comfortable to drive on throughout the year than old deteriorated pavements. The road agency still has to focus on problems such as dust.
Engineering and Legislative Options for Improved Timber Haulage in Scottish Forests: Inclusive Stakeholder Approach
Authors: Killer D. , Paxton S. , Dawson A.
Published: April 2007

The forest industry in Scotland depends for its economic survival on the efficiency with which it can get the felled timber to the mill. This efficiency is shown to depend on pavement quality, particularly the aggregates used; the truck fleet available to extract the timber; and the interaction of these two factors and the legislative regime, including taxation, under which the forest traffic operates. Although there is a high degree of cooperation within the forest industry—pavement constructors, haulage companies, public and private forest owners, and local government authorities—there is need for a more comprehensive assessment of the interaction of the various factors affecting the forest timber haulage operation. This interaction has been studied in a preliminary manner using a specific highway management tool, HDM-4. Vehicle use regulations and taxation and their application are shown to be particularly constraining on the overall efficiency of the operation.
Integration of Comprehensive Environmental and Social Measures into Low-Volume Road Design for the Hills of Nepal
Authors: Corbett Matt , Gaviria Juan
Published: April 2007

Road construction through Nepal’s hilly and mountainous terrain has historically had a significant impact on the local environment and land-owners, primarily because of the steep and often unstable terrain traversed, monsoonal climate, necessity for low-cost roads, and no landowner compensation for compulsorily acquired land. The design phase of the Road Maintenance and Development Project sought to incorporate comprehensive environmental and social measures into the design of low-cost roads in the western hills of Nepal to achieve more stable and lower-impact roads. The project involved the design of 196 km of new roads and 253 km of upgrading to existing roads by integrating engineering, environmental, social, and economic factors throughout the design process. The project began with the screening of candidate project roads on the basis of economic, environmental, and social factors by using a weighted scoring system to select those roads that would be most advantageous in relation to passenger and goods transport and associated economic development, while minimizing adverse environmental and social impacts. Proposed new road alignments were refined primarily through a walkover survey by a multidisciplinary team, ensuring that environmental and social issues were incorporated into this key stage of road design, when significant impacts can be avoided. Detailed road design incorporated comprehensive environmental management and social planning through integrated planning. Project outcomes include road designs that would increase road stability and have fewer construction impacts and the first comprehensive land and property compensation program for road construction in Nepal.
Cutting Red Tape and Pollution from Unpaved Roads by Using a Geographic Information System
Authors: Bloser Steven M. , Colbert Woodrow J.
Published: April 2007

A case study in the implementation and use of a customized geographic information system (GIS) as an administrative tool is described. A modified GIS is being used to provide full administrative support for a $ 4 million/year transportation grant program with a single part-time support staff person in the central office. Pennsylvania’s Dirt and Gravel Road Pollution Prevention Program was enacted into law as Section 9106 of the State Vehicle Code in 1997 and is administered locally through county-based soil conservation districts. The program uses a simplified and customized GIS that enables personnel at 65 county conservation districts to use the system with minimal training. The customized GIS enabled a statewide assessment of more than 17,000 mi of unpaved roads to be conducted in 6 months. That assessment geographically identified and evaluated more than 11,000 pollution sites at which unpaved road runoff adversely affects stream quality. Pollution site assessments, record keeping, and reporting have been incorporated into the modified GIS to provide paperless, centralized reporting in keeping with the program’s core values—streamlined administrative structure, emphasis on local control, and effective prevention of stream pollution from dust and sediment generated by unpaved roads. The value that a customized GIS can have for similar applications is illustrated by providing a walk-through of how the system works, why it has been accepted, and what it accomplishes for this innovative non-point-source pollution prevention effort.
Improving Unpaved Roads in Virginia: Case Study
Authors: Dunn Michael W. , Noelle On S.
Published: April 2007

Minimizing costs and streamlining the construction of low-volume roads offers an opportunity for transportation agencies to effectively meet the needs of rural citizens. The Virginia Department of Transportation (VDOT) maintains approximately 56,941 mi of the state’s roads, including Interstate, primary, and secondary facilities. Between 1987 and 1994, VDOT paved nearly 1,900 mi of unpaved roads. In rural parts of the state, many miles of state-maintained roads still have gravel and dirt surfaces. Each year the local transportation residency offices, in conjunction with local elected officials, contractors, and area citizens, strive to improve and pave as many miles of gravel and dirt roads as possible. The Hillsville Residency of VDOT, located in rural Carroll and Floyd Counties, has developed an efficient and cost-effective method for improving low-volume gravel and dirt roads. This process relies heavily on cooperative efforts by VDOT, contractors, elected officials, and especially citizens. Land donations from citizens represent the cornerstone of this process, signifying that citizen cooperation is the key factor in a project’s success. Because most of the decisions in the improvement process are at the local residency level, trusting relationships and frequent communication can be established, small-scale and local contractors are given more business opportunities, and local VDOT personnel can better understand citizen concerns and perform road improvements accordingly. In addition, the time line for the road improvement process is based on seasons—the most appropriate weather conditions are considered for the work being performed. This program enables more roads to be paved each year, improving the level of service and quality of life for local citizens.
Rural Rustic Roads in Virginia: Implementation of Program Guidelines and Pilot Projects
Authors: Givens James S.
Published: April 2007

