CTR Library's Research Digest --Oct 2010

Research Digest FORWARD ALL REQUESTS TO: The University of Texas at Austin Center for Transportation Research LIBRARY 1616 Guadalupe St. | Suite 4.202 | Austin, Texas 78701 Phones: (512) 232-3126 and (512) 232-3138 Email: ctrlib@austin.utexas.edu In this Issue:

National Cooperative Highway Research Program (NCHRP) Reports

Table of Contents Item 1.

Human Factors Guidelines for Road Systems. Collection C (NCHRP Report 600C)....... 1

Item 2.

Blast-Resistant Highway Bridges (NCHRP Report 645).......................................................1..

Item 3.

Validating the Fatigue Endurance Limit for Hot Mix Asphalt (NCHRP Report 646)..............

2

Item 4.

Recommended Design Specifications for Live Load Distribution to Buried Structures (NCHRP Report 647).......................................................................................................... 2

Item 5.

Mixing and Compaction Temperatures of Asphalt Binders in Hot-Mix Asphalt (NCHRP Report 648).......................................................................................................... 3

Item 6.

Separation of Vehicles (NCHRP Report 649 / NCFRP Report 3)..................................... 3

Item 7.

Median Intersection Design for Rural High-Speed Divided Highways (NCHRP Report 650)......................................................................................................................... 4

Item 8.

LRFD Design and Construction of Shallow Foundations for Highway Bridge Structures (NCHRP Report 651)........................................................................................ 4

Item 9.

Time-Related Incentive and Disincentive Provisions in Highway Construction Contracts (NCHRP Report 652)......................................................................................... 5

Item 10.

Effects of Debris on Bridge Pier Scour (NCHRP Report 653).......................................... 5

Item 11.

Evaluation and Repair Procedures for Precast/Prestressed Concrete Girders with Longitudinal Cracking in the Web (NCHRP Report 654)................................................. 5

Item 12.

Recommended Guide Specification for the Design of Externally Bonded FRP Systems for Repair and Strengthening of Concrete Bridge Elements (NCHRP Report 655).......... 6

Item 13.

Criteria for Restoration of Longitudinal Barriers (NCHRP Report 656)........................... 6

Item 14.

Guidebook for Implementing Passenger Rail Service on Shared Passenger and Freight Corridors (NCHRP Report 657)............................................................................ 7

Item 15.

Guidebook on Risk Analysis Tools and Management Practices to Control Transportation Project Cost (NCHRP Report 658)............................................................ 7

Item 16.

Guide for the Geometric Design of Driveways (NCHRP Report 659).............................. 8

Item 17.

Transportation Performance Management (NCHRP Report 660)..................................... 8

Item 18.

A Guidebook for Corridor-Based Statewide Transportation Planning (NCHRP Report 661)......................................................................................................................... 9

Item 19.

Accelerating Transportation Project and Program Delivery (NCHRP Report 662).......... 9

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Research and Technology Implementation Office

October 2010

Research Digest Item 1 Human Factors Guidelines for Road Systems. Collection C : Chapters 16-20, 22 Tutorials 4-6, 23 (Updated), 24-25, 26 (Updated) TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 600C • 2010 The TRB, AASHTO, and the FHWA have been working since 2001 on two projects that together will help to promote greater safety for all road users. These two projects are the "Highway Safety Manual" (HSM) and the "Human Factors Guidelines for Road Systems" (HFG). The HSM and HFG promote improved safety for highway users and complement each other. They should be used together. Neither document is a substitute for national or state standards such as AASHTO’s "A Policy on Geometric Design of Highways and Streets" or the "Manual on Uniform Traffic Control Devices."

NCHRP 600 explores human factors principles and findings for consideration by highway designers and traffic engineers. The report is designed to help the nonexpert in human factors to consider more effectively the roadway user's capabilities and limitations in the design and operation of highway facilities. The full Table of Contents can be found at http://144.171.11.40/news/blurb_detail.asp?id=8715. Additional chapters, to be developed under NCHRP Project 17-41 according to the priorities established by the project panel, are expected in late 2010.

