Analysis of Current State Rigid Pavement Design Practices in the United States

1996 ◽  
Vol 1525 (1) ◽  
pp. 72-82
Author(s):  
Y. Jiang ◽  
M. I. Darter ◽  
E. Owusu-Antwi
Keyword(s):  
United States ◽  
Concrete Slab ◽  
The United States ◽  
Concrete Pavement ◽  
Pavement Design ◽  
Portland Cement Concrete ◽  
Design Features ◽  
Climatic Regions ◽  
Design Practices ◽  
State Highway

Current portland cement concrete pavement design practices and the key concrete pavement design features used by state highway agencies in the United States are summarized. This information was obtained from a comprehensive survey conducted in 1994 and 1995 under an NCHRP project. Pavement types, design methodologies, and reliability levels are included, along with many design inputs. Parameters that the states use to characterize pavement site conditions, including climate, subgrade, and traffic conditions, are given. The designed concrete slab thicknesses for different site condition combinations are compared. An analysis of variance was conducted to compare the mean slab thicknesses designed in different climatic regions. This examination and summary of the details of current pavement design practices and design features for concrete pavements in the United States will be of interest to both pavement researchers and practitioners.

So You Want a Carbon Tax: How Do You Design It?

2019 ◽  
pp. 99-114
Author(s):  
Gilbert E. Metcalf
Keyword(s):  
United States ◽  
Carbon Dioxide ◽  
Carbon Dioxide Emissions ◽  
Carbon Tax ◽  
The United States ◽  
Global Trade ◽  
Design Features ◽  
Practical Advice ◽  
Traded Goods ◽  
The Government

This chapter reviews the nuts and bolts of implementing a carbon tax. Invoking principles of administrative simplicity, ease of compliance, and avoidance of design features that dilute the price signal, it gives practical advice on who should be responsible for collecting the tax and remitting it to the government. It explains how the tax should handle the possibility that we can capture and permanently store carbon dioxide emissions and how we should tax emissions related to internationally traded goods so the United States is not disadvantaged in global trade. Finally, it identifies, and warns policymakers away from, various pitfalls in carbon tax design.

An evaluation of warranty contracting in the United States of America

2006 ◽  
Vol 33 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Mehmet Emre Bayraktar ◽  
Qingbin Cui ◽  
Makarand Hastak ◽  
Issam Minkarah
Keyword(s):  
United States ◽  
United States Of America ◽  
The United States ◽  
Department Of Transportation ◽  
Construction Costs ◽  
Advantages And Disadvantages ◽  
Contract Administration ◽  
State Highway ◽  
Early Failures ◽  
State Highway Agencies

It is believed that warranty contracting would benefit state highway agencies by improving quality, saving money and time, and encouraging contractors' innovations. However, the challenges associated with warranties could be substantial, including higher costs, early failures, a reduction or even elimination of small contractors from the bidding process, and an increase in contract disputes and litigation. The actual impact of warranty provisions on state Department of Transportation (DOT) projects in the United States of America is still unclear because of limited industry experience. This paper provides a detailed discussion of warranty provisions and the benefits and problems associated with the subject matter. The advantages and disadvantages of warranty provisions are evaluated from the conflicting perspectives of state Departments of Transportation (DOTs), contractors, and surety companies. The future prospects of warranty provisions are established based on the findings of a recent study of warranty provisions and existing literature. Also, several options are proposed that have a strong potential to improve the application of warranties on DOT projects.Key words: warranties, highway construction, innovation, highway maintenance, contract administration, construction costs, construction inspection.

scholarly journals Healthcare Reform Repeal Efforts in the United States in 2017: An Inquiry into Public Advocacy Efforts by Key Interest Groups

2018 ◽  
Vol 6 (3) ◽  
pp. 190-204
Author(s):  
John Hoornbeek ◽  
Bethany Lanese ◽  
Mutlaq Albugmi ◽  
Joshua Filla
Keyword(s):  
United States ◽  
Health Insurance ◽  
Interest Groups ◽  
Interest Group ◽  
Healthcare Reform ◽  
The United States ◽  
Business Community ◽  
Policy Feedback ◽  
Design Features ◽  
Feedback Effects

The Affordable Care Act (ACA) was subjected to repeated repeal and replace efforts in the United States Congress in 2017. Attempts to repeal and replace the law failed, but penalties for not complying with its mandate that individuals purchase health insurance were removed in tax legislation passed late in the year and administrative actions taken by President Trump yielded additional concerns about the stability of the law’s reform approach and the expanded health insurance access that it created. This article explores public advocacy efforts by key interest groups from three major policy sectors—health providers, the insurance industry, and the business community—that had served as an “axis of opposition” to past American healthcare reform efforts. It identifies resource and incentive policy feedback effects that appear likely to influence these groups due to design features of the ACA and assesses whether patterns of advocacy efforts in 2017 are consistent with what might be expected if these design features had their predicted effects. Our assessment reveals patterns of interest group advocacy that are consistent with what might be expected to arise from resource and incentive based policy feedback effects, and interest group political dynamics that differ from what was in place prior to passage of the ACA. It also reveals advocacy patterns that are not well explained by resource and incentive based policy feedback effects, and—in so doing—yields insights that are relevant to the design of policy reforms and future research.

scholarly journals Can Precipitation and Temperature from Meteorological Reanalyses Be Used for Hydrological Modeling?