The legislative process and development of guidelines for a rural rustic road program in Virginia are described. As defined in the legislation, a rural rustic road “. . . (i) is located in a low-density development area and has an average daily traffic volume of no more than 500 vehicles per day and (ii) has a posted speed limit consistent with the topography and features along the road. For a road or road segment so designated, improvements shall utilize a paved surface width based on reduced and flexible standards that leave trees, vegetation, side slopes and open drainage abutting the roadway undisturbed to the maximum extent possible without compromising public safety.” This new program is designed to pave unpaved roads by using their existing alignment wherever practical. This approach will preserve the natural beauty and character of the area served.
Economic Fish Passage: An Innovative Alternative
Authors: Showers Charles G.
Published: April 2007

Many existing stream-crossing structures on low-volume roads were designed and constructed to pass the design flow. Many of these structures are large-diameter metal culverts that are mechanically sound and still sufficient for the volume of traffic and the design vehicle as well as the maximum designed stream flow. However, design of these structures often gave no thought to the migration or mobility of aquatic species, particularly fish. Continued existence of many aquatic species requires that habitat fragmented by development be reconnected, specifically stream segments separated by road-crossing structures such as large culverts. The user cost–benefits and revenues available to the low-volume road manager make full replacement of existing structures prohibitive and difficult to justify, especially when the existing structure is sufficient for the traffic need. An effective, economic alternative to the removal of large culverts is offered, one that can be implemented with commonly acquired equipment and labor, with costs kept reasonably low in meeting the objective of reconnecting segments of aquatic habitat.
Evaluation of a Low-Cost Program of Road System Traffic Safety Reviews for County Highways
Authors: Ford Stephen H. , Calvert Eugene C.
Published: April 2007

Mendocino County is a large rural county in northern California with more than 1,000 centerline miles of county-maintained roads. The terrain is mountainous, with a few small inland valleys. During the 1990s, the Mendocino County Department of Transportation developed a program of road system traffic safety reviews to improve signing and markings on the arterials and collectors in the system. The effectiveness of the program was measured by comparing accident data for the reviewed roads with data for roads not included in, or influenced by, the reviews. To control for different groups of factors, two sets of control roads were selected—county-maintained roads not reviewed and state highways within the county. Over two consecutive 3-year review cycles, the number of accidents on the reviewed roads fell by 42.1%, while on the county-maintained roads not reviewed they increased by 26.5%, and on the state highways they fell by 3.3%. The total cost to conduct the reviews and implement the recommended changes was $ 79,300. The accident histories of the control roads were used to define the limits of the range of probable benefits. On the basis of average accident costs provided by the California Department of Transportation, calculated savings ranged from $ 12.58 million to $23.73 million, yielding a costs-to-benefits ratio between 1:159 and 1:299. The county is expanding the road system traffic safety review program to cover its entire maintained road system.
Real-Time Detection of Unsealed Surfaces During Skidding
Authors: McManus Kerry J. , Blicblau Aaron S. , Broadhurst Christopher J. , Carter Ashley M. S.
Published: April 2007

The antilock braking system (ABS) fitted to modern passenger vehicles is intended to provide reliable and efficient braking under critical road conditions or in emergency situations. Thus, ABS-equipped vehicles should remain steerable and maintain directional stability in the event of emergency braking. The ABS on vehicles operates on the principle of detection of brake lockup and release of the lockup to prevent an uncontrollable skid developing on sealed roads. However, on gravel roads or snow-covered roads braking distances can be reduced if brake lockup occurs and a wedge of gravel or snow is allowed to form in front of the wheels. The intervention of ABS prevents the wedge from forming to any significant degree, thereby extending the braking distance. An investigation was carried out of a method of discriminating between sealed and unsealed road surfaces in which a signal can be developed so that an alternative ABS algorithm can be applied specifically for gravel-covered surfaces. An attempt was made to identify and measure the buildup of gravel in front of the wheel directly, using an infrared distance-measurement sensor. Initial tests have shown that the system can provide a signal to the ABS, which will allow a timely response to enable intervention in the activation of the algorithms in the ABS.
Traffic Effects of Fairs and Festivals on Low-Volume Roads
Authors: Eck Ronald W. , Montag Daniel A.
Published: April 2007

Special events, including sporting events, concerts, historical re-enactments, and fairs and festivals, can generate large volumes of traffic such that congestion and associated problems occur on low-volume roads. In particular, theme-oriented fairs and festivals, such as arts and crafts fairs and wine and jazz festivals, are growing in number and popularity throughout the United States. Quantifying and understanding the traffic characteristics of fairs and festivals would be useful in predicting how such events will affect traffic flow on a low-volume road, planning traffic management, and predicting parking needs. One specific need is for trip-generation data for estimating the magnitude and nature of travel associated with theme-oriented fairs and festivals. Background data were collected for a number of West Virginia events on low-volume roads through interviews and questionnaires. Five categories of theme-oriented fairs and festivals were identified: food and drink, arts and crafts, cultural heritage, historical, and performing arts. The number of booths was recommended as the best independent variable to use in calculating trip-generation rates. Attendance and vehicular data were collected and analyzed. Vehicle occupancy for theme-oriented fairs and festivals was determined to be 2.33 people per vehicle. Trip-generation rates and corresponding statistics were determined for 2-day (Saturday and Sunday) and 3-day (Friday, Saturday, and Sunday) events. Implications of the study results for low-volume road managers were considered.
Road Maintenance with Opti-Grade®: Maintaining Road Networks to Achieve the Best Value
Authors: Brown Mark , Mercier Steve , Provencher Yves
Published: April 2007

Road management systems rely on the availability of quality information to make good decisions. A lack of information on the condition of the Canadian forest industry’s unpaved road network led to inappropriate management decisions. To fill this information gap the Forest Engineering Research Institute of Canada (FERIC) developed the Opti-Grade road management system. Opti-Grade is a low-cost tool that provides information about the road roughness and travel speed as the equipped road user’s vehicle travels on the road network. This information can then be used to focus grading activities where they will have the greatest impact on the road condition for the money invested. Further, over time, a history of the behavior of the roads can be built. With this history, degradation models can quickly and easily be produced to see which segments of the road network degrade the quickest and the most frequently. Problem segments can be identified. Valuable road evaluation budgets can then be focused on those sections to determine the cause of the problem. That will allow precious rehabilitation budgets to be focused where they can have the greatest impact. Opti-Grade is currently used by a large sector of FERIC member forest companies with payback periods shorter than 4 months. FERIC continues to improve the software to manage the data from the Opti-Grade system and increase the abilities of the decision support tools in the software.
Project-Level Highway Management Model for Secondary Highways in Saskatchewan, Canada
Authors: Safronetz Joshua D. , Sparks Gordon A.
Published: April 2007

Saskatchewan Highways and Transportation (SHT) is responsible for 26,000 km of primary and secondary highways in the province. The primary system was structurally built to handle high traffic volumes and heavily loaded trucks; the secondary system was constructed to provide links into the primary system for traffic volumes lower than 500 vehicles per day with few heavily loaded trucks. Secondary highways consist mostly of thin membrane surface (TMS) highways, which are oil-treated surfaces over a nonstructural roadbed. In the past few years increased heavy-truck traffic associated with rail line abandonment, elevator closures, and increased truck haul associated with economic development has deteriorated TMS highways. Years of increasing pressures and inadequate funding have forced SHT to develop and implement cost-effective, sustainable methods to manage and preserve them. A new strategy to structurally strengthen the system is a cementitious blend of material called TerraCem. Along with conventional strengthening strategies, this new method is being used throughout Saskatchewan; however, its long-term performance is unknown. Because SHT must make good decisions and should be able to demonstrate they are good, a project-level framework capable of evaluating secondary road management strategies on the basis of whole life-cycle road agency and road user costs, has been developed. The framework determines the lowest-cost strategy (agency and road user) and employs probabilistic modeling to quantify the long-term performance of the TerraCem strategy. The developed framework was applied for a project-level sample.
Development of Real-Time Mine Road Maintenance Management System Using Haul Truck and Road Vibration Signature Analysis
Authors: Thompson Roger , Visser Alex , Miller Rusty , Lowe Ted
Published: April 2007

The unpaved road network of a surface mine is extensive, comprising numerous roads of varying construction and material qualities with highly variable traffic volumes. Existing haul road maintenance management systems (MMSs) work well for predictable traffic volumes, but for complex mine road networks, the MMS becomes onerous and results in suboptimal road maintenance strategies, with the attendant increase in total road-user costs and reduction in service. A real-time MMS was thus sought to overcome the deficiencies of existing systems for mine roads. Because most large mines operate trucks with onboard diagnostic data collation, linked through a centralized communication and Global Positioning System backbone, it was proposed that road condition could be monitored on a real-time basis through onboard vibration signature analysis. A real-time mine haul road MMS was developed. Mine road maintenance practices were reviewed. The real-time system architecture was devised, and a field trial was conducted of onboard vibration signature assessment. Trial results were evaluated in the light of road defect signature recognition, analysis, signature repeatability, and system limitations. This approach is applicable to other situations, such as a network of district roads, subject to an analysis of economic feasibility. The conclusion is reached that modern technology has the potential to apply maintenance as and where needed, with possible reductions in authority cost and an improvement in service provided to road users.