NCHRP Report 600 Collection C supplements NCHRP Report 600A and 600B. It contains the following topics: Special Considerations for Rural Environments, Speed Perception, Speed Choice, and Speed Control; Signing; Changeable Message Signs; and Markings. It also includes new tutorials, references and updated index.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_600C.pdf

Item 2 Blast-Resistant Highway Bridges : Design and Detailing Guidelines TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 645 • 2010 The possibility of terrorism against our nation’s bridges is an ever-increasing threat in today’s society. Data collected by the Mineta Transportation Institute indicate that at least 53 terrorist attacks worldwide specifically targeted bridges between 1980 and 2006, and 60% of those attacks were bombings. Moreover, accidental collapses of bridges in the U.S. and terrorist attacks against bridges in Iraq illustrate the large economic and socioeconomic consequences of catastrophic bridge failures. To help ensure the safety of bridges in the U.S. and protect the nation’s infrastructure, there is a need for design and detailing guidelines for blast-resistant highway bridges.

To address this need, the National Cooperative Highway Research Program (NCHRP) funded NCHRP Project 1272 to investigate highway bridges subjected to explosive loads.

This report presents code-ready language containing general design guidance and a simplified design procedure for blast-resistant reinforced concrete bridge columns. The report also provides the results of experimental blast tests and analytical research on reinforced concrete bridge columns designed to investigate the effectiveness of a variety of different design techniques. The material in this report will be of immediate interest to bridge designers.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_645.pdf _____________________________________________________________________________________________

Research and Technology Implementation Office

October 2010

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Research Digest Item 3 Validating the Fatigue Endurance Limit for Hot Mix Asphalt TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 646 • 2010 Many well-constructed flexible pavements with a thick HMA structure have been in service for 40 or more years without any evidence of bottom-up fatigue cracking. This field experience suggests that an endurance limit, that is, a level of strain below which fatigue damage does not occur for any number of load repetitions, is a valid concept for HMA mixtures.

This report presents the findings of research performed to investigate the existence of a fatigue endurance limit for hot mix asphalt (HMA) mixtures, the effect of HMA mixture characteristics on the endurance limit, and the potential for the limit's incorporation in structural design methods for flexible pavements. The report describes the research performed and includes proposed standard practices using various experimental and analytical procedures for determining the endurance limit of HMA mixtures. Thus, the report will be of immediate interest to materials and structural design engineers in state highway agencies and engineers in the HMA construction industry.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_646.pdf

Item 4 Recommended Design Specifications for Live Load Distribution to Buried Structures TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 647 • 2010 TRB’s National Cooperative Highway Research Program (NCHRP) Report 647: Recommended Design Specifications for Live Load Distribution to Buried Structures explores recommendations to revise the American Association of State Highway and Transportation Officials Load and Resistance Factor Design Bridge Design Specifications relating to the distribution of live load to buried structures.

The report examines development of simplified design equations (SDEs) for structural response based on threedimensional (3D) analysis of 830 buried culverts. In addition, the report suggests guidelines for conducting twodimensional and 3D modeling for design situations with conditions not covered by the SDEs. Appendixes A through E for NCHRP Report 647 are only available on TRB's web site. These appendixes are as follows: Appendix A "3-D Numerical Analysis of Live Load Distribution: Soil Constitutive Models, Load Factoring and Comparison with Field Measurements;" Appendix B: "3-D Numerical Analysis of Live Load Distribution: Model Details and Results;" Appendix C "Recommended Revision to AASHTO LRFD Bridge Design Specifications;" Appendix D.1: "Parametric Study MathCAD Calculation Sheets;" Appendix D.2: "Tabular Listings of Parametric Study Results;" Appendix E: "Refined Analysis Guidelines."

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_647.pdf

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Research and Technology Implementation Office

October 2010

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Research Digest Item 5 Mixing and Compaction Temperatures of Asphalt Binders in Hot-Mix Asphalt TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 648 • 2010 The Asphalt Institute (AI) procedure for determining mixing and compaction temperatures of asphalt binders was developed for penetration- and viscosity-graded asphalt cements used in the United States until the 1990s. Since that time, the use of modified, performance-graded asphalt binders in HMA paving has increased significantly, especially on high-volume traffic routes. The AI procedure often requires heating of modified binders to unrealistically high temperatures that can potentially damage the asphalt binder. To overcome this problem, highway agencies usually rely on the modifier suppliers to recommend mixing and compaction temperatures, a circumstance that can produce mixed results.

