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Abstract XIX

Structural Rehabilitation

Quality and Monitoring of Structural Rehabilitation Measures, Part 2: Review and Assessment

This report provides a review of potential non-destructive testing (NDT) techniques for carbon-fiber reinforced polymer (CFRP) materials. Theoretical and practical aspects of each individual technique are discussed including information on equipment, portability, data storage, capabilities, and limitations. The report ranks the NDT methods based on their usefulness for composite-strengthened, concrete structures.

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Vegetation and Riprap

Roadway Applications of Vegetation and Riprap for Streambank Protection

Riprap is commonly used for roadway protection at streams. However, vegetation is generally not a component of such protection. Environmental impacts such as increased water temperature and decreased quality of stream habitat may result from the removal of riparian vegetation during riprap construction. Near waterways containing threatened or endangered species, regulatory agencies require that remedial measures be taken if riparian vegetation is removed.
 
This study considered issues and options for streambank protection. An overview and analysis of the literature is provided. Roles for vegetation as part of streambank protection are considered. Techniques are given for use of vegetation with riprap and potential project opportunities are described. A comprehensive list of suitable species for streamside stabilization and riparian enhancement is included.


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Precast Concrete Barrier

Precast Concrete Barrier Crash Testing
The objectives of this project were to crash test the Oregon Standard (32-inch) F-shape precast concrete barrier and the Oregon Tall (42-inch) F-shape precast concrete barrier against the new NCHRP Report 350 standards, to ensure compliance of these safety systems. FHWA has required that such systems are acceptable under NCHRP standards by no later than October 2002. The results of the Test Level 3 crash tests showed that both barriers meet NCHRP requirements. Furthermore, FHWA acknowledged both barriers as having the best performance of any free-standing precast concrete barriers to date. The research report also discusses the performance of the Tall F-shape barrier in a Test Level 4 crash test, involving an 8,000 kg single-unit truck. The barrier passed this test as well. 
 


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Motor Fuel Tax

Alternatives to the Motor Fuel Tax

The National Highway Cooperative Research Program (NCHRP) published its Report 377, Alternatives to Motor Fuel Taxes for Financing Surface Transportation Improvements, in 1995. Increased fuel efficiency and the use of alternative fuels were seen as potential threats to future road finance due to the heavy reliance on fuel taxes. Much has happened since 1995. Technological progress in vehicle fuel-efficiency, alternative fuel vehicles, and methods of collecting alternative types of revenue, has been substantial. This research project focused on updating the work of NCHRP Report 377 to better evaluate the potential for alternatives to motor fuel taxes. The project maintained a primary focus on passenger vehicles and on the issues that must be addressed in designing an alternative. The project consisted of a literature review, an analysis of the economic issues related to fuel tax alternatives, and an analysis of the technological issues related to fuel tax alternatives. Several conclusions and recommendations for further research are offered. In addition, the report outlines several issues that policy makers will have to address as they explore alternatives to dependency on fuel tax revenue.



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Rockfall Catchment Area Design Guide (English and Metric)

Rockfall Catchment Area Design Guide (English and Metric)

The data gathered from an extensive research project consisting of rolling approximately 11,250 rocks off vertical; 0.25H:1V; 0.5H:1V; 0.75H:1V; and 1.0H:1.0V slopes of three different heights (40, 60 and 80 feet) into three differently inclined catchment areas (flat, 6H:1V and 4H:1V) has been used to develop design charts for dimensioning rockfall catchment areas adjacent to highways. A standard suite of 250 rocks was rolled for each slope and catchment area configuration tested. The standard suite included 100 rocks averaging 1 foot in diameter, 75 rocks averaging 2 feet in diameter and 75 rocks averaging 3 feet in diameter. The data was evaluated using statistical and graphical methods. The design charts are presented in a "practitioner-friendly" form that can be used to rapidly dimension rockfall catchment areas that satisfy specific rock catching/retention requirements. Based on cut slope angle and height and catchment area slope, the design charts estimate the catchment area widths required to retain percentages of rockfall ranging up to 99 percent.
 
Design guidelines and step-by-step design procedures are presented and illustrated with three worked example design problems. Seven actual highway project case study examples are also presented. They illustrate the practical application of the design procedure and design charts and/or use of site-specific rock rolling to aid in the rockfall mitigation design.
 