2016 ◽  
Vol 17 (7) ◽  
pp. 1929-1950 ◽  
Author(s):  
Gilles R. C. Essou ◽  
Florent Sabarly ◽  
Philippe Lucas-Picher ◽  
François Brissette ◽  
Annie Poulin
Keyword(s):  
United States ◽  
Hydrological Modeling ◽  
The United States ◽  
Hydrological Models ◽  
River Flows ◽  
Surface Precipitation ◽  
Climatic Regions ◽  
Precipitation Seasonality ◽  
Regional Reanalysis ◽  
Precipitation And Temperature

Abstract This paper investigates the potential of reanalyses as proxies of observed surface precipitation and temperature to force hydrological models. Three global atmospheric reanalyses (ERA-Interim, CFSR, and MERRA), one regional reanalysis (NARR), and one global meteorological forcing dataset obtained by bias-correcting ERA-Interim [Water and Global Change (WATCH) Forcing Data ERA-Interim (WFDEI)] were compared to one gridded observation database over the contiguous United States. Results showed that all temperature datasets were similar to the gridded observation over most of the United States. On the other hand, precipitation from all three global reanalyses was biased, especially in summer and winter in the southeastern United States. The regional reanalysis precipitation was closer to observations since it indirectly assimilates surface precipitation. The WFDEI dataset was generally less biased than the reanalysis datasets. All datasets were then used to force a global conceptual hydrological model on 370 watersheds of the Model Parameter Estimation Experiment (MOPEX) database. River flows were computed for each watershed, and results showed that the flows simulated using NARR and gridded observations forcings were very similar to the observed flows. The simulated flows forced by the global reanalysis datasets were also similar to the observations, except in the humid continental and subtropical climatic regions, where precipitation seasonality biases degraded river flow simulations. The WFDEI dataset led to better river flows than reanalysis in the humid continental and subtropical climatic regions but was no better than reanalysis—and sometimes worse—in other climatic zones. Overall, the results indicate that global reanalyses have good potential to be used as proxies to observations to force hydrological models, especially in regions with few weather stations.

Comprehensive Bridge Scour Evaluation Methodology

2000 ◽  
Vol 1696 (1) ◽  
pp. 204-208 ◽  
Author(s):  
P. F. Lagasse ◽  
E. V. Richardson ◽  
L. W. Zevenbergen
Keyword(s):  
United States ◽  
Highway Bridges ◽  
The United States ◽  
Annotated Bibliography ◽  
Evaluation Methodology ◽  
Bridge Scour ◽  
State Highway ◽  
Existing Bridges ◽  
State Highway Agencies ◽  
Stream Instability

In the United States, bridge scour technology is discussed primarily in three FHWA publications: Hydraulic Engineering Circular (HEC) 18: Evaluating Scour at Bridges; HEC-2: Stream Stability at Highway Structures; and HEC-23: Bridge Scour and Stream Instability Countermeasures. Together, these documents provide guidance to state highway agencies that is necessary for completing comprehensive scour and stream instability evaluations for the design of new bridges and for repairing existing bridges. Experience has shown that the relationships among the three documents are not always readily apparent, and some scour evaluations have relied primarily on HEC-18. A comprehensive flowchart that illustrates the interrelationship among the three FHWA scour-related documents has been developed. In addition, in 1998, FHWA, TRB, and AASHTO sponsored a scanning review of European practice for bridge scour and stream instability countermeasures. In 1999, ASCE published a compendium of papers on stream stability and scour at highway bridges, and FHWA prepared an annotated bibliography to support revisions to the three HECs. It is anticipated that the flow-chart and the substantial information from the scanning review, the compendium, and the annotated bibliography will be included in the next revisions to HEC-18, HEC-20, and HEC-23. On the basis of information from these sources, a comprehensive approach to bridge scour and stream instability evaluations is outlined, and an overview of planned revisions to the three FHWA HECs is provided.

