Ultra-Thin PCC Overlays, January 2005

· Evaluate conventional methods of slab removal and asphalt surface preparation for subsequent overlays of portland cement concrete (PCC) in the “remove and replace” areas. · Evaluate existing asphaltic concrete surface under the “remove and patch” areas of rehabilitation areas and evaluate joint formation in the areas of patching. · Evaluate polypropylene fiber enhanced concrete at the three-inch depth to determine the cost/benefit of its inclusion. · Evaluate the performance of the rehabilitated ultra-thin whitetopping sections and the extended performance of the existing ultra-thin sections with and without patching. · Validate existing ultra-thin whitetopping design procedures of the Portland Cement Association (PCA) and American Concrete Pavement Association (ACPA) for application in Iowa.

Ultra-Thin Portland Cement Concrete Overlay Extended Evaluation, January 2005

In this day of the mature highway systems, a new set of problems is facing the highway engineer. The existing infrastructure has aged to or past the design life of the original pavement design. In many cases, increased commercial traffic is creating the need for additional load carrying capacity, causing state highway engineers to consider new alternatives for rehabilitation of existing surfaces. Alternative surface materials, thicknesses, and methods of installation must be identified to meet the needs of individual pavements and budgets. With overlays being one of the most frequently used rehabilitation alternatives, it is important to learn more about the limitations and potential performance of thin bonded portland cement overlays and subsequent rehabilitation. The Iowa ultra-thin project demonstrated the application of thin portland cement concrete overlays as a rehabilitation technique. It combined the variables of base preparation, overlay thickness, slab size, and fiber enhancement into a series of test sections over a 7.2-mile length. This report identifies the performance of the overlays in terms of deflection reduction, reduced cracking, and improved bonding between the portland cement concrete (PCC) and asphalt cement concrete (ACC) base layers. The original research project was designed to evaluate the variables over a 5-year period of time. A second project provided the opportunity to test overlay rehabilitation techniques and continue measurement of the original overlay performance for 5 additional years. All performance indicators identified exceptional performance over the 10-year evaluation period for each of the variable combinations considered. The report summarizes the research methods, results, and identifies future research ideas to aid the pavement overlay designer in the successful implementation of ultra-thin portland cement concrete overlays as an lternative pavement rehabilitation technique.

Design and Evaluation of a Single-Span Bridge Using Ultra- High Performance Concrete, September 2009

Research presented herein describes an application of a newly developed material called Ultra-High Performance Concrete (UHPC) to a single-span bridge. The two primary objectives of this research were to develop a shear design procedure for possible code adoption and to provide a performance evaluation to ensure the viability of the first UHPC bridge in the United States. Two other secondary objectives included defining of material properties and understanding of flexural behavior of a UHPC bridge girder. In order to obtain information in these areas, several tests were carried out including material testing, large-scale laboratory flexure testing, large-scale laboratory shear testing, large-scale laboratory flexure-shear testing, small-scale laboratory shear testing, and field testing of a UHPC bridge. Experimental and analytical results of the described tests are presented. Analytical models to understand the flexure and shear behavior of UHPC members were developed using iterative computer based procedures. Previous research is referenced explaining a simplified flexural design procedure and a simplified pure shear design procedure. This work describes a shear design procedure based on the Modified Compression Field Theory (MCFT) which can be used in the design of UHPC members. Conclusions are provided regarding the viability of the UHPC bridge and recommendations are made for future research.

Design and Performance Verifcation of Ultra-High Performance Concrete Piles for Deep Foundations Final Report, November 2008

The strategic plan for bridge engineering issued by AASHTO in 2005 identified extending the service life and optimizing structural systems of bridges in the United States as two grand challenges in bridge engineering, with the objective of producing safer bridges that have a minimum service life of 75 years and reduced maintenance cost. Material deterioration was identified as one of the primary challenges to achieving the objective of extended life. In substructural applications (e.g., deep foundations), construction materials such as timber, steel, and concrete are subjected to deterioration due to environmental impacts. Using innovative and new materials for foundation applications makes the AASHTO objective of 75 years service life achievable. Ultra High Performance Concrete (UHPC) with compressive strength of 180 MPa (26,000 psi) and excellent durability has been used in superstructure applications but not in geotechnical and foundation applications. This study explores the use of precast, prestressed UHPC piles in future foundations of bridges and other structures. An H-shaped UHPC section, which is 10-in. (250-mm) deep with weight similar to that of an HP10×57 steel pile, was designed to improve constructability and reduce cost. In this project, instrumented UHPC piles were cast and laboratory and field tests were conducted. Laboratory tests were used to verify the moment-curvature response of UHPC pile section. In the field, two UHPC piles have been successfully driven in glacial till clay soil and load tested under vertical and lateral loads. This report provides a complete set of results for the field investigation conducted on UHPC H-shaped piles. Test results, durability, drivability, and other material advantages over normal concrete and steel indicate that UHPC piles are a viable alternative to achieve the goals of AASHTO strategic plan.

2010 Iowa Medicaid – Birth Certificate – Barriers to Prenatal Care Project Match Report Summary of Findings for Medicaid Reimbursed Births

The purpose of the fact sheet is to summarize the Iowa Barriers to Prenatal Care Project’s survey results for women with Medicaid reimbursed births during 2010. This information will be used to guide decision makers in implementing programs that improve the health outcomes of the women and infants who rely on Medicaid coverage.