This report documents the test methods, the fieldwork performed, the data gathered, the means of analysis, the research results and sample application of the design charts. The data results in both tabular and graphical form are included in the Appendices. The Appendices also include the detailed project case study application examples.


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Monitoring of Structural Rehabilitation

Quality and Monitoring of Structural Rehabilitation Measures Part 1: Description of Potential Defect

Fiber reinforced polymer composites increasingly are being used to strengthen reinforced concrete structures. This interim report identifies defects that may occur with externally bonded composites on concrete. The report includes a description, sketch, and/or photograph of the different types of defects. A summary table organizes the defects according to initiation site, defect type, cause, and potential effect. Engineers and inspectors responsible for the quality and performance of composite-strengthened concrete structures will find the information valuable.

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Arrow Panel Displays

Evaluation of Arrow Panel Displays for Temporary Work Zones
The Oregon Department of Transportation evaluated the effectiveness of a "sequentially flashing diamond" arrow panel display as advance caution warning in temporary work zones.  This display was evaluated by comparing it with two others: the flashing line and flashing four-corner.  In survey responses from 33 state Departments of Transportation, each display was rated about the same in terms of effectiveness.
 
Field trials using each display were conducted in work zones set up on highway shoulders at two locations in Oregon.  Total evaluation time at each site was nine hours, divided into three, 3-hour test periods.  Each display operated for one hour during the 3-hour period.  Hourly average and 85th percentile speeds recorded during the tests were lower than corresponding hourly baseline speeds for all display modes.  The greatest speed reduction (from baseline) for most 3-hour periods occurred when the diamond display was operating.
 
Motorists were surveyed about the three displays.  People at a highway rest area were asked questions about the displays that were operating in the parking area.  Over 70% of 274 respondents chose the diamond display as the most effective at getting their attention.  However, 61% found the three displays confusing, particularly the line and the four-corner.  Although there was evidence of confusion about the displays, 80% of the respondents said they would like to see the diamond used when work is taking place on Oregon highways.
 
The results of the field trials and motorist survey show considerable potential for the diamond display's use as an advance warning device in temporary work zones.


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Desert Varnish Evaluation

Desert Varnish Rocky Point Viaduct
In 1995, ODOT sprayed the reinforced shotcrete slope stabilization project near Port Orford on US 101 with Permeon, a rock coloring material also called desert varnish.  The application colored the shotcrete to a weathered-looking dull brown, masking its gray-white concrete appearance.  Some weathering in the last three years has changed the color.  Water and mud running from the above cliff have added white and brown streaks.  Also, wind and salt air erosion have faded some of the coloring.  The test area is still darker than the control section which received no application.  
 
The value of the desert varnish appears to be marginal.  If the three-year trend continues, the salt air and strong winds will discolor the entire treatment.


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Analysis of Design Attributes

Analysis of Design Attributes and Crashes on the Oregon Highway System
This report has investigated the statistical relationship between crash activity and roadway design attributes on the Oregon state highway system. Crash models were estimated from highway segments distinguished by functional classification (freeway v. non-freeway) and location (urban v. non-urban). A number of design attributes were found to be statistically related to crash activity in the various models, including the number of lanes, curve characteristics, vertical grade, surface type, median type, turning lanes, shoulder width, and lane width. In selected instances, CRFs calculated from crash model results were compared to those presently used to evaluate projects in ODOT’s Safety Improvement Program.
 
The range of design attributes addressed in this study is similar to what has been covered by other studies reported in the crash modeling literature, and the results obtained for Oregon are generally consistent with those obtained from other study areas. Although relatively few at present, the number of design attributes included in crash models will likely grow over time as automated roadway inventory data become increasingly available. Nevertheless, it is doubtful that the coverage of crash models will ever be sufficiently comprehensive to effectively substitute for the present system, which encompasses hundreds of countermeasures in differing contexts.
 
While the number of highway design attributes specified in crash models is limited, they represent a relatively large share of the capital invested in safety improvements. Safety-related outlays for lane and shoulder widening, altering horizontal and vertical curves, introducing median treatments, and for resurfacing have very large cost implications compared to outlays for signage and markings. Cross-sectional crash models usually specify variables that represent countermeasures associated with the more costly outlays. Thus, the models provide states with an opportunity to validate the CRFs that are most important economically.


