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.

Multi-Purpose ESS/ITS Data Collection Sites, SPR72-00-0003-042, 2014

This document presents the results of a state-of-practice survey of transportation agencies that are installing intelligent transportation sensors (ITS) and other devices along with their environmental sensing stations (ESS) also referred to as roadway weather information system (RWIS) assets.

Electronic Construction Collaboration System – Final Phase, SPR RB02-008, 2014

This phase of the research project involved two major efforts: (1) Complete the implementation of AEC-Sync (formerly known as Attolist) on the Iowa Falls Arch Bridge project and (2) develop a web-based project management system (WPMS) for projects under $10 million. For the first major effort, AEC-Sync was provided for the Iowa Department of Transportation (DOT) in a software as a service agreement, allowing the Iowa DOT to rapidly implement the solution with modest effort. During the 2010 fiscal year, the research team was able to help with the implementation process for the solution. The research team also collected feedback from the Broadway Viaduct project team members before the start of the project and implementation of the solution. For the 2011 fiscal year, the research team collected the post-project surveys from the Broadway Viaduct project members and compared them to the pre-project survey results. The result of the AEC-Sync implementation in the Broadway Viaduct project was a positive one. The project members were satisfied with the performance of AEC-Sync and how it facilitated document management and transparency. In addition, the research team distributed, collected, and analyzed the pre-project surveys for the Iowa Falls Arch Bridge project. During the 2012 fiscal year, the research team analyzed the post-project surveys for the Iowa Falls Arch Bridge project AEC-Sync implementation and found a positive outcome when compared to the pre-project surveys. The second major effort for this project involved the identification and implementation of a WPMS solution for smaller bridge and highway projects. During the 2011 fiscal year, Microsoft SharePoint was selected to be implemented on these smaller highway projects. In this year, workflows for the shop/working drawings for the smaller highway projects specified in Section 1105 of the Iowa DOT Specifications were developed. These workflows will serve as the guide for the development of the SharePoint pages. In order to implement the Microsoft SharePoint pages, the effort of an integrated team proved to be vital because it brought together the expertise required from researchers, programmers, and webpage developers to develop the SharePoint pages.

Calibration of Highway Safety Manual Work Zone Crash Modification Factors, TPF-5(081), 2014

The Highway Safety Manual is the national safety manual that provides quantitative methods for analyzing highway safety. The HSM presents crash modification factors related to work zone characteristics such as work zone duration and length. These crash modification factors were based on high-impact work zones in California. Therefore there was a need to use work zone and safety data from the Midwest to calibrate these crash modification factors for use in the Midwest. Almost 11,000 Missouri freeway work zones were analyzed to derive a representative and stratified sample of 162 work zones. The 162 work zones was more than four times the number of work zones used in the HSM. This dataset was used for modeling and testing crash modification factors applicable to the Midwest. The dataset contained work zones ranging from 0.76 mile to 9.24 miles and with durations from 16 days to 590 days. A combined fatal/injury/non-injury model produced a R2 fit of 0.9079 and a prediction slope of 0.963. The resulting crash modification factors of 1.01 for duration and 0.58 for length were smaller than the values in the HSM. Two practical application examples illustrate the use of the crash modification factors for comparing alternate work zone setups.

Development of MASH TL-3 Transition Between Guardrail and Portable Concrete Barriers, TPF-5(081), 2014

Often, road construction causes the need to create a work zone. In these scenarios, portable concrete barriers (PCBs) are typically installed to shield workers and equipment from errant vehicles as well as prevent motorists from striking other roadside hazards. For an existing W-beam guardrail system installed adjacent to the roadway and near the work zone, guardrail sections are removed in order to place the portable concrete barrier system. The focus of this research study was to develop a proper stiffness transition between W-beam guardrail and portable concrete barrier systems. This research effort was accomplished through development and refinement of design concepts using computer simulation with LS-DYNA. Several design concepts were simulated, and design metrics were used to evaluate and refine each concept. These concepts were then analyzed and ranked based on feasibility, likelihood of success, and ease of installation. The rankings were presented to the Technical Advisory Committee (TAC) for selection of a preferred design alternative. Next, a Critical Impact Point (CIP) study was conducted, while additional analyses were performed to determine the critical attachment location and a reduced installation length for the portable concrete barriers. Finally, an additional simulation effort was conducted in order to evaluate the safety performance of the transition system under reverse-direction impact scenarios as well as to select the CIP. Recommendations were also provided for conducting a Phase II study and evaluating the nested Midwest Guardrail System (MGS) configuration using three Test Level 3 (TL-3) full-scale crash tests according to the criteria provided in the Manual for Assessing Safety Hardware, as published by the American Association of Safety Highway and Transportation Officials (AASHTO).

State of Iowa Employee Handbook, November 2014

This information is based on Iowa Department of Administrative Services (DAS) rules and policies and does not create an employment contract. Much of the information in this handbook is also covered in the State’s collective bargaining agreements. Where there are differences between a collective bargaining agreement and this handbook, the collective bargaining agreement prevails for employees covered by the agreement. Where there are differences between this handbook and DAS rules and policies, DAS rules and policies prevail.

2014 Registered Flex Fuel Vehicles

Iowa Code section 452A.33(3) requires a report regarding flexible fuel vehicles registered in Iowa. The report includes the number of flexible fuel vehicles according to year of manufacture; the number of passenger vehicles according to year of manufacture; and the number of light pickup trucks according to the year of manufacture.

Imported Cattle Report, September 2014

The Imported Cattle report monthly by the Department of Agricultural.

Imported Cattle Report, October 2014

The Imported Cattle report monthly by the Department of Agricultural.

Imported Cattle Report, November 2014

The Imported Cattle report monthly by the Department of Agricultural.

Imported Cattle Report, December 2014

The Imported Cattle report monthly by the Department of Agricultural.

Other Imported Livestock Report to Iowa, September 2014

The Other Imported Livestock report monthly by the Department of Agricultural.

Other Imported Livestock Report to Iowa, October 2014

The Other Imported Livestock report monthly by the Department of Agricultural.

Other Imported Livestock Report to Iowa, November 2014

The Other Imported Livestock report monthly by the Department of Agricultural.

Other Imported Livestock Report to Iowa, December 2014

The Other Imported Livestock report monthly by the Department of Agricultural.