Retrofit Methods for Distortion Cracking Problems in Plate Girder Bridges, TR-436, 2003

This report is formatted to independently present four individual investigations related to similar web gap fatigue problems. Multiple steel girder bridges commonly exhibit fatigue cracking due to out-of-plane displacement of the web near the diaphragm connections. This fatigue-prone web gap area is typically located in negative moment regions of the girders where the diaphragm stiffener is not attached to the top flange. In the past, the Iowa Department of Transportation has attempted to stop fatigue crack propagation in these steel girder bridges by drilling holes at the crack tips. Other nondestructive retrofits have been tried; in a particular case on a two-girder bridge with floor beams, angles were bolted between the stiffener and top flange. The bolted angle retrofit has failed in the past and may not be a viable solution for diaphragm bridges. The drilled hole retrofit is often only a temporary solution, so a more permanent and effective retrofit is required. A new field retrofit has been developed that involves loosening the bolts in the connection between the diaphragm and the girders. Research on the retrofit has been initiated; however, no long-term studies of the effects of bolt loosening have been performed. The intent of this research is to study the short-term effects of the bolt loosening retrofit on I-beam and channel diaphragm bridges. The research also addressed the development of a continuous remote monitoring system to investigate the bolt loosening retrofit on an X-type diaphragm bridge over a number of months, ensuring that the measured strain and displacement reductions are not affected by time and continuous traffic loading on the bridge. The testing for the first three investigations is based on instrumentation of web gaps in a negative moment region on Iowa Department of Transportation bridges with I-beam, channel, and X-type diaphragms. One bridge of each type was instrumented with strain gages and deflection transducers. Field tests, using loaded trucks of known weight and configuration, were conducted on the bridges with the bolts in the tight condition and after implementing the bolt loosening retrofit to measure the effects of loosening the diaphragm bolts. Long-term data were also collected on the X-diaphragm bridge by a data acquisition system that collected the data continuously under ambient truck loading. The collected data were retrievable by an off-site modem connection to the remote data acquisition system. The data collection features and ruggedness of this system for remote bridge monitoring make it viable as a pilot system for future monitoring projects in Iowa. Results indicate that loosening the diaphragm bolts reduces strain and out-of-plane displacement in the web gap, and that the reduction is not affected over time by traffic or environmental loading on the bridge. Reducing the strain in the web gap allows the bridge to support more cycles of loading before experiencing fatigue, thus increase the service life of the bridge. Two-girder floor beam bridges may also exhibit fatigue cracking in girder webs.

Development of In-Situ Detection Methods for Materials-Related Distress (MRD) in Concrete Pavements, July 2003

The purpose of this research was to summarize existing nondestructive test methods that have the potential to be used to detect materials-related distress (MRD) in concrete pