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Because intellectual property is a dynamic field of law, this handbook is neither a, comprehensive guide nor an accurate predictor of legal developments. This handbook, is merely an effort by the Virginia Transportation Research Council to provide VDOT, employees guidance in addressing the intellectual property issues they may face during, the scope of their employment. This handbook is not a substitute for professional legal, advice. If you need more detail concerning your individual rights and duties, you should, consult an attorney., This handbook will be reviewed annually and revised periodically as warranted, by changes in the law and governmental policy. This updated handbook is intended to, replace the March 2002 edition. The organization of the handbook was modified to, focus on intellectual property issues related to VDOT.

The second Strategic Highway Research Program (SHRP2) developed data and analysis tools to improve the measurement and management of travel time reliability by transportation practitioners. The SHRP2 Program provided funding to help agencies test the tools and incorporate reliability into their business practices.

The Run-off-the-Road(ROTR)type of accidenthas beena predominantfactor in highway, fatalities nationwide. This situation has created a major concern and challenge for traffic, management within transportation departments. Shoulderrumble strips are new traffic control, devices for interstate and limited access roadway systems, which hold great potential for, reducing ROTR accidents. Consequently,they have becomea critical and attractive subject for., highway safety improvements., Although shoulder rumble trips have been recognizedas an effective measure and have, been widely tested by 35 state agencies and several countries, the rolled type rumble strip is, found most often in the literature. The optimal design patterns among the available types and, their effectiveness have not been quantitativelytested and confirmed. This paper reexamines, different typical patterns using field tests, implementation surveys from agencies, and, mathematical analysis. A model has been developed to determine the optimal patterns. The, results reveal that a milled pattern is superior to a rolled pattern for asphalt shoulders in terms, of audibilityand tactility effectiveness,quality controland ease of construction. The corrugated, pattern is practical for concrete shoulders. E\:'idenceis presented that existing implementation, of policy and design criteria for rolled rumble strips shouldbe modifiedand that more research, is needed to determine the degree of effectiveness., This study was sponsoredby the Traffic EngineeringDivisionat the VirginiaDepartment, of Transportation (VDOT).

The adequate spacing and design of access to crossroads in the vicinity of freeway ramps are critical to the safety and traffic operations of both the freeway and the crossroad. The research presented in this report develops a methodology to evaluate the safety impact of different access road spacing standards. The results clearly demonstrate the shortcomings of the AASHTO standards and the benefits of enhancing them. The models developed as part of this research were used to compute the crash rate associated with alternative section spacing. The study demonstrates that the models satisfied the statistical requirements and provide reasonable crash estimates. The results demonstrate an eight-fold decrease in the crash rate when the access road spacing increases from 0 to 300 m. An increase in the minimum spacing from 90 m (300 ft) to 180 m (600 ft) results in a 50 percent reduction in the crash rate. The models were used to develop lookup tables that quantify the impact of access road spacing on the expected number of crashes per unit distance. The tables demonstrate a decrease in the crash rate as the access road spacing increases. An attempt was made to quantify the safety cost of alternative access road spacing using a weighted average crash cost. The weighted average crash cost was computed considering that 0.6, 34.8, and 64.6 percent of the crashes were fatal, injury, and property damage crashes, respectively. These proportions were generated from the field observed data. The cost of each of these crashes was provided by VDOT as $3,760,000, $48,200, and $6,500 for fatal, injury, and property damage crashes, respectively. This provided an average weighted crash cost of $43,533. This average cost was multiplied by the number of crashes per mile to compute the cost associated with different access spacing scenarios. These costs can assist policy makers in quantifying the trade-offs of different access management regulations.

SMA is a gap-graded mix filled with a rich asphalt-fines mastic developed in Europe. In 1991 five states constructed trial sections to determine if satisfactory mixes could be produced in the United States with current materials and high rates of production. This report discusses Virginia's first section, placed in 1992 near Lynchburg. During construction, better equipment was necessary to control the amount of fines contained in SMA mixes. Lack of control in the mix gradation caused variability on the roadway and on routine mix tests conducted during construction. The mix containing the cellulose fiber, Arbocel, has rotted more at stop-lights than the mix containing the polymer, Vestoplast, or the high-stability control mix. However, all mixes continue to perform well. Laboratory creep tests and gyratory shear tests predicted that the control mix and Vestoplast mix would be more resistant to rutting and consolidation under traffic. This investigation and work in other states have improved the current Virginia specification for SMA. The gradation was coarsened, a stiffer asphalt cement was required, and plant equipment that can adequately handle the aggregates was used. With these changes, future installations will perform better than the current dense graded mixes.

This series of observational surveys, to determine child safety seat use in Virginia, began in 1993 at the request of DMV officials. During all 4 years (there was no survey in 1995), data in metropolitan areas were collected at the same locations, at the same time of day and day of week, and according to the same criteria for determining use. In 1997, data collection was added for safety restraint use by occupants 4 to 16 years of age at the request of officials of the Department of Health, which is now responsible for the state's child safety seat program. In addition, data were collected on whether any booster seats in use were being used properly. Seven sites were also added in communities with a population between 50,000 and 100,000 (mid-size cities). For the entire vehicle, the 1997 metropolitan area child safety seat correct use rate was 54.1 %, incorrect use was 17.4%, and non-use was 28.5%. Non-use was greater in the front seats (42.1 %) than in the rear seats (25.2%). The western area had the highest non-use rate (50.0%) and the lowest correct use rate (32.1 %). Non-use and correct use in Northern Virginia, Central Virginia, and Tidewater were similar, with correct use ranging from 53.1% to 58.7% and non-use ranging from 24.8% to 29.1 %. Child safety seat use in the three areas categorized as mid-size cities (Charlottesville, Danville, and Lynchburg) was lower than in the metropolitan areas: correct use was 43.2%, incorrect use was 14.8%, and non-use was 42.0%, with Danville having the highest non-use rate at 61.9%. Non-use was higher in the front seats (66.7%) than in the rear seats (37.7%). Safety restraint/seat belt use by occupants 4 to 16 years old riding in the rear seats was very low. In the metropolitan areas, correct use was 34.9%, incorrect use was 2.3%, and non-use was 62.9%, with the western area having the highest non-use rate (69.3%). In the mid-size cities, correct use was 26.2%, incorrect use was 1.5%, and non-use was 72.3%, rates considerab