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Vegetated Riprap

The Role of Vegetated Riprap in Highway Applications
Riprap is the most commonly used material to protect bridge abutments and highway embankments adjacent to bridge abutments from erosion.  Removal of the riparian vegetation in preparation for riprap construction can lead to environmental impacts such as increased water temperature and reduction of the quality of stream habitat.  A method that is commonly recommended as a mitigation measure is to plant willows in the riprap to reestablish the riparian vegetation.  There are engineering concerns that the willows will reduce the stability and flexibility of the riprap and eventually cause the riprap to fail.  This report addresses the review of literature on the subject.

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Corvallis Case Study

Corvallis Case Study: Indirect Land Use and Growth Impacts on Highway Improvements
To improve environmental analysis of indirect land use impacts of highway capacity improvements, this study analyzed the land use and growth patterns of 20 Oregon communities over 20 years. Using a Geographic Information System and aerial photos, growth patterns were categorized and mapped. Factors related to land use and transportation were evaluated for their relationships to resulting growth patterns. These relationships were further investigated in six in-depth case studies of development prior to, during, and after construction of a highway capacity improvement.
 
A guidebook was produced to provide guidance to ODOT staff for completing environmental analysis and documentation on indirect land use impacts of highway improvements, based on the findings of the study. One finding was that most highway capacity increases do not cause development to be dramatically different from local land use plan guidance, or from what would have occurred in the absence of the highway improvement. In Oregon, local governments hold the tools to determine development patterns, using zoning and public utilities such as water, sewer and roads.
 
The guidebook is not a directive but a compilation of recommendations for a systematic look and consistent approach to predicting the indirect land use impacts of highway improvements. Appendices A-F of this report provide background on the study findings, including the literature review, growth trends analysis and six in-depth case studies. Also included in the appendices are a discussion of population and employment forecasting issues and a summary of ODOT processes for project evaluation. This report is the full case study report for one community – Corvallis.


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FRP Composite-Strengthened

Behavior of FRP Composite-Strengthened Beams Under Static and Cyclic Loading 
 Small, concrete beams with no steel reinforcement were externally strengthened with eight different configurations of fiber reinforced polymer composites.  The reinforcement configurations consisted of high and low modulus epoxy, high and low modulus fibers, and 1 and 2 composite layers.  Load capacity tests were conducted for all eight configurations, and fatigue tests were conducted for two of the configurations.  Beams with the higher modulus epoxy had more load capacity than beams with the lower modulus epoxy.  However, this enhancement decreased as the failure mode changed from flexural failure to less desirable failure modes.  The modulus of the resin had no effect on beam stiffness.  The fatigue strength of the beams was strongly dependent on the load capacity of the beams; consequently, higher modulus epoxy could improve the fatigue performance of concrete beams.

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Asphalt Concrete Patching - Interim Report

Asphalt Concrete Patching Material Evaluation - Interim Report

There are a great number of proprietary pothole patching products available on the market that claim to be the "perfect" fix to repair asphalt concrete highway potholes. These products are difficult to evaluate. Without actually placing the products in a test deck, it is difficult to determine the quality of a product by looking at the product literature.
 
The objective of this study was to evaluate new patching materials to determine their viability. Issues such as uniformity, availability, handling, stockpiling impacts, compatibility with common roadway materials, and field performance were investigated. A literature review of laboratory, field, and pothole patching material ranking was performed.
 
Both a laboratory and field verification component were included. The laboratory component included a series of material tests with pass-fail criteria. The field portion of the study included manufactured potholes and natural potholes. All fieldwork performed was done with standard maintenance procedures. Following placement, pothole test patches were monitored and will continue to be monitored for an additional year.

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LaGrande/Island City Study

LaGrande/Island City Case Study: Indirect Land Use and Growth Impacts of Highway Improvements

To improve environmental analysis of indirect land use impacts of highway capacity improvements, this study analyzed the land use and growth patterns of 20 Oregon communities over 20 years. Using a Geographic Information System and aerial photos, growth patterns were categorized and mapped. Factors related to land use and transportation were evaluated for their relationships to resulting growth patterns. These relationships were further investigated in six in-depth case studies of development prior to, during, and after construction of a highway capacity improvement.
 
