Rehabilitation of Concrete Pavements Utilizing Rebblization and Crack and Seat Methods, June 2005

Deterioration in portland cement concrete (PCC) pavements can occur due to distresses caused by a combination of traffic loads and weather conditions. Hot mix asphalt (HMA) overlay is the most commonly used rehabilitation technique for such deteriorated PCC pavements. However, the performance of these HMA overlaid pavements is hindered due to the occurrence of reflective cracking, resulting in significant reduction of pavement serviceability. Various fractured slab techniques, including rubblization, crack and seat, and break and seat are used to minimize reflective cracking by reducing the slab action. However, the design of structural overlay thickness for cracked and seated and rubblized pavements is difficult as the resulting structure is neither a “true” rigid pavement nor a “true” flexible pavement. Existing design methodologies use the empirical procedures based on the AASHO Road Test conducted in 1961. But, the AASHO Road Test did not employ any fractured slab technique, and there are numerous limitations associated with extrapolating its results to HMA overlay thickness design for fractured PCC pavements. The main objective of this project is to develop a mechanistic-empirical (ME) design approach for the HMA overlay thickness design for fractured PCC pavements. In this design procedure, failure criteria such as the tensile strain at the bottom of HMA layer and the vertical compressive strain on the surface of subgrade are used to consider HMA fatigue and subgrade rutting, respectively. The developed ME design system is also implemented in a Visual Basic computer program. A partial validation of the design method with reference to an instrumented trial project (IA-141, Polk County) in Iowa is provided in this report. Tensile strain values at the bottom of the HMA layer collected from the FWD testing at this project site are in agreement with the results obtained from the developed computer program.

Field Experiments of Current Concrete Pavement Surface Characteristics Practices: Iowa Data Collection and Analysis, December 2005

One of the most important issues in portland cement concrete pavement research today is surface characteristics. The issue is one of balancing surface texture construction with the need for durability, skid resistance, and noise reduction. The National Concrete Pavement Technology Center at Iowa State University, in conjunction with the Federal Highway Administration, American Concrete Pavement Association, International Grinding and Grooving Association, Iowa Highway Research Board, and other states, have entered into a three-part National Surface Characteristics Program to resolve the balancing problem. As a portion of Part 2, this report documents the construction of 18 separate pavement surfaces for use in the first level of testing for the national project. It identifies the testing to be done and the limitations observed in the construction process. The results of the actual tests will be included in the subsequent national study reports.

Identifying and Implementing Effective Training for Hispanic Craft Workers, American Supervisors, and DOT Inspectors: Phase III of the Hispanic Workforce Research Project, May 2006

The number of Hispanic workers in the U.S. construction industry has been steadily increasing, and language and cultural barriers have sometimes arisen on the jobsite. Due in part to these barriers, the number of fatalities among Hispanics at construction sites in 2001 jumped 24%, while construction fatalities overall dropped 3%. This study, which constitutes Phase III of the Hispanic Workforce Research Project, addresses these language and cultural barriers by investigating the most effective way to deliver training material developed in Phases I and II to Hispanic workers, American supervisors, and department of transportation (DOT) inspectors. The research methodology consisted of assessing the needs and interests of potential and current course participants in terms of exploring innovative ways to deliver the training. The training courses were then adapted and delivered to fit the specific needs of each audience. During Phase III of this project, the research team delivered the courses described in the Phase I and II reports to eight highway construction companies and two DOT groups. The courses developed in Phases I and II consist of four construction-focused language training courses that can be part of an effective training program to facilitate integration among U.S. and Hispanic workers, increase productivity and motivation at the jobsite, and decrease the existing high mortality rate for Hispanic workers. Moreover, the research team developed a course for the construction season called Toolbox Integration Course for Hispanic workers and American supervisors (TICHA), which consists of nine 45-minute modules delivered to one construction company over 11 weeks in the summer of 2005.

Study of Iowa's Current Road Use Tax Funds (RUTF) and Future Road Maintenance and Construction Needs, 2006

The 81st General Assembly of the Iowa Legislature, in Section 85 of House File 868, required the Iowa Department of Transportation (DOT) to conduct a study of current Road Use Tax Fund (RUTF)revenues, and projected roadway construction and maintenance needs.