102892, Roller-compacted concrete (RCC) is a stiff mixture of aggregate, cementitious materials, and water with zero slump. RCC, is consolidated or compacted in the fresh state by use of a roller with or without vibration. RCC typically is placed with asphalt, paving equipment in thicknesses of 4 to 8 in for pavement application. RCC has gained the attention of the paving industry in, recent years because of its history of low cost, rapid construction, and durable performance. The Virginia Transportation, Research Council conducted this laboratory study to gain familiarity with RCC technology and to develop guidelines for its use, in the field., RCC mixtures were successfully produced in the laboratory using locally available materials, and their properties were, measured. These mixtures achieved compressive strengths around 5,000 psi in 28 days and had properties similar to those of, conventional concrete in terms of compressive strength, modulus of elasticity, modulus of rupture, and splitting tensile strength., A special provision was developed and used in the two field projects. The special provision was subsequently modified based on, the field experience and is provided in the Appendix., VDOT should implement the RCC specification developed in this study for regular VDOT use of RCC. Use of RCC, should be considered in future field applications, particularly where fast construction of rigid (concrete) pavement is needed; an, example of such an area would carry heavily loaded, slow-moving vehicles such as at intersections and access roads to truck or, bus parking areas. VDOT should annually monitor the long-term performance of the two constructed RCC projects reviewed in, this study over a period of at least 10 years. Evaluations should document joint efficiencies for load transfer (through testing with, the falling weight deflectometer), any visual evidence of deterioration of asphalt at joints, and any other general signs of, pavement distress that may occur.

104117, When new agritourism land uses are initially proposed, a lack of data on how many vehicle trips these uses tend to create, (known as trip generation) means that there is limited guidance available for transportation planners and engineers to make, appropriate and sound recommendations regarding entrances and other traffic improvements. Agritourism land uses can include, farm wineries, breweries, distilleries, orchards allowing visitors to pick fruits and vegetables, and farm stands and markets. This, study reviewed existing information about agritourism trip generation rates and conducted data collection and analysis with regard, to these rates at five winery and cidery sites in Virginia. In Virginia, localities have the ability, albeit limited, to regulate special, events held at agritourism sites, so this study looked at non-event trip volumes., Engineers and transportation planners typically use trip generation data from the Institute of Transportation Engineers’ Trip, Generation Manual to determine entrance categories and to recommend street improvements and strategies for safety or capacity., The manual includes trip rates for several uses that could be considered related but that do not exactly represent the range or, character of agritourism uses, with the possible exception of breweries serving a full menu approximating the manual’s definition, of “quality restaurant.” The data reported in the manual for most of these agritourism-related uses had a large degree of, variability. Recent studies of trip generation at wineries, all from California, were also reviewed., Data collected for the five Virginia sites had high variability, but certain independent variables had moderately high, correlations with trips: (1) number of employees, (2) population within a 60-minute drive, (3) households within a 60-minute, drive, and (4) square footage of tasting room. Although based on a small sample size, the results suggest that established retail, wineries/cideries are likely to exceed the Virginia Department of Transportation’s 50-trips-per-day maximum threshold for a “low, volume commercial entrance,” falling instead into the “moderate volume commercial entrance” or the “commercial entrance”, category., Based on the findings of this study, it appears that VDOT’s practice of assuming low trip volumes for agritourism land uses, may result in entrances that are undersized for the amount of traffic they carry. The “moderate volume commercial entrance”, category may be appropriate for agritourism land uses in most cases. In addition, weekday peak hour volumes for the agritourism, land use sites studied did not occur during the weekday peak hours of adjacent streets. Promising site-based variables for Virginia, wineries include square footage of a tasting room and number of employees at peak season, and when no site-based variables are, available other than location, Census-derived variables can provide some information. Additional research could clarify the, findings of this study., Recommendations for VDOT’s Office of Land Use include (1) providing guidance to VDOT’s transportation and land use, directors indicating that retail-focused wineries can be assumed to generate well more than 50 vehicle trips per day at peak season, and (2) investigating possible adjustments to the traffic volume thresholds for the “moderate volume commercial entrance”, category.

The Tom's Creek Bridge is a small-scale demonstration project involving the use of fiber-reinforced polymer (FRP) composite girders as the main load carrying members. It is a simply supported, short-span bridge located along Tom's Creek Road in Blacksburg, Virginia. As a result of discussions among Virginia Tech, Strongwell, the Virginia Department of Transportation, and the Town of Blacksburg, the existing deteriorated superstructure of the Tom's Creek Bridge was replaced with a glue-laminated timber deck on 8 in (20.3 cm) deep pultruded fiber-reinforced polymer beams. The project was intended to address two issues. First, by calculating bridge design parameters such as the dynamic load allowance, transverse wheel load distribution and deflections under service loading, the Tom's Creek Bridge will aid in modifying current AASHTO bridge design standards for use with FRP composite materials. Second, by evaluating the FRP girders after being exposed to controlled laboratory and service conditions, the project will begin to answer questions about the long-term performance of these advanced composite material beams when used in bridge design. A dynamic load allowance, IM, of 0.90 is recommended for the Tom's Creek Bridge. This value is the largest average IM observed and is therefore conservative. This value is significantly higher than those set forth in the AASHTO standards of 0.33 (AASHTO, 1998) and 0.30 (AASHTO, 1996). It is recommended to use a value of L/425 (LRFD Specification) or L/500 (Standard Specification). This value is consistent with AASHTO deflection control criteria for an all timber bridge. It is recommended to use the AASHTO wheel load distribution factors for a glulam timber deck on steel stringer bridge. There is no indication of loss of FRP girder ultimate strength after 15 months of service. Given the low service loads (no more than 10% of the ultimate capacity) and traffic volume the fatigue life prediction model suggests that fatigue will not be

In May 2002, Virginia's Commonwealth Transportation Commissioner tasked his Chief of Technology, Research & Innovation with leading an effort to develop a definitive, consistent, and well-documented approach for estimating the cost of delivering construction projects. A task force that included Virginia Department of Transportation (VDOT) central and district office staff, Virginia Transportation Research Council staff, Commonwealth Transportation Board members, and a metropolitan planning organization member was formed to either locate a well-founded, tested method for estimating project costs that could be adapted for use by VDOT or develop one. The task group found that a VDOT district had been using an estimation worksheet for several years that produced consistent and reliable results for certain types of roadway and bridge construction. The task group determined that no other method examined had the specificity and potential of this tool. The project team expanded the tool by collecting extensive project data and obtaining evaluations of VDOT project management personnel statewide to develop it further. The existing Excel worksheet with roadway and bridge estimates was expanded to include construction engineering, to be applicable for interstates, and to generate estimates for right-of-way and utilities costs. Data on completed projects were collected from all VDOT districts to help calibrate the model further to account for cost variations across the state. The task group also recognized early on that a very strong focus on project scoping was essential to accurate project estimation. A previous VDOT scoping committee had determined that VDOT did not have a consistent, uniform method that was being used statewide to scope projects. As a result, project cost estimates made at the scoping stage often did not hold up over time because key project features were invariably overlooked. The result was inaccurate estimates. Testing of the cost estimation tool was com

