EPI Update, November 7, 2014

Weekly newsletter for Center For Acute Disease Epidemiology of Iowa Department of Public Health.

EPI Update, November 14, 2014

Weekly newsletter for Center For Acute Disease Epidemiology of Iowa Department of Public Health.

EPI Update, November 21, 2014

Weekly newsletter for Center For Acute Disease Epidemiology of Iowa Department of Public Health.

EPI Update, December 5, 2014

Weekly newsletter for Center For Acute Disease Epidemiology of Iowa Department of Public Health.

EPI Update, December 12, 2014

Weekly newsletter for Center For Acute Disease Epidemiology of Iowa Department of Public Health.

EPI Update, December 19, 2014

Weekly newsletter for Center For Acute Disease Epidemiology of Iowa Department of Public Health.

Study of the Regulatory Issues Affecting Truck Freight Movement in the Midwest, RB29-013, 2014

This project investigated regulatory issues that may affect or limit freight movement in Iowa and other Midwest states: Illinois, Kansas, Minnesota, Missouri, Nebraska, South Dakota, and Wisconsin. Current state regulations for the following are reviewed and summarized: - Vehicle dimensions - Vehicle weights - Speed limits - Weight compliance enforcement - Fees and taxes - Driver qualifications - Medical certification - Hours of service - Oversize-overweight permits

Audit report on the City of Wilton, Iowa for the year ended June 30, 2014

Audit report on the City of Wilton, Iowa for the year ended June 30, 2014

Effects of Road Construction Intensity and Operations on Rural Freeway Work Zone Capacity, TPF-5(081), 2014

Capacity is affected by construction type and its intensity on adjacent open traffic lanes. The effect on capacity is a function of vehicles moving in and out of the closed lanes of the work zone, and the presence of heavy construction vehicles. Construction activity and its intensity, however, are not commonly considered in estimating capacity of a highway lane. The main purpose of this project was to attempt to quantify the effects of construction type and intensity (e.g. maintenance, rehabilitation, reconstruction, and milling) on work zone capacity. The objective of this project is to quantify the effects of construction type and its intensity on work zone capacity and to develop guidelines for MoDOT to estimate the specific operation type and intensity that will improve the traffic flow by reducing the traffic flow and queue length commonly associated with work zones. Despite the effort put into field data collection, the data collected did not show a full speed-flow chart therefore extracting a reliable capacity value was difficult. A statistical comparison between the capacity values found in this study using either methodologies indicates that there is an effect of construction activity on the values work zone capacity. It was found that the heavy construction activity reduces the capacity. It is very beneficial to conduct similar studies on the capacity of work zone with different lane closure barriers, which is also directly related to the type of work zone being short-term or long-term work zones. Also, the effect of different geometric and environmental characteristics of the roadway should be considered in future studies.

Audit report on the City of Fairfield, Iowa for the year ended June 30, 2014

Audit report on the City of Fairfield, Iowa for the year ended June 30, 2014

Agreed-upon procedures report on the City of Derby, Iowa for the period August 1, 2013 through July 31, 2014

Agreed-upon procedures report on the City of Derby, Iowa for the period August 1, 2013 through July 31, 2014

Audit report on the Peace Officers' Retirement, Accident and Disability System for the year ended June 30, 2014

Audit report on the Peace Officers' Retirement, Accident and Disability System for the year ended June 30, 2014

Multidisciplinary Safety Team (MDST) Factors of Success, 2014

This project included a literature review and summary that focused on subjects related to team building, team/committee member motivational strategies, and tools for effective and efficient committee meetings. It also completed an online survey of multidisciplinary safety team (MDST) members that focused on methods to increase meeting attendance and the identification of factors that make MDSTs successful. The survey had a response rate of about 15 percent. Finally, three small MDST focus groups were held and the participants discussed information similar to that investigated by the online survey. The results of these three activities were similar and complementary. In general, the outcomes of all three tasks show that a well-designed agenda that has items relevant to the meeting attendees is very important. In addition, the literature, online survey, and focus group results identified other characteristics that define a good team or MDST. Some of these characteristics included effective and consistent leadership, members that are allowed to provide input and have an impact, members that are vested in the activities of the group, and a match between the interests of the members and the focus/mission/purpose of the meetings/group. Meetings that are scheduled well in advance of the meeting date, include time for networking, local safety activity discussions, hands-on activities/tasks, and/or some type of educational or informational presentation or activity also appeared to be the most desirable. Lastly, it was shown that MDSTs can thrive and be successful through various means, but the ability to focus on a specific safety issue when the group is first organized was suggested as a benefit that could be of assistance for long-term sustainability.

Safety and Mobility Impacts of Winter Weather --Phase 3, SPR RB01-012, 2014

Highway agencies spend millions of dollars to ensure safe and efficient winter travel. However, the effectiveness of winter-weather maintenance practices on safety and mobility are somewhat difficult to quantify. Safety and Mobility Impacts of Winter Weather - Phase 1 investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter-weather conditions. In Phase 2, three Iowa Department of Transportation (DOT) high-priority sites were evaluated and realistic maintenance and operations mitigation strategies were also identified. In this project, site prioritization techniques for identifying roadway segments with the potential for safety improvements related to winter-weather crashes, were developed through traditional naïve statistical methods by using raw crash data for seven winter seasons and previously developed metrics. Additionally, crash frequency models were developed using integrated crash data for four winter seasons, with the objective of identifying factors that affect crash frequency during winter seasons and screening roadway segments using the empirical Bayes technique. Based on these prioritization techniques, 11 sites were identified and analyzed in conjunction with input from Iowa DOT district maintenance managers and snowplow operators and the Iowa DOT Road Weather Information System (RWIS) coordinator.

Development of Preliminary Load and Resistance Factor Design of Drilled Shafts in Iowa, RB03-012, 2014

The Federal Highway Administration (FHWA) mandated utilizing the Load and Resistance Factor Design (LRFD) approach for all new bridges initiated in the United States after October 1, 2007. To achieve part of this goal, a database for Drilled Shaft Foundation Testing (DSHAFT) was developed and reported on by Garder, Ng, Sritharan, and Roling in 2012. DSHAFT is aimed at assimilating high-quality drilled shaft test data from Iowa and the surrounding regions. DSHAFT is currently housed on a project website (http://srg.cce.iastate.edu/dshaft) and contains data for 41 drilled shaft tests. The objective of this research was to utilize the DSHAFT database and develop a regional LRFD procedure for drilled shafts in Iowa with preliminary resistance factors using a probability-based reliability theory. This was done by examining current design and construction practices used by the Iowa Department of Transportation (DOT) as well as recommendations given in the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications and the FHWA drilled shaft guidelines. Various analytical methods were used to estimate side resistance and end bearing of drilled shafts in clay, sand, intermediate geomaterial (IGM), and rock. Since most of the load test results obtained from O-cell do not pass the 1-in. top displacement criterion used by the Iowa DOT and the 5% of shaft diameter for top displacement criterion recommended by AASHTO, three improved procedures are proposed to generate and extend equivalent top load-displacement curves that enable the quantification of measured resistances corresponding to the displacement criteria. Using the estimated and measured resistances, regional resistance factors were calibrated following the AASHTO LRFD framework and adjusted to resolve any anomalies observed among the factors. To illustrate the potential and successful use of drilled shafts in Iowa, the design procedures of drilled shaft foundations were demonstrated and the advantages of drilled shafts over driven piles were addressed in two case studies.