Study of Iowa’s Current Road Use Tax Funds (RUTF) and Future Road Maintenance and Construction Needs, 2006

The 81st General Assembly of the Iowa legislature, in Section 85 of House File 868, required the Iowa Department of Transportation (Iowa DOT) to conduct a study of current Road Use Tax Fund (RUTF) revenues, and projected roadway construction and maintenance needs. With input from Iowa’s cities, counties and other interested groups, the Iowa DOT completed this report for submittal to the legislature.

Study of Iowa’s Current Road Use Tax Funds (RUTF) and Future Road Maintenance and Construction Needs, 2006

The 81st General Assembly of the Iowa legislature, in Section 85 of House File 868, required the Iowa Department of Transportation (Iowa DOT) to conduct a study of current Road Use Tax Fund (RUTF) revenues, and projected roadway construction and maintenance needs.

Developing a Simple and Rapid Test for Monitoring the Heat Evolution of Concrete Mixtures for Both Laboratory and Field Applications, January 2006

Various test methods exist for measuring heat of cement hydration; however, most current methods require expensive equipment, complex testing procedures, and/or extensive time, thus not being suitable for field application. The objectives of this research are to identify, develop, and evaluate a standard test procedure for characterization and quality control of pavement concrete mixtures using a calorimetry technique. This research project has three phases. Phase I was designed to identify the user needs, including performance requirements and precision and bias limits, and to synthesize existing test methods for monitoring the heat of hydration, including device types, configurations, test procedures, measurements, advantages, disadvantages, applications, and accuracy. Phase II was designed to conduct experimental work to evaluate the calorimetry equipment recommended from the Phase I study and to develop a standard test procedure for using the equipment and interpreting the test results. Phase II also includes the development of models and computer programs for prediction of concrete pavement performance based on the characteristics of heat evolution curves. Phase III was designed to study for further development of a much simpler, inexpensive calorimeter for field concrete. In this report, the results from the Phase I study are presented, the plan for the Phase II study is described, and the recommendations for Phase III study are outlined. Phase I has been completed through three major activities: (1) collecting input and advice from the members of the project Technical Working Group (TWG), (2) conducting a literature survey, and (3) performing trials at the CP Tech Center’s research lab. The research results indicate that in addition to predicting maturity/strength, concrete heat evolution test results can also be used for (1) forecasting concrete setting time, (2) specifying curing period, (3) estimating risk of thermal cracking, (4) assessing pavement sawing/finishing time, (5) characterizing cement features, (6) identifying incompatibility of cementitious materials, (7) verifying concrete mix proportions, and (8) selecting materials and/or mix designs for given environmental conditions. Besides concrete materials and mix proportions, the configuration of the calorimeter device, sample size, mixing procedure, and testing environment (temperature) also have significant influences on features of concrete heat evolution process. The research team has found that although various calorimeter tests have been conducted for assorted purposes and the potential uses of calorimeter tests are clear, there is no consensus on how to utilize the heat evolution curves to characterize concrete materials and how to effectively relate the characteristics of heat evolution curves to concrete pavement performance. The goal of the Phase II study is to close these gaps.

Lane Closure Policy Development, Enforcement, and Exceptions: A Survey of Seven State Transportation Agencies, February 2007

Traffic volume increases and an aging infrastructure create the need for reconstruction, rehabilitation, and maintenance of existing facilities. As more motorists feel that delays should be minimal during highway renewal projects, lane closures that reduce capacity through the work zone should not create unreasonable delays. In order to facilitate the determination of when a lane closure is permitted during the day, some state transportation agencies (STAs) have developed lane closure policies, or strategies, that they use as guidance in determining daily permitted lane closure times. Permitted lane closure times define what times of the day, week, or season a lane closure is allowed on a facility and at a specific location or segment. This research addresses the lane closure policies of several STAs that were reputed to have good lane closures policies or strategies and that were selected by the project advisory committee for further research.