Laboratory creep and fatigue testing was performed on five Superpave surface hot-mix asphalt mixtures placed at the Virginia Smart Road. Differences in creep and fatigue response attributable to production and compaction methods were investigated. In addition, changes in creep response resulting from differences in specimen size were evaluated. Further, an evaluation of the effects of loading frequency, presence of rest periods, and specimen location within the pavement on fatigue life was conducted. Creep compliance values were determined using viscoelastic-based calculations, and time-temperature superposition was used to generate mastercurves. Reported creep compliance response models from the literature were found inadequate for accurately describing the creep compliance mastercurves generated during this study. Differences in creep response between specimens of different sizes were found to be due to specimen and test variability, rather than size. An evaluation of the effects of laboratory and plant production and laboratory and field compaction was inconclusive as material variability appeared greater than production or compaction variability. Simple regression models were found to be satisfactory for use in the development of prediction models for fatigue, although test data are necessary for calibration to particular mixture types. No relationships were found between fatigue model coefficients and volumetric properties of the mixtures tested because of the limited range of volumetric properties. Variability in volumetric properties between the mixtures produced at the plant and those produced to match the job mix formula did not significantly influence the predicted laboratory fatigue performance. Laboratory fatigue lives were similar between the laboratory-compacted fatigue specimens and specimens cut from the pavement; differences observed in performance were attributable to different air void contents. Predicted fatigue life was found to be statistically

The Virginia Department of Transportation's (VDOT) Safety Service Patrollers (SSP) use different color uniforms depending on their geographic location. Red jumpsuits are used in the Northern Virginia District, orange jumpsuits are used in the Fredericksburg District and by the Tidewater Tunnel Patrollers, and white shirts and blue pants with a flagger's vest are used in the Suffok District. The purpose of this research was to identify and evaluate various colors and configurations of retroreflective materials for use on the SSP uniform in an effort to maximize employee safety. This study was to recommend a color, or colors; a pattern of retroreflective material; and the type of uniform that should be used as VDOT's standard SSP uniform. The scope of the project was limited to the use of existing materials and colors readily available from vendors. The uniforms selected for testing were evaluated under controlled conditions in the field. This evaluation consisted of photographing the existing SSP uniforms and the two prototypes on a closed portion of roadway with little to no external lighting. Photographs were taken of each uniform under daytime and nighttime conditions. A videotape was used to capture how the uniforms appear while a driver drives toward them during nighttime conditions under low and high beams. The videotape was also used to capture the ergonomic movements of the uniforms and how well the retroreflective tape depicted the actual movements as humans. In addition to photographing and videotaping the uniforms, the researcher made photometric measurements under daytime and nighttime conditions and laboratory colormetric measurements of each type uniform. The report concludes that fluorescent colors enhance the daytime conspicuity of highway worker's clothing. The literature indicates that fluorescent orange and fluorescent strong yellow-green are the two best colors for use on high-visibility clothing. Of the garments studied in the daytime portion of

The Virginia Department of Transportation built a high-performance concrete (HPC) bridge with high-strength and low-permeability concrete in Richlands. The beams had a minimum compressive strength of 69 MPa (10,000 psi) at 28 days and large, 15 mm (0.6 in.) in diameter, strands at a 51-mm (2-in.) spacing. The deck concrete was designed to have a minimum compressive strength of 41 MPa (6,000 psi) and low permeability. This report describes the development of the HPC mixes, material and structural testing, construction, and condition assessment of the bridge after two winters. Structural testing was conducted on two full-scale 9.6-m (31-ft) AASHTO Type II beams with the large-diameter strands and with composite slabs. Pullout tests were conducted on the same strands as used in the beams. Tests were also conducted to determine if there were any residual phosphates on the strands as these have been suspected to adversely affect the bond between the strand and the hardened concrete. The test program, field application, and in-service performance of the bridge indicated that HPC concrete with high strength and low permeability can be produced using locally available material. The use of the large-diameter strands at a 51-mm (2-in.) spacing was also successful.

Stainless steel-clad rebar provides an opportunity to significantly increase the Cl- threshold concentration associated with active corrosion initiation compared to plain carbon steel. However, threshold Cl- concentrations for 316L stainless steel-clad rebar are unknown. Moreover, the impact of possible galvanic corrosion between the clad layer and any exposed carbon steel core has not been investigated. The Cl- threshold concentrations for corrosion initiation on clad 316L stainless steel (with a thickness of about 1 mm over a carbon steel core), solid 316LN stainless steel, and plain carbon steel were examined in saturated Ca(OH)2 plus various concentrations of NaCl. The electrochemical properties of "intact" 316L stainless steel-clad rebar were found to be similar to those of solid 316LN stainless steel according to several electrochemical criteria. The Cl- threshold concentrations for corrosion initiation were increased to Cl-/OH- molar ratios as high as 17 to 24 even at high anodic potentials for "intact" 316L-clad and solid 316LN stainless steel, respectively. Thus, active corrosion of "intact" 316L-clad rebar could be delayed for many years due to the high Cl-/OH- molar ratios required at the stainless steel/concrete interface and the slow transport rate of chloride in concrete. In contrast, the threshold chloride concentration for corrosion initiation on carbon steel was low (Cl-/OH- molar ratio < 1.5) at all potentials. Cladding with a physical breech exhibited Cl-/OH- thresholds dominated by the exposed plain carbon steel. Galvanic coupling between exposed plain carbon steel and the stainless steel-cladding accelerated corrosion of the plain carbon steel only at and above the Cl-/OH- ratio necessary for corrosion initiation on carbon steel.

Many urban transit providers are faced with the problem of declining ridership on traditional fixed route services in low density suburban areas. As a result, many fixed route services in such areas are not economically viable for the transit provider. Ridership levels on such routes could be increased by adding more flexibility to the fixed route structure by replacing the fixed route with a route deviation service. Another reason transit providers are turning to route deviation is because the 1990 Americans with Disabilities Act (ADA) required that certain disabled persons receive complementary paratransit services at a nominal cost. This meant that public transportation providers were suddenly faced with the challenge of providing traditional fixed-route transit service while also serving individuals with disabilities. As a result of these issues, research was conducted to demonstrate the technical feasibility of operating a route deviation bus service in a suburban area. The Peninsula Transportation District Commission (Pentran) provided a case study setting. The objectives of the research were to develop a decision support system (DSS) for route deviation services that will operate within a geographic information system (GIS) and to investigate route deviation design parameters. Such a DSS was developed and tested using two of Pentran's 13 routes. The results of the study are promising and demonstrate the technical feasibility of providing route deviation service under certain conditions. The prototype DSS can be used as the foundation for developing a full-fledged route deviation scheduling software that Pentran can use to implement such a service.