Iowa Ultra Thin Whitetopping at Two Years of Age, HR-559, 1996

An 11.6 km research project was constructed in 1994 on a portion of Iowa Highway 21 in Iowa County, from U.S. 6 to Iowa Highway 212. This research is intended to evaluate the effect of four primary variables on long term performances of the PCC concrete overlay, commonly called whitetopping. The variables are thickness (50 mm, 100 mm, 150 mm, and 200 mm), joint spacing (0.6 m squares, 1.2 m squares, 1.8 m squares, and 4.6 m spacing), fiber use (concrete with and without polypropolene fibers) and surface preparation (patch only, scarifying the surface, and cold-in-place recycling). After two years, only two sections exhibit a small amount of debonding and distress cracking. Both sections are 50 mm thick. Within each of these two sections, only 2% of the area is affected. Two other 50 mm thick sections have a small number of cracks but no debonding has been found. No adverse effects of these cracks are evident. Three asphalt overlay sections were also constructed. In each asphalt section, transverse cracks have recently been found. At two years of age, the research sections are performing very well. An insignificant number of cracks and no distressed areas have been found in any research sections thicker than 50 mm.

Iowa's Barriers to Prenatal Care Project, August 2013

The findings in this summary are based on the Iowa Barriers to Prenatal Care project. Ongoing since 1991, the purpose of this project is to obtain brief, accurate information about women delivering babies in Iowa hospitals. Specifically, the project seeks to learn about women’s experiences getting prenatal or delivery care during their current pregnancy. Other information is included which may be pertinent to health planners or those concerned with the systematic development of health care services. This project is a cooperative venture of all of Iowa’s maternity hospitals, the University of Northern Iowa Center for Social and Behavioral Research, and the Iowa Department of Public Health. The Robert Wood Johnson Foundation funded the first three years of this project. The current funding is provided by the Iowa Department of Public Health. The Director is Dr. Mary Losch, University of Northern Iowa Center for Social and Behavioral Research. The Coordinator for the project is Rodney Muilenburg. The questionnaire is distributed to nearly ninety maternity hospitals across the state of Iowa. Nursing staff or those responsible for obtaining birth certificate information in the obstetrics unit are responsible for approaching all birth mothers prior to dismissal and requesting their participation in the study. The questionnaire takes approximately ten minutes to complete. Completed questionnaires are returned to the University of Northern Iowa Center for Social and Behavioral Research for data entry and analysis. Returns are made monthly, weekly, or biweekly depending on the number of births per week in a given hospital. Except in the case of a mother who is too ill to complete the questionnaire, all mothers are eligible to be recruited for participation. The present yearly report includes an analysis of large Iowa cities, African American mothers, and a trend analysis of the last ten years. Also presented in this report is a frequency analysis of all variables included in the 2012 questionnaire. Unless otherwise noted, all entries reflect percentages. Please note that because percentages were rounded, total values may not equal 100%. Data presented are based upon 2012 questionnaires received to date (n = 23,674). All analyses reflect unweighted percentages of those responding.

Design, Construction, and Field Testing of an Ultra High Performance Concrete Pi-Girder Bridge, TR-574, 2011

Among the variety of road users and vehicle types that travel on U.S. public roadways, slow moving vehicles (SMVs) present unique safety and operations issues. SMVs include vehicles that do not maintain a constant speed of 25 mph, such as large farm equipment, construction vehicles, or horse-drawn buggies. Though the number of crashes involving SMVs is relatively small, SMV crashes tend to be severe. Additionally, SMVs can be encountered regularly on non-Interstate/non-expressway public roadways, but motorists may not be accustomed to these vehicles. This project was designed to improve transportation safety for SMVs on Iowa’s public roadway system. This report includes a literature review that shows various SMV statistics and laws across the United States, a crash study based on three years of Iowa SMV crash data, and recommendations from the SMV community.

Iowa's Barriers to Prenatal Care Project, July 2015

The findings in this summary are based on the Iowa Barriers to Prenatal Care project. Ongoing since 1991, the purpose of this project is to obtain brief, accurate information about women delivering babies in Iowa hospitals. Specifically, the project seeks to learn about women’s experiences getting prenatal or delivery care during their current pregnancy. Other information is included which may be pertinent to health planners or those concerned with the systematic development of health care services. This project is a cooperative venture of all of Iowa’s maternity hospitals, the University of Northern Iowa Center for Social and Behavioral Research, and the Iowa Department of Public Health. The Robert Wood Johnson Foundation funded the first three years of this project. The current funding is provided by the Iowa Department of Public Health. The Director is Dr. Mary Losch, University of Northern Iowa Center for Social and Behavioral Research. The Coordinator for the project is Rodney Muilenburg. The questionnaire is distributed to nearly ninety maternity hospitals across the state of Iowa. Nursing staff or those responsible for obtaining birth certificate information in the obstetrics unit are responsible for approaching all birth mothers prior to dismissal to request their participation in the study. The questionnaire takes approximately ten minutes to complete. Completed questionnaires are returned to the University of Northern Iowa Center for Social and Behavioral Research for data entry and analysis. Returns are made monthly, weekly, or biweekly depending on the number of births per week in a given hospital. Except in the case of a mother who is too ill to complete the questionnaire, all mothers are eligible to be recruited for participation. The present yearly report includes an analysis of large Iowa cities, frequencies by income, and a trend analysis of the last ten years. Also presented in this report is a frequency analysis of all variables included in the 2014 questionnaire. Unless otherwise noted, all entries reflect percentages. Please note that, because percentages were rounded, total values may not equal 100%. Data presented are based upon 2014 questionnaires received to date (n = 24,696). All analyses reflect unweighted percentages of those responding.