A guidebook was produced to provide guidance to ODOT staff for completing environmental analysis and documentation on indirect land use impacts of highway improvements, based on the findings of the study. One finding was that most highway capacity increases do not cause development to be dramatically different from local land use plan guidance, or from what would have occurred in the absence of the highway improvement. In Oregon, local governments hold the tools to determine development patterns, using zoning and public utilities such as water, sewer and roads.
 
The guidebook is not a directive but a compilation of recommendations for a systematic look and consistent approach to predicting the indirect land use impacts of highway improvements. Appendices A-F of this report provide background on the study findings, including the literature review, growth trends analysis and six in-depth case studies. Also included in the appendices are a discussion of population and employment forecasting issues and a summary of ODOT processes for project evaluation. This report is the full case study report for one community – La Grande/Island City.

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Cementitious Materials

Cementitious Materials for Thin Patches
Ten cementitious patching materials, which were suitable for thin, vertical repairs according to the manufacturers, were evaluated. Compatibility with cathodic protection systems was a particular concern. The materials were tested for propensity to crack and delaminate, compressive strength, bond strength, length change, and resistivity. Three materials, ThoRoc SP20 Spray Mortar, Re-Crete 20, and Polyfast LPL had the best results; consequently, they are recommended for field trials.

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Finite Element Modeling

Finite Element Modeling of Concrete Structures Strengthened with FRP Laminates
Linear and non-linear finite element method models were developed for a reinforced concrete bridge that had been strengthened with fiber reinforced polymer (FRP) composites. ANSYS and SAP2000 modeling software were used; however, most of the development effort used ANSYS. The model results agreed well with measurements from full-size laboratory beams and the actual bridge. As expected, a comparison using model results showed that the structural behavior of the bridge before and after strengthening was nearly the same for legal loads. Guidelines for developing finite element models for reinforced concrete bridges were discussed.  
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Micro-Deval Aggregate Test

Micro-Deval Coarse Aggregate Test Evaluation
Studded tire use in Oregon results in millions of dollars of pavement damage annually. Accurate tests are needed to qualify durable aggregate for pavements to resist studded tire damage. ODOT currently uses the Los Angeles abrasion test as one of the tests to establish aggregate quality. The LA abrasion test may not adequately represent the aggregate durability. The Micro-Deval test was investigated to determine if it provided a better means of establishing aggregate quality for use in pavements.
 
During the summer of 1999, ODOT purchased a Micro-Deval abrasion tester to evaluate aggregate durability of known and new sources. Test results were compared with measured or inferred performance of known sources. Based on the results of the Micro-Deval testing, it does not appear that the equipment is any more discriminating with respect to aggregate abrasive resistance than the Los Angeles abrasion testing.
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Indirect Land Use

A Guidebook for Evaluating the Indirect Land Use and Growth Impacts of Highway Improvements
In 1998, the Oregon Department of Transportation undertook a study of the impacts of highway capacity improvements on land uses and growth, particularly at the urban fringe. The objective was to better understand the "cause and effect" relationships among highway capacity, travel demand and development patterns. A variety of factors to resulting growth were evaluated for their ability to predict growth. Case studies of six communities provided an in-depth understanding of the pressures which drive development decisions and land use change.
 
This guidebook provides guidance to ODOT staff for completing environmental analysis and documentation on indirect land use impacts of highway improvements, based on findings of the study. One finding was that most highway capacity increases do not cause development to be dramatically different from local land use plan guidance, or from what would have occurred in absence of the highway improvement. In Oregon, local governments hold the tools to determine development patterns, using zoning and public utilities such as water, sewer and roads.
 
This guidebook is not a directive, but a compilation of recommendations for a systematic look and consistent approach to predicting the indirect land use impacts of highway improvements. Appendices A-F of this report provide background on the study findings, including the literature review, growth trends analysis and six in-depth case studies. Also included in the appendices are a discussion of population and employment forecasting issues and a summary of ODOT processes for project evaluation.

Published as two documents: Final Report and Appendices
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