Validation of the New Mix Design Process for Cold In-Place Rehabilitation Using Foamed Asphalt, 2007

Asphalt pavement recycling has grown dramatically over the last few years as a viable technology to rehabilitate existing asphalt pavements. Iowa's current Cold In-place Recycling (CIR) practice utilizes a generic recipe specification to define the characteristics of the CIR mixture. As CIR continues to evolve, the desire to place CIR mixture with specific engineering properties requires the use of a mix design process. A new mix design procedure was developed for Cold In-place Recycling using foamed asphalt (CIR-foam) in consideration of its predicted field performance. The new laboratory mix design process was validated against various Reclaimed Asphalt Pavement (RAP) materials to determine its consistency over a wide range of RAP materials available throughout Iowa. The performance tests, which include dynamic modulus test, dynamic creep test and raveling test, were conducted to evaluate the consistency of a new CIR-foam mix design process to ensure reliable mixture performance over a wide range of traffic and climatic conditions. The “lab designed” CIR will allow the pavement designer to take the properties of the CIR into account when determining the overlay thickness.

The Acute STroke Registry and Analysis of Lausanne (ASTRAL): design and baseline analysis of an ischemic stroke registry including acute multimodal imaging.

BACKGROUND AND PURPOSE: Stroke registries are valuable tools for obtaining information about stroke epidemiology and management. The Acute STroke Registry and Analysis of Lausanne (ASTRAL) prospectively collects epidemiological, clinical, laboratory and multimodal brain imaging data of acute ischemic stroke patients in the Centre Hospitalier Universitaire Vaudois (CHUV). Here, we provide design and methods used to create ASTRAL and present baseline data of our patients (2003 to 2008). METHODS: All consecutive patients admitted to CHUV between January 1, 2003 and December 31, 2008 with acute ischemic stroke within 24 hours of symptom onset were included in ASTRAL. Patients arriving beyond 24 hours, with transient ischemic attack, intracerebral hemorrhage, subarachnoidal hemorrhage, or cerebral sinus venous thrombosis, were excluded. Recurrent ischemic strokes were registered as new events. RESULTS: Between 2003 and 2008, 1633 patients and 1742 events were registered in ASTRAL. There was a preponderance of males, even in the elderly. Cardioembolic stroke was the most frequent type of stroke. Most strokes were of minor severity (National Institute of Health Stroke Scale [NIHSS] score ≤ 4 in 40.8% of patients). Cardioembolic stroke and dissections presented with the most severe clinical picture. There was a significant number of patients with unknown onset stroke, including wake-up stroke (n=568, 33.1%). Median time from last-well time to hospital arrival was 142 minutes for known onset and 759 minutes for unknown-onset stroke. The rate of intravenous or intraarterial thrombolysis between 2003 and 2008 increased from 10.8% to 20.8% in patients admitted within 24 hours of last-well time. Acute brain imaging was performed in 1695 patients (97.3%) within 24 hours. In 1358 patients (78%) who underwent acute computed tomography angiography, 717 patients (52.8%) had significant abnormalities. Of the 1068 supratentorial stroke patients who underwent acute perfusion computed tomography (61.3%), focal hypoperfusion was demonstrated in 786 patients (73.6%). CONCLUSIONS: This hospital-based prospective registry of consecutive acute ischemic strokes incorporates demographic, clinical, metabolic, acute perfusion, and arterial imaging. It is characterized by a high proportion of minor and unknown-onset strokes, short onset-to-admission time for known-onset patients, rapidly increasing thrombolysis rates, and significant vascular and perfusion imaging abnormalities in the majority of patients.

Cost system design and cost management in the Spanish public sector

Cost systems have been shown to have developed considerably in recent years andactivity-based costing (ABC) has been shown to be a contribution to cost management,particularly in service businesses. The public sector is composed to a very great extentof service functions, yet considerably less has been reported of the use of ABC tosupport cost management in this sector.In Spain, cost systems are essential for city councils as they are obliged to calculate thecost of the services subject to taxation (eg. waste collection, etc). City councils musthave a cost system in place to calculate the cost of services, as they are legally requirednot to profit , from these services.This paper examines the development of systems to support cost management in theSpanish Public Sector. Through semi-structured interviews with 28 subjects within oneCity Council it contains a case study of cost management. The paper contains extractsfrom interviews and a number of factors are identified which contribute to thesuccessful development of the cost management system.Following the case study a number of other City Councils were identified where activity-based techniques had either failed or stalled. Based on the factors identified inthe single case study a further enquiry is reported. The paper includes a summary usingstatistical analysis which draws attention to change management, funding and politicalincentives as factors which had an influence on system success or failure.