The objective of this research was to identify or develop a simple, rapid, and accurate laboratory procedure suitable for routine use for determining the mixing and compaction temperatures of both unmodified and modified asphalt binder. The research was performed by the National Center for Asphalt Technology, Auburn University, Auburn, Alabama with the support of Malvern Instruments Inc., Westborough, Massachusetts.

In the course of the research, the project team evaluated existing and emerging methods to determine temperatures that will provide satisfactory aggregate coating during laboratory mixing and appropriate laboratory specimen compaction without degrading the asphalt binder and identified two improved, equally effective test methods.

These tests, termed (1) the phase angle method and (2) the steady shear flow viscosity (SSFV) method, provide reasonable, consistent mixing and compaction temperatures that correlate well with the results of HMA coating, workability, and compactability tests for both binder types. The phase angle and SSFV measurements are made with the dynamic shear rheometer (DSR), already widely used in asphalt laboratories for measuring binder stiffness over a range of temperatures and frequencies.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_648.pdf

Item 6 Separation of Vehicles : CMV-Only Lanes TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 649 / NCFRP Report 3 • 2010 This report presents an extensive compendium of information about commercial motor vehicle-only (CMV-only) lanes and examines major issues and concepts that should be understood in developing new applications of CMVonly lane concepts as a potential method for both easing congestion and reducing the number traffic accidents on highways. Appendices to this report, including an annotated literature review, performance evaluation criteria, benefits monetization factors and unit costs, and net present value calculations for benefit-cost analysis, are available on the TRB website. This report and supplemental information can be used by public agencies that may be considering CMV-only lane concepts in corridor studies or other planning applications. This report provides data such agencies can use to support their own evaluations of CMV-only lane projects.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/ncfrp/ncfrp_rpt_003.pdf

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Research and Technology Implementation Office

October 2010

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Research Digest Item 7 Median Intersection Design for Rural High-Speed Divided Highways TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 650 • 2010 As a result of the trend to convert rural two-lane roadways into multilane divided highways, rural expressways are a rapidly growing component of the nation’s transportation network. As these facilities experience growth in traffic, at-grade intersection collisions begin to reduce the safety benefits that should be achieved as a result of conversion, bringing into question the assumption that expressways are an effective alternative to full accesscontrolled facilities at high volumes. When the safety performance of at-grade intersections begins to deteriorate, the traditional approach taken by STAs is to consider improvements one intersection at a time.

This report describes common safety issues at median intersections on rural divided highways and presents innovative geometric and operational treatments for addressing those issues. Ten case studies illustrate how they have been applied in the field. The report includes recommendations for modifications to the AASHTO A Policy on Geometric Design of Highways and Streets (Green Book) and the Manual on Uniform Traffic Control Devices (MUTCD).

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_650.pdf

Item 8 LRFD Design and Construction of Shallow Foundations for Highway Bridge Structures TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 651 • 2010 Shallow foundations are used for a large percentage of bridges, retaining walls, and other transportation structures. Reliability-based resistance factors are needed to incorporate into design specifications for use by transportation agencies. LRFD design specifications for shallow foundations of highway structures need to be developed using a reliability-based calibration procedure, consistent with the calibration of load and resistance factors for bridge superstructures. Load and resistance factors should account for uncertainties related to load combinations, site conditions, soil and rock type and properties, and methods of testing and analysis. It is believed that resistance factors for shallow foundations in Section 10 of the current AASHTO LRFD Bridge Design Specifications do not satisfy these requirements.

The objective of this project was to develop recommended changes to Section 10 of the AASHTO LRFD Bridge Design Specifications for the strength limit state design of shallow foundations. The report fully documents the research leading to the recommended design specifications for the strength limit state design of shallow foundations.

Appendixes A through H from the research agency's final report are not published herein but are available on the TRB website (www.trb.org) by searching on "NCHRP Report 651". These appendixes are titled as follows: Appendix A: "Alternative Model Background;" Appendix B: "Findings: State of Practice, Serviceability and Databases;" Appendix C: Questionnaire Summary; Appendix D: UML-GTR ShalFound07 Database; Appendix E: UML-GTR RockFound07 Database; Appendix F: "Shallow Foundations Modes of Failure and Failure Criteria;" Appendix G: Bias Calculation Examples; Appendix H: Design Examples.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_651.pdf _____________________________________________________________________________________________