91023, This study developed traffic inputs for use with the Guide for the Mechanistic-Empirical Design of New & Rehabilitated Pavement Structures (MEPDG) in Virginia and sought to determine if the predicted distresses showed differences between site-specific and default traffic inputs for flexible and rigid pavements. The axle-load spectra, monthly adjustment factors, vehicle class distribution factors, and number of axles per truck inputs were considered. The predicted distresses based on site-specific traffic inputs from eight interstate and seven primary route weigh-in-motion sites in Virginia were compared to predicted distresses using MEPDG default traffic inputs. These comparisons were performed by use of a normalized difference statistic for each site-specific traffic input and the coefficient of variation for each pavement distress model. In addition, the practical significance for flexible pavements was considered from the difference in the predicted time to failure between site-specific and default traffic inputs. The analysis showed that the effect of the site-specific traffic inputs was generally not statistically significant when the uncertainty of the distress models was considered. However, the site-specific axle-load spectra and vehicle class distribution inputs showed a statistically significant effect on certain predicted distresses for flexible and rigid pavements, respectively. The study recommends that site-specific axle-load spectra data be considered for analysis of flexible pavements. Alternatively, summary (statewide average) axle-load spectra data for analysis of interstate and primary flexible pavements should be considered preferentially over default axle-load spectra. Site-specific vehicle class distribution factors should be considered for analysis of rigid pavements on the interstate system. Alternatively, summary (statewide average) vehicle class distribution factors for analysis of interstate rigid pavements should be considered preferentia

Problems with water penetrating into pavement were observed with the early coarse asphalt Superpave mixtures. There was justified concern that water would cause early deterioration; therefore, an effort was made to investigate the permeability problem and correct it. After an initial investigation revealed excessive permeability in many newly constructed Superpave pavements, the Virginia Department of Transportation's (VDOT) Materials Division decided that the potential permeability of mixtures should be determined during the mixture design phase prior to the start of construction. A technique of performing regressions of air voids and permeability with specimens prepared and tested in the laboratory was developed and refined at the Virginia Transportation Research Council. This investigation examined how well different labs agreed in two phases: one in which two VDOT laboratories participated and one in which contractors and VDOT laboratories participated. There was general agreement between laboratories in determining the acceptability of field samples of mixtures with regard to permeability. Potential difficulties and solutions in specimen preparation and regression analysis were discussed. The technique is currently being implemented by VDOT as a mixture design tool. It is estimated that the elimination of permeable mixtures that are not durable will save VDOT as much as $350,000 annually.

Senate Joint Resolution No. 7 (SJR-7) directs the Department to, develop a plan for reducing expenditures for administration and maintenance, by 5% as compared to FY 1987-88 appropriations and to continue, these reductions into the future. The plan is to achieve these purposes, through improved efficiency and productivity in Department operations., In addition, the Department is requested to compare the costs of maintenance, and other major nonconstruction activities with comparable activities, of other states; examine bidding procedures, procurement policies, and the process of obtaining rights-of-way; examine ways to accelerate, the road building process; consider the most appropriate cost ceiling on, projects to be built by state forces, and make recommendations to the, 1987 regular session of the General Assembly regarding these, considerations., This report responds to SJR-7, provides a status of the current, innovative environment in the Department, focuses on productivity, improvement plans to cut unit costs, and describes processes and programs, the Department has instituted or intends to institute that will, foster a continuing effort of improvements in productivity over the long, term.

The Commonwealth of Virginia is committed to comprehensive planning for all transportation modes. The development of transportation plans and funding programs is an integral component of the functions of many state, regional, and local agencies. The Statewide Intermodal Long-Range Transportation Policy Plan supports the planning efforts, policy making activities, and programming of projects for the various agencies and organizations involved in transportation planning. The intermodal transportation plan is especially beneficial in Virginia because the Commonwealth is a coastal state with a major international port, has broad areas that are densely populated and serves as a primary corridor for north-south and east-west freight and passenger transport. In addition, Virginia's transportation network serves the strategic interests of the nation's capital and serves the large number of military facilities located in the state. The primary purpose of this Statewide Intermodal Long-Range Transportation Policy Plan is to establish policy goals, which will guide Virginia's efforts to develop an efficient intermodal transportation system for the future.

The Virginia Transportation Research Council has been collecting safety belt use data in Virginia since 1974. In 1992, the National Highway Traffic Safety Administration (NHTSA) published the final guidelines for conducting surveys of belt and helmet use in the states. As of the 1992 survey, Virginia adopted the NHTSA protocol for its statewide survey. The results showed that Virginia's summer 2006 safety belt use rate was 78.7 percent and its motorcycle helmet use rate was 99.1 percent. In the 14 previous surveys, virtually all of the motorcycle drivers and passengers observed were using a helmet. For passenger car drivers and right front passengers observed from 1992 through 2005, use rates varied from a low of 67.1 percent in 1997 to a high of 80.4 percent in the summer of 2005. The summer 2006 use rate was 1.7 percent lower than the rate for summer 2005. It should be noted, however, that any differences between annual use rates might be attributable to differences in travel patterns or other extraneous variables, such as increases in gas prices and the resulting reduction in pleasure trips, rather than solely to changes in driver and occupant behavior.

Effective determination of long-term prestress losses is important in the design of prestressed concrete bridges. Over-predicting prestress losses results in an overly conservative design for service load stresses, and under-predicting prestress losses, can result in cracking at service loads. Creep and shrinkage produce the most significant time-dependent effect on prestress losses, and research has shown that high performance and high strength concretes (HPC and HSC) exhibit less creep and shrinkage than conventional concrete. For this reason, the majority of traditional creep and shrinkage models and methods for estimating prestress losses, over-predict the prestress losses of HPC and HSC girders. Nine HPC girders, with design compressive strengths ranging from 8,000 psi to 10,000 psi, and three 8,000 psi lightweight HPC (HPLWC) girders were instrumented to determine the changes in strain and prestress losses. Several creep and shrinkage models were used to model the instrumented girders. For the HPLWC, each model over-predicted the long-term strains, and the Shams and Kahn model was the best predictor of the measured strains. For the normal weight HPC, the models under-estimated the measured strains at early ages and over-estimated the measured strains at later ages, and the B3 model was the best-predictor of the measured strains. The PCI-BDM model was the most consistent model across all of the instrumented girders. Several methods for estimating prestress losses were also investigated. The methods correlated to high strength concrete, the PCI-BDM and NCHRP 496 methods, predicted the total losses more accurately than the methods provided in the AASHTO Specifications. The newer methods over-predicted the total losses of the HPLWC girders by no more than 8 ksi, and although they under-predicted the total losses of the normal weight HPC girders, they did so by less than 5 ksi.