The Effects of Headcut and Knickpoint Propagation on Bridges in Iowa, October 2008

Headcuts (known also as primary knickpoints) and knickpoints (known also as secondary knickpoints) have been found to contribute to the accelerated riverbed degradation problem in the midwestern United States. Step-changes that occur at the head of channel networks are referred to as headcuts, and those that occur within the confines of channel banks are referred to as knickpoints. The formation of headcuts and knickpoints and their upstream migration have been linked to the over-steepening of stream reaches when the flow plunges to the bed and creates a plunge pool. Secondary flow currents and seepage are believed to be some other parameters contributing to the formation and evolution of headcuts and knickpoints. Ongoing research suggests that headcuts and knickpoints, where they form and migrate, may account for 60% (or more) of the bed erosion in the streams. Based on preliminary observations, there is a strong indication that headcuts and knickpoints can also have a greater influence on flow thalweg alignment (line of deepest flow) for small rivers. A shift in thalweg toward a riverbank or embankment is usually a prime factor contributing to riverbank erosion and scour.

Relocation Assistance and Advisory Services, March 24, 2009

This brochure provides general information about relocation assistance provided by the Iowa Department of Transportation (DOT) for those individuals who may be required to move as a result of a highway project. It is not intended to be a legal document that comprehensively explains every right or obligation you have as established by Chapter 316, Code of Iowa; Federal Public Laws 91-646 and 100-17; and 49 CFR. Your relocation adviser will provide the assistance you need to successfully relocate to a suitable replacement property. Your first contact with your relocation adviser will usually occur during the early stages of the appraisal process, and he or she will continue to work with you until you have moved and become established at a new location. Do not hesitate to ask questions so you are sure you understand the process, your rights and the benefits available to you. Please let your DOT relocation adviser know your needs and preferences. If your relocation adviser is unable to help you with a specific problem or concern, he or she may know of another person or an organization that can help you. DO NOT MOVE UNTIL YOU HAVE CONTACTED YOUR DOT RELOCATION ADVISER. Only then will you be sure you are not jeopardizing your potential rights and benefits under this program. No person who lawfully occupies real property will be required by DOT to move without being notified in writing at least 90 days in advance.

Office of Location and Environment Manual, August 2009

This manual captures the experience of practitioners in the Iowa Department of Transportation’s (Iowa DOT’s) Office of Location and Environment (OLE). It also documents the need for coordinated project development efforts during the highway project planning, or location study phase and engineering design. The location study phase establishes: * The definition of, and need for, the highway improvement project * The range of alternatives and many key attributes of the project’s design * The recommended alternative, its impacts, and the agreed-to conditions for project approval The location study process involves developing engineering alternatives, collecting engineering and environmental data, and completing design refinements to accomplish functional designs. The items above also embody the basic content required for projects compliant with the National Environmental Policy Act (NEPA) of 19691, which directs federal agencies to use a systematic, interdisciplinary approach during the planning process whenever proposed actions (or “projects”) have the potential for environmental impacts. In doing so, NEPA requires coordination with stakeholders, review, comment, and public disclosure. Are location studies and environmental studies more about the process or the documents? If properly conducted, they concern both—unbiased and reasonable processes with quality and timely documents. In essence, every project is a story that needs to be told. Engineering and environmental regulations and guidance, as documented in this manual, will help project staff and managers become better storytellers.

New multiple matched filter: design and experimental realization

A method of making a multiple matched filter which allows the recognition of different characters in successive planes in simple conditions is proposed. The generation of the filter is based on recording on the same plate the Fourier transforms of the different patterns to be recognized, each of which is affected by different spherical phase factors because the patterns have been placed at different distances from the lens. This is proved by means of experiments with a triple filter which allows satisfactory recognition of three characters.