Research and Technology Implementation Office

October 2010

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Research Digest Item 9 Time-Related Incentive and Disincentive Provisions in Highway Construction Contracts TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 652 • 2010 This report explores best practices of time-related incentive and disincentive contract provisions and their effect on staffing levels, productivity, project cost, quality, contract administration, and the contractor’s operations and innovations. The report also examines a decision process guide as a potential template for crafting the incentive and disincentive provisions in a highway construction contract.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_652.pdf

Item 10 Effects of Debris on Bridge Pier Scour TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 653 • 2010 This report provides guidelines for practitioners to estimate the quantity of accumulated, flow event debris, based on the density and type of woody vegetation and river bank condition upstream and analytical procedures to quantify the effects of resulting debris-induced scour on bridge piers. The report should be of interest to bridge engineers, maintenance personnel and operations staff at state and local agencies.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_653.pdf

Item 11 Evaluation and Repair Procedures for Precast/Prestressed Concrete Girders with Longitudinal Cracking in the Web TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 654 • 2010 This report explores the acceptance, repair, or rejection of precast/prestressed concrete girders with longitudinal web cracking. The report also examines suggested revisions to the American Association of State Highway and Transportation Officials’ Load Resistance Factor Design Bridge Design Specifications and measures to develop improved crack control reinforcement details for use in new girders.

Appendices A through G from the research agency's final report are not published herein but are available on the TRB website. These appendixes are as follows: Appendix A: Literature Review; Appendix B: National Survey; Appendix C: Structural Investigation & Full-Scale Girder Testing; Appendix D; Sealant Specifications; Appendix E: ASTM Specifications; Appendix F: Field Inspection of Bridges; Appendix G: Design Examples of End Zone Reinforcement Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_654.pdf _____________________________________________________________________________________________

Research and Technology Implementation Office

October 2010

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Research Digest Item 12 Recommended Guide Specification for the Design of Externally Bonded FRP Systems for Repair and Strengthening of Concrete Bridge Elements TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 655 • 2010 This report presents a recommended guide specification for the design of externally bonded Fiber-Reinforced Polymer (FRP) systems for the repair and strengthening of concrete bridge elements. This guide specification addresses the design requirements for members subjected to different loading conditions (e.g., flexure, shear and torsion, and combined axial force and flexure).

The guide specification is supplemented by design examples to illustrate its use for different FRP strengthening applications. The guide specification is presented in AASHTO LRFD format to facilitate use and incorporation into the AASHTO LRFD Bridge Design Specification.

The material contained in the report should be of immediate interest to state engineers and others involved in the strengthening and repair of concrete structures using FRP composites.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_655.pdf

Item 13 Criteria for Restoration of Longitudinal Barriers TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 656 • 2010 Longitudinal barriers, such as guardrails, are installed along a roadway or in the roadway median to prevent an errant vehicle from traversing a steep slope, impacting a more dangerous roadside object, or entering opposing vehicle travel lanes. Full scale crash testing is used to evaluate the performance of these barriers prior to their installation along a highway (Ray and McGinnis, 1997; Ross et al, 1993). Based on an evaluation using real-world crash data, these barriers have consistently been shown to be effective (Short and Robertson, 1998; Michie and Bronstad, 1994; Elvik, 1995). Very little is known, however, with respect to how these barriers perform after they have been damaged.

This report provides guidance to assist maintenance personnel in identifying levels of damage and deterioration to longitudinal barriers that require repairs to restore operational performance. Using pendulum testing, full-scale crash testing, and finite element simulations, the research team developed a “Field Guide for Criteria for Restoration of Longitudinal Barriers.”

The report will be of particular interest to maintenance personnel responsible for the maintenance and repair of damaged longitudinal barriers.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_656.pdf

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Research and Technology Implementation Office

October 2010

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Research Digest Item 14 Guidebook for Implementing Passenger Rail Service on Shared Passenger and Freight Corridors TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 657 • 2010 The United States is experiencing increasing congestion on the nation’s highways, as well as capacity constraints on the national rail system. Higher gasoline prices and concerns about greenhouse gas emissions are increasing public demand for energy-efficient transportation alternatives. Faced with these challenges and increased emphasis on multi-modal planning under federal transportation statutes (i.e., ISTEA, TEA-21, and SAFETEALU), state interest in intercity passenger and commuter rail development has grown significantly in recent years.