The rapid increase in animal-vehicle collisions on U.S. roadways is a growing concern in terms of human safety, property damage and injury costs, and viability of wildlife populations. Wildlife crossing structures are gaining national recognition by transportation agencies as effective measures to reduce animal-vehicle collisions and connect wildlife habitats across transportation corridors. In Virginia, white-tailed deer and black bear pose the highest risk. This 1-year study was conducted to monitor various underpass structures in Virginia to determine the structural and location attributes that make a crossing successful in terms of use by large mammals. The underpasses, most of which were not specifically designed as wildlife crossings, consist of box culverts and bridges of varying sizes. Remote cameras installed at seven underpass sites in Virginia have recorded more than 2,700 wildlife photographs and documented 1,107 white-tailed deer crossings in the most heavily used structures. Underpasses with a minimum height of 12 ft were successful at facilitating deer passage. Such structures were also heavily used by a variety of wildlife species, including coyote, red fox, raccoon, groundhog, and opossum. Structures with drainages that mimic natural waterways can encourage use by a diversity of terrestrial, semi-aquatic, and aquatic species. This report provides guidance in choosing cost-effective underpass design and location features that are necessary to consider to increase motorist safety and habitat connectivity. The findings also demonstrate that if only a minimal number of deer-vehicle collisions is prevented by an effective underpass, the savings in property damage alone can outweigh the construction costs of the structure

Hydraulic cement concrete overlays are usually placed on bridges to reduce the infiltration of water and chloride ions and to improve skid resistance, ride quality, and surface appearance. Constructed in accordance with prescription specifications, some overlays have performed well for more than 30 years whereas others have cracked and delaminated before the overlay was opened to traffic. The use of performance specifications should increase the probability that concrete overlays will be constructed with high bond strengths and minimal cracks and will perform well for many years. The report describes the Virginia Department of Transportation's (VDOT) first experience with the use of a performance specification for the construction and acceptance of a high performance concrete overlay. Acceptance and payment were based on measurements for air content, compressive strength, permeability to chloride ion, and bond strength. Target air contents, high compressive strengths, low permeability, and good bond strengths were maintained throughout the project. Performance specifications with adjustments to the compensation specified in the contract likely influenced decisions made by the contractor and material supplier, and VDOT obtained a better product. VDOT should use the performance specification developed for this project for future bridge overlay projects.

Microscopic traffic simulation models have been widely accepted and applied in transportation engineering and planning practice for the past decades because simulation is cost-effective, safe, and fast. To achieve high fidelity and credibility for a traffic simulation model, calibration and validation are of utmost importance. Most calibration efforts reported in the literature have focused on the informal practice with a specific simulation model, but seldom did they propose a systematic procedure or guideline for simulation model calibration and validation. The purpose of this study was to develop and evaluate a procedure for microscopic simulation model calibration and validation. Three widely used microscopic traffic simulation models, VISSIM, PARAMICS, and CORSIM, were selected for model review and practice of model calibration and validation. The validity of the proposed procedure was evaluated and demonstrated via two case studies including an actuated signalized intersection and a 5-mile freeway segment with a lane-closure work zone. The simulation results were compared against the field data to determine the performance of the calibrated models. The proposed procedure yielded acceptable results for all applications, thus confirming that it was effective for the different networks and simulation models used in the study. Although the calibrated parameters generated the performance measures that were representative of the field conditions, the simulation results of the default parameters were significantly different from the field data.

The purpose of this report is to describe the cost of motor vehicle accidents in two ways first, by identifying the cost components and quantifying them, and second by showing the severity of such accidents in terms of human suffering. Although many statistics are kept concerning the causes of motor vehicle accidents, few are kept concerning the results. This report identifies techniques for estimating these statistics and points out the problems associated with each method. Alternative, and possibly more accurate, techniques are recommended for study. The report concludes that motor vehicle accidents cost the Commonwealth of Virginia over $800 million in 1980. Further, it shows that crashes are a leading cause of death for all Virginians, particularly for those younger than forty. Finally, it compares motor vehicle injuries with other accidental injuries, and it concludes that those caused by motor vehicles are, in general, significantly more severe.

This report represents efforts to design and evaluate a new sign design for emergency route trailblazing in a two-part series., Study was an off-road field experiment conducted to determine the best sign color combination, letter stroke width, and letter size for, the emergency sign. Based upon the results of that first study, three color combinations were chosen for testing (black on coral, black, on light blue, and yellow on purple) against a baseline color combination of black on orange. The test signs to be further tested, featured D series, 125-mm (5 in) height letters., Study 2 was conducted using an instrumented vehicle and survey questionnaire through a construction zone-related detour. The, independent variables of interest were sign color combination, age, and visibility condition. The findings of Study 2 indicated that use, of a color combination other than the traditional orange background with a black legend will improve driver performance and safety, when used for trailblazing during critical incidents., Based on the conclusions and other anecdotal evidence, the following recommendations were made, 1. Do not use a black on orange sign for trailblazing around a critical incident if an existing detour/construction zone is in place., 2. Do not use a black on coral sign for trailblazing around a critical incident., 3. A black on light blue sign is recommended due to its generally favorable subjective ratings and for minimization of the number of, turn errors made by drivers in an overlapping detour., 4. Despite recommendation 3, it is important to note that the black on light blue sign fades to take on the appearance of a regulatory, sign when headlights reflect onto it., 5. If the black on light blue sign is deemed inappropriate due to its appearance as a regulatory sign at night, consider using the yellow, on purple color combination. In this study, the yellow on purple sign color combination resulted in fewer turn errors than black, on orange and it was generally rated favorably by drivers, especially younger drivers.