Measurement and Significance of the Coefficient of Thermal Expansion of Concrete in Rigid Pavement Design

2005 ◽  
Vol 1919 (1) ◽  
pp. 38-46 ◽  
Author(s):  
Jagannath Mallela ◽  
Ala Abbas ◽  
Tom Harman ◽  
Chetana Rao ◽  
Rongfang Liu ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Structural Design ◽  
Coefficient Of Thermal Expansion ◽  
Test Procedure ◽  
Fundamental Property ◽  
The United States ◽  
Concrete Pavement ◽  
Pavement Design ◽  
Pavement Performance ◽  
Opening And Closing

The coefficient of thermal expansion (CTE) is a fundamental property of concrete. It has long been known to have an effect on joint opening and closing in jointed plain concrete pavement, crack formation and opening and closing in continuously reinforced concrete pavement, and curling stresses and thermal deformations in both types of pavements. However, it has not been included as a variable either in materials specifications or in the structural design of concrete pavements. Hundreds of cores were taken from Long-Term Pavement Performance sections throughout the United States and were tested by FHWA's Turner–Fairbank Highway Research Center laboratory, using the AASHTO TP 60 test procedure. The CTE values were then assimilated into groups on the basis of aggregate types, and the mean and range of CTE were calculated. These results were then used in the new mechanistic–empirical pavement design guide to determine the significance of the measured range of CTE on concrete pavement performance. The CTE of the concrete was found to vary widely, depending on the predominant aggregate type used in the concrete. Sensitivity analysis showed CTE to have a significant effect on slab cracking and, to a lesser degree, on joint faulting. Its overall effect on smoothness was also significant. Given that CTE has not been used before in routine pavement structural design, the conclusion is that this design input is too sensitive to be ignored and must be fully considered in specifications and in the design process to reduce the risk of excessive cracking, faulting, and loss of smoothness.

scholarly journals Quantifying the Impact of Climate Change on Flexible Pavement Performance and Lifetime in the United States

2019 ◽  
Vol 2673 (1) ◽  
pp. 110-122 ◽  
Author(s):  
Anne M. K. Stoner ◽  
Jo Sias Daniel ◽  
Jennifer M. Jacobs ◽  
Katharine Hayhoe ◽  
Ian Scott-Fleming
Keyword(s):  
Climate Change ◽  
United States ◽  
Global Climate Model ◽  
Flexible Pavement ◽  
The United States ◽  
Pavement Design ◽  
Pavement Performance ◽  
Climate Projections ◽  
Impact Of Climate Change ◽  
The Impact

Flexible pavement design requires considering a variety of factors including the materials used, variations in water tables, traffic levels, and the climatic conditions the road will experience over its lifetime. Most pavement designs are based on historical climate variables such as temperature and precipitation that are already changing across much of the United States, and do not reflect projected trends. As pavements are typically designed to last 20 years or more, designs that do not account for current and future trends can result in reduced performance. However, incorporating climate projections into pavement design is not a trivial exercise. Significant mismatches in both spatial and temporal scale challenge the integration of the latest global climate model simulations into pavement models. This study provides a national-level overview of what the impact of climate change to flexible pavement could look like, and where regional focus should be placed. It also demonstrates a new approach to developing high-resolution spatial and temporal projections that generates hourly information at the scale of individual weather stations, and applies this as input to the AASHTOWare Pavement ME Design™ model. The impact of three different future climates on pavement performance and time to reach failure thresholds in 24 locations across the United States are quantified. Changes to projected pavement performance differ by location, but nearly all result in decreased performance under current design standards. The largest increases in distress are observed for permanent deformation measures, especially toward the end of the century under greater increases in temperature.

Integrating potential climate change into the mechanistic–empirical based pavement design

2013 ◽  
Vol 40 (12) ◽  
pp. 1173-1183 ◽  
Author(s):  
Qiang Joshua Li ◽  
Leslie Mills ◽  
Sue McNeil ◽  
Nii O. Attoh-Okine
Keyword(s):  
Climate Change ◽  
United States ◽  
The United States ◽  
Adaptation Strategy ◽  
Climatic Conditions ◽  
Pavement Design ◽  
Pavement Performance ◽  
Climate Change Effects ◽  
And Performance ◽  
Potential Climate Change

Given anticipated climate change and its inherent uncertainty, a pavement could be subjected to different climatic conditions over its life and might be inadequate to withstand future environmental stresses beyond those currently considered during pavement design. This paper incorporates climate change effects into the mechanistic–empirical (M-E) based pavement design to explore potential climate change and its uncertainty on pavement design and performance. Three important questions are addressed: (1) How does pavement performance deteriorate differently with climate change and its uncertainty? (2) What is the risk if climate change and its uncertainty are not considered in design? and (3) How do pavement designers respond and incorporate this change into M-E design ? Three test sites in the United States are examined and results demonstrate a robust and effective approach to integrate climate change into pavement design as an adaptation strategy.

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