This Guidebook will aid states in developing public-private partnerships with private freight railroads to permit operation of passenger services over shared-use rail corridors. The Guidebook should encourage the broad acceptance of improved principles, processes, and methods to support agreements on access, allocation of operation and maintenance costs, capacity allocation, operational issues, future responsibilities for infrastructure improvements, and other fundamental issues that will affect the ultimate success of shared-use passenger and freight agreements between public and private railroad stakeholders.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_657.pdf

Item 15 Guidebook on Risk Analysis Tools and Management Practices to Control Transportation Project Cost TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 658 • 2010 Project cost escalation is a serious problem facing state highway agencies (SHAs). The failure to deliver individual projects and programs within established budgets has a detrimental effect on later programs and causes a loss of faith in the agency’s ability to wisely use the public’s money. Highway design and construction projects can be extremely complex and are often fraught with uncertainty. However, engineers, project managers, and cost estimators often overlook or fail to recognize project uncertainty early in the project development process. As a result they do not communicate uncertainty and its effect to the stakeholders. A comprehensive risk management approach can help project teams identify, assess, mitigate, and control project risks. Among the benefits of a comprehensive risk management approach is the ability to generate range estimates early in the project development process and to establish justifiable contingencies that can be resolved throughout the design and construction process.

This guidebook presents a systematic process to apply risk analysis tools and management practices to aid SHA management in controlling project cost growth. The Guidebook addresses risk identification, assessment, analysis, mitigation, allocation, and tracking and control in a manner that is systematically integrated into the organizational structure and culture of SHAs. Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_658.pdf

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Research and Technology Implementation Office

October 2010

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Research Digest Item 16 Guide for the Geometric Design of Driveways TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 659 • 2010 This report explores guidelines related to the geometric design of driveways. The report includes driveway-related terms and definitions, an examination of basic geometric controls, a summary of access spacing principles, and detailed discussions of various geometric design elements. This publication complements documents such as the AASHTO Policy on the Geometric Design of Streets and Highways (1-1) and the Access Management Manual (12). This guide is intended for use in both the public and private sectors.

Material related to and supporting the contents of NCHRP Report 659, including an extensive review of literature, has been published as NCHRP Web-Only Document 151: Geometric Design of Driveways which is available at http://www.trb.org/Publications/Blurbs/163869.aspx Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_659.pdf

Item 17 Transportation Performance Management : Insight from Practitioners TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 660 • 2010 This guidebook provides insights from selected transportation agencies who are successfully integrating transportation performance management programs into a range of key decision-making processes in order to improve their effectiveness and transparency. This guidebook will assist transportation agency staff challenged with turning performance data into meaningful information that will influence agency decisions and actions.

This guidebook should be of immediate use to those who have mastered the basics of performance measurement but who will benefit from a deeper understanding of what similar organizations have done in order to successfully integrate these systems into key decision-making processes.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_660.pdf

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Research and Technology Implementation Office

October 2010

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Research Digest Item 18 A Guidebook for Corridor-Based Statewide Transportation Planning TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 661 • 2010 This guidebook provides a template for corridor planning that will assist states to better understand the implications of transportation decisions on mobility, communities, economic development, and environmental stewardship. The template can be a useful tool to help states program funds to meet identified needs and priorities.

This guidebook should be of immediate use to transportation decision makers, managers, and planning practitioners involved in the preparation of statewide transportation plans and priority programs.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_661.pdf

Item 19 Accelerating Transportation Project and Program Delivery : Conception to Completion TRANSPORTATION RESEARCH BOARD (TRB) NCHRP Report 662 • 2010 This report describes how selected transportation agencies have reduced the time required to complete the project delivery process. This process takes new or renewed transportation facilities and services from conception to completion, ready for users. Project delivery is a primary indicator of an agency’s effectiveness. Individual highway and other transportation projects are developed under programs intended to implement agency and legislative initiatives and other public policy. The way programs are organized and managed can determine the speed and efficiency of project development. Accelerating program functions can speed up project delivery. This report describes the experiences of eight state departments of transportation (DOTs) that made improvements in their project delivery and the lessons to be learned from their experiences.

The information will be useful to DOT managers seeking to ensure that their agencies’ organization, policies, and program operations facilitate project delivery.

Full-text PDF of this report is available for free download from: http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_662.pdf

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Research and Technology Implementation Office

October 2010

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