This study evaluated existing traffic signal optimization programs including Synchro,TRANSYT-7F, and genetic algorithm optimization using real-world data collected in Virginia. As a first step, a microscopic simulation model, VISSIM, was extensively calibrated and validated using field data. Multiple simulation runs were then made for signal timing plans such that drivers' behavior, day-to-day traffic variation, etc. were considered in the evaluation. Finally, long-term demand growth or changes were statistically modeled and evaluated, again using multiple simulation runs. Five timing plans were evaluated using the simulation test bed. The timing plans under evaluation included (1) the former timing plan of the Virginia Department of Transportation(VDOT), (2) VDOT's current timing plan, (3) the genetic algorithm optimized timing plan, (4)the Synchro optimized timing plan, and (5) the TRANSYT-7F optimized timing plan. The simulation study results indicated that the current practice of VDOT's current signal optimization procedure significantly improved upon its former one by reducing travel times by 17% and total system delay by 36%. The three "optimized" timing plans did not provide significant improvements. Evaluation of the Lee-Jackson Memorial Highway network showed that the current VDOT signal optimization procedure significantly improved the performance of network operations. Thus, the study recommended that VDOT continue using its procedure for developing new timing plans but that it evaluate its signal timing plan regularly so that it does not become outdated.

The Virginia Department of Transportation is currently using the AASHTO Standard Specifications for Highway Bridges, with some modifications, for its seismic highway bridge design. In April 2001, the Recommended LRFD Guidelines for the Seismic Design of Highway Bridges were published. The influence of the LRFD Guidelines on Virginia bridges was investigated by analyzing two existing bridges. The first bridge has prestressed concrete girders and is located in the Richmond area. The second bridge has steel girders and is located in the Bristol area. Both bridges were two-span overpass structures with integral abutments. The bridges were analyzed using the methods prescribed in the guidelines. Then, the combined effects of the dead, live, and earthquake loads were compared to the strengths of the columns and the pier caps. The details of the bridge designs were also checked against the corresponding seismic design requirement. Results indicate that typical column spiral reinforcement is not adequate to satisfy the requirements of the new seismic guidelines. For the bridge in the Richmond area, spiral reinforcement was increased from a No. 5 at a 5-in pitch to a No. 5 at a 4-in pitch. For the bridge in Bristol, the increase was greater, from a No. 3 at 10.5 in to a No. 5 at 4 in. In addition to the increase in spiral reinforcement, other details, such as beam-column joint reinforcing and splice locations, require modifications. The calculated cost increases for the two bridges were 0.1 and 0.3 percent. An associated parametric study explored the effects on substructure design of different column heights, superstructure lengths, and soil classifications in different parts of Virginia. The study indicated that for bridges located on good soil (Class B), typical column longitudinal reinforcing ratios (about 1.5%) provide adequate strength to resist seismic forces. For bridges on poor soils (Class D) in regions of low to moderate seismic activity, column longitudinal reinfo

In 1990, the Virginia General Assembly established a commission to propose and enhance the economic development of the Southside region of the Commonwealth, the tier of largely rural counties across the southern border. The commission's 1991 report, House Document 42, included a recommendation for a timber bridge initiative to evaluate those structures as replacements for Virginia's structurally deficient bridges. The commission suggested that timber bridges might save highway construction funds and stimulate the forest products industry in Southside Virginia. Subsequently, the Virginia Department of Transportation developed a three-phase research effort that began with the construction of one bridge in each of the state's nine construction districts. This report, which concludes the formal stage of the initiative, addresses the costs, structural performance, and maintenance requirements to date for these structures. Although the performance of the study bridges has been acceptable, there is no indication that timber has been significantly accepted as a bridge construction material at this time. Timber bridges have not proven economically competitive from a first cost standpoint, and their life cycle cost competitiveness cannot be determined at this time. The economic viability of timber bridges is adversely affected by the lack of an industry presence in Virginia. This lack also casts doubt on the ability of the Virginia timber bridge initiative to enhance economic development in the Southside region of the Commonwealth.

This report describes an experimental investigation performed at live intersections to gather infrastructure-based naturalistic driver approach behavior data. This data was collected and analyzed with the goal of understanding how drivers approach intersections under various speeds and environmental conditions. Six stop-controlled intersection approaches across five intersections in the New River Valley, Virginia area were selected for data collection. The sites were selected based on the intersection characteristics and crash statistics. Data was collected from each site for at least two months resulting in over sixteen total months of data. A data acquisition system was devised and implemented to obtain the first intersection data set with fidelity sufficient for developing intersection collision avoidance threat assessment algorithms. An explorative analysis of driver stopping behavior and vehicle trajectories was also performed. Results indicate that an intersection collision system for stop-controlled intersections is feasible. Avenues for future research and potential uses of this new database are highlighted.

The Virginia Department of Transportation uses the Asphalt Pavement Analyzer with beam specimens to test and approve asphalt mixtures for rut resistance. Some agencies use cylindrical specimens that impart distinct testing advantages such as the ease of fabrication. This study attempted to develop a correlation between measurements using beams and cylindrical specimens. A secondary purpose was to locate and test mixes that had rutted in the field so that the precise laboratory criteria that define rutting could be determined. The tentative AASHTO procedure using cylindrical specimens with 4 percent air voids provided poor correlations with the conventional beam test results. A second testing using 8 percent air voids provided a better correlation, but the testing of cylindrical specimens was more variable than the testing of beam specimens. Therefore, the researchers recommended that VDOT continue testing beam specimens for approval and research. Correlations were developed that will allow the automated system of rut measurement to be used for future testing. VDOT pavements were found to develop negligible rutting, so the attempt to identify failed sections and ultimately failure criteria were not successful.

The transport properties of concrete are a primary element in determining the durability of concrete. In this study, several new test methods that directly measure aspects of fluid and ionic transport in concrete were examined. ASTM C 1543 and ASTM C 1556 provide the means for determining the apparent chloride diffusion coefficient, which is the controlling parameter for chloride ion migration in saturated pore systems. The chloride diffusion coefficient is an important input in service-life models for reinforced concrete. ASTM C 1585 measures the rate of absorption of water into the capillary pore system at a standard degree of saturation and thus provides a measure of fluid ingress and movement in concrete subject to drying conditions. These methods more accurately and completely describe the means of transport in concrete and should help improve the understanding and assessment of these important characteristics.

This study evaluated the bulb-T beams made with self-consolidating concrete (SCC) used in the Route 33 Bridge over the Pamunkey River at West Point, Virginia. Before the construction of the bridge, two test beams with SCC similar in cross section to the actual beams in the structure were cast and loaded to failure at the Federal Highway Administration's Turner-Fairbank Highway Research Center in McLean, Virginia. They were tested for transfer length, development length, flexural strength, and shear strength. These test beams demonstrated that SCC members can be designed using the same methods, assumptions, and limiting values as used for normally consolidated concrete beams. Based on the positive results, beams with SCC were cast and placed in the Route 33 Bridge. The study found that SCC yielding adequate slump flow can be prepared without segregation and with satisfactory strength and acceptably low permeability. However, proper attention must be devoted to mixture proportioning, workability, stability, and air content to ensure the quality of the product. The use of SCC in beams will have two major benefits: (1) expedited construction at the plant, a savings that is difficult to estimate at this time, and (2) improved quality. If the second benefit provides a 10 percent increase in service life, which is a reasonable expectation; given a typical $10.68 million yearly expenditure for prestressed concrete beams, this could lead to a cost savings for the Virginia Department of Transportation of close to $1 million per year.

82145, In the spring of 2007, the Virginia Department of Transportation (VDOT) began the process of reducing the number of superintendents and facilities dedicated to ordinary maintenance tasks. The need to downsize was the direct result of the requirement in House Bill 667 passed by the Virginia General Assembly in the 2006 session to outsource all normal interstate maintenance. The purpose of this study was to develop a procedure to assist VDOT in determining the number of superintendents needed to oversee and manage maintenance in each residency and the number of facilities needed to support their maintenance operations. Current superintendent (Transportation Operations Manager II)) workloads were quantified and calculated for each VDOT residency based on a limited number of workload parameters and a workload boundary representing the maximum observed workload for any combination of the parameters. Reductions in the number of superintendent positions were then made without exceeding the maximum current workloads for residencies. Deicing chemical storage capacity and maximum travel time to residency limits were determined to be the factors related to the number of necessary facilities. The minimum number of facilities to be retained by each residency was determined using residency-specific data related to these two factors. The procedure for determining the appropriate number of area headquarters superintendents and maintenance facilities was presented to and accepted by Virginia's Commonwealth Transportation Board in the fall of 2006. Reductions in the numbers of superintendent positions and facilities began taking place in the spring of 2007. Beginning with 213 superintendents at 207 maintenance area headquarters (AHQ) in 2006, the study presented in this report recommended a reduction of 35 superintendents, whereas the final plan issued by VDOT in 2007 called for a reduction of 32 superintendents. Similarly, the study presented here recommended a reduction of 35 AHQ f

Cement-treated aggregate (CTA) is commonly used to provide a stable base for pavements that are placed over weak soil subgrades. Because CTA reduces the thickness of the aggregate required to provide a durable base by approximately one-half, using it as a bearing layer for pavement can limit the quantity of unsuitable soil that must be excavated and removed, and can reduce the erodability of the stabilized soils. However, the field performance of CTA is variable, even when prepared according to set standards. This laboratory-based investigation explored the effects of fines content, cement content, mineralogy, and freeze/thaw cycling on the unconfined compressive strength of cement-treated aggregate. The mineralogy of the base aggregate was found to make a significant difference in the strength of the CTA, with strength increasing in the following order: mica, limestone, and diabase. The granite aggregate yielded variable results, but the strengths were generally on the order of those determined for the diabase aggregate. The pH of the samples also correlated well, with the measured strengths increasing as the pH increased. As was anticipated, increasing the cement content increased the measured unconfined compressive strength of cylinders that were not subjected to freeze/thaw cycling. The same basic trend was observed in cylinders that were subjected to freeze/thaw cycling; however, the increase was less pronounced in the cylinders that were subjected to physical abrasion during thaw cycles. The fines content did not significantly influence the unconfined compressive strength of the cylinders that were not subjected to freeze/thaw cycling; however, the fines content appeared to confer a protective effect to the durability of the cylinders that were subjected to freeze/thaw. For the freeze/thaw test conditions, the unconfined compressive strength increased as the fines content was increased.

For a number of land uses, published trip rates were not appropriate for application in West Virginia. There are a number of so-called special genertators, which are either unique to West Virginia (i.e., regional jails) or have assumed increased importanc;See also PB2000-105906 and PB2000-105907 (Volume 1). Sponsored by West Virginia Dept. of Transportation, Charleston. Div. of Highways. and Federal Highway Administration, Charleston, WV. West Virginia Div.;pg 224

Virginia Senate Bill 1279 (2003) calls for the creation of the Virginia Rail Transportation Development Authority. The purpose of this authority is "to finance or assist in the financing of the construction, repair, renovation, restoration, acquisition, and extension of rail lines, equipment, and facilities in the Commonwealth, including rolling stock, shops, terminals, bridges, tunnels, and any other passenger rail or freight rail facilities, equipment or infrastructure, upon a determination by the Authority that such action is in the public interest." Virginia Senate Joint Resolution 354 provided the argument for creating the new rail authority: (1) appropriate investments in railroad infrastructure will divert passenger and freight traffic from the highways to the railroads; (2) this will reduce the need for highway maintenance and construction, and it will reduce congestion, promote safety, and make it possible to avoid significant air and water pollution; (3) the railroads in Virginia do not have the financial resources to make the needed investments; thus, (4) a new rail authority is needed to finance or assist in the financing of the needed investments. The authors investigated rail authorities in other states in hopes of finding a model for the new rail authority. This survey did not provide any straightforward and unambiguous model for the "appropriate" structures and powers of the new authority. An examination of the Virginia Port Authority proved to be illuminating. It seems reasonable to attribute a significant part of the Virginia Port Authority's success to its "independence" from state government. Its "independence" allows it to function as a business with little interference from state government. The authors examined three options for satisfying the needs that were to be fulfilled by creating the new authority: (1) create an independent rail authority, (2) create a new rail agency within the government, or (3) provide the powers needed (such as bond

Lithium nitrate and lithium hyroxide were evaluated in the laboratory to examine their effectiveness in controlling expansions resulting from alkali-silica reaction and their effect on concrete properties. The lithium compounds were more effective in highly accelerated tests using Pyrex as the aggregate than in concrete prism tests using a reactive Virginia aggregate. The effective dosage of lithium nitrate in the concrete prism test was higher than that typically recommended. Lithium nitrate had a benign effect on the strength, electrical resistance, drying shrinkage, and resistance to freezing and thawing. Similar results were obtained with lithium hydroxide, with the exception of a retarding effect on strength development. Using current sources of fly ash and slag is more effective in addressing problems with ASR than using lithium admixtures.

This program provides for the initial pavement of rural roads. Under the Rural Rustic Roads Program, the governing body of any county, in consultation with the Department, may designate a road or road segment as a Rural Rustic Road provided such road or road segment (i) is located in a low-density development area and has an average daily traffic volume of at least 50 and 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 report discussed the result of the pilot program and the results of the first six roads paved under this program. Photographs, 18p.

This report presents the results of a project to develop a crawling robotics system for the remote visual inspection of high-mast light poles in Virginia. The first priority of this study was to develop a simple robotics application that would reduce hazards to the public and employees of the 'Virginia Department of Transportation and increase the efficiency of inspections. The prototype crawling robotics system developed (POLECAT-I) consists of a magnetically attached crawler for vertical and horizontal scanning of the outside of poles with a remote visual inspection device. Laboratory and field tests evaluated the crawler's mechanical performance and video resolution. The robot can inspect flat, cylindrical , and tapered surfaces with a longitudinal taper of 12 mm/m and a minimum outside diameter of200 mm; change the direction of the inspection from vertical to horizontal and vice versa on these surfaces; and overcome vertical obstacles up to 7 mm high. The system provides better crack resolution than conventional methods. This work holds great potential for significant cost savings with regard to inspections as well as improved safety.

This study evaluated the effects of temperature on the strength and permeability of concretes containing pozzolans (fly ash and silica fume) and slag. Two test programs were conducted. In the first, one control and five experimental mixtures containing silica fume, fly ash, or slag were evaluated. In the second, one control and three experimental mixtures containing fly ash or slag at a higher water-cementitious material ratio (W/CM) than used in the first program were evaluated. Concretes cured at higher temperatures had higher strengths up to 28 days but lower strengths at 1 year. Permeability decreased with time. Increasing early curing temperatures enabled the achievement of lower long-term permeability for 6 months and beyond at 28 days. Concretes containing a pozzolan or slag had a lower long-term permeability than the control. Adding a pozzolan was more effective in reducing permeability than reducing the W/CM. At cold temperatures, if the specified properties are not achieved, the contractor should change the mix design and/or provide insulating blankets and/or external heat to ensure the desired product.

This research effort was developed to record and analyze the Virginia Department of Transportation (VDOT) bridge/structure inspection processes as an aid to modernizing and automating these inspection processes through the use of mobile personal computer (PC) devices such as Palm/PPCs and other wearable computing devices. The research was conducted using an informal conversational interview process coupled with direct observations to match the perceived processes with actual processes. Once the interviews and observations were completed, workflows were mapped and analyzed for operational bottlenecks and process improvement opportunities. The results of the mappings and a comprehensive literature review were used to analyze the existing work processes. New process transformation maps were created and overlaid on current mappings to complete a transformation model. Redundancies were observed in the reporting function, and bottlenecks were identified within the inspection management and inspection functions. The research also indicates that the inspection process is readily transformable from one that relies on marking up paper reports in the field and then returning to the office for semi-manual reporting to one that is electronically assisted in areas of data capture, automated bridge inventory updates, and semi-automated report production. From this analysis a series of strategies and recommendations were made to assist VDOT in modernizing and transforming their current bridge inspection processes to more efficient digitally assisted processes.

In 2004, the Virginia Department of Transportation (VDOT) began examining the effects of allowing a 2-inch drop-off, rather than the specified 1.5-inch drop-off, between adjacent lanes. VDOT implemented a pilot program in its Northern Virginia District that gave paving contractors the option of not squaring up at the end of each shift on limited access roadways. This type of operation allowed the contractor to leave a milled section open to the traveling public and also to place an overlay in one lane but not the adjacent lane. The maximum allowable drop-off of the pavement in these instances was 2 inches. The purpose of this study was twofold. The first was to develop a functional performance specification for the milled surface exposed to traffic during paving operations on limited access roadways. This was done by measuring the milled surfaces on the roadways in the VDOT pilot program. The practices of other states regarding edge drop-offs were also investigated. The second and more important purpose was to investigate specific factors affecting paving and milling operations: safety, quality, productivity, and efficiency. The safety issues addressed included the effects of drop-offs created by milling or a straight overlay, loose debris created by raveling and "scabbing," windshield damage and accidents, and lane closure exposure time of the milling and paving crews. The condition of the milled surface was investigated to determine quality. To determine productivity and efficiency, three operations were investigated and compared: performance planing, mill and fill, and straight overlays. These investigations were conducted on particular limited access roadways in VDOT's Northern Virginia, Fredericksburg, and Salem districts. The results were as follows: 1.) The sand patch test was adopted to calculate the mean texture depth of milled surfaces, and a maximum average mean texture depth of 2 millimeters was validated for milled surfaces exposed to traffic on limited

A survey of the state of practice for designing slope erosion control measures within VDOT's nine districts has been conducted. On the basis of the survey, it is clear that there are no specific design procedures currently in use within VDOT for dealing with slope erosion. VDOT designers generally try to limit erosion by diverting runoff from adjacent areas, controlling concentrated flows on slopes, and establishing vegetation on slopes as quickly as possible. In addition, the Federal Highway Administration (FHWA) and the Departments of Transportation in states surrounding Virginia (Maryland, West Virginia, Kentucky, Tennessee, and North Carolina) were contacted. The state of practice for the FHWA and for these states appears to be similar to that used by VDOT. A review of the literature for soil erosion was performed. The universal soil loss equation (USLE), an empirical equation developed by the U.S. Department of Agriculture, was found to provide the best available quantitative tool for evaluating factors controlling the erosion process and determining what level of protection is appropriate. The authors recommend that the USLE be used to supplement VDOT's current principle-based design practices.

106469, Construction of a Virginia Department of Transportation project to install an Active Traffic Management (ATM) system on Interstate-66 (I-66) from U.S. 29 in Centreville to the Capital Beltway (I-495) was completed in September 2015. The project was constructed to improve safety and operations on I-66 through better management of existing roadway capacity. The main components of the ATM system were advisory variable speed limits (AVSL), queue warning systems (QWS), lane use control signs (LUCS), and hard shoulder running (HSR). Since ATM is still a relatively new approach in the United States, there was a need to analyze the effects of the I-66 ATM. Thus, a before-and-after study was conducted to quantify its effectiveness. The study used “after” data from October 2015-February 2016 (21 weeks) for the operations analysis and data from October 2015-December 2015 (13 weeks) for the safety analysis. Operations and safety evaluations were performed using limited data, so the results should be considered preliminary. The operational measures of effectiveness (MOEs) included ATM utilization rate, average travel time, travel time reliability, and total travel time delay. The safety MOEs included crash rates by type and severity and incident frequency. These MOEs were analyzed using INRIX travel time data, limited traffic volume point sensor data, police crash reports, and iPeMS traffic incident data. Segment-level analysis was performed to determine the segments that benefitted the most from ATM implementation. From this segment-level analysis, it was determined that HSR was the ATM component that led to most of the improvements on I-66. The results of the study indicate that the ATM produced positive operational and safety benefits across multiple MOEs. The ATM generally had limited operational and safety impacts during the weekday peak periods and some impacts during the midday and off-peak weekday periods. Average weekday travel times during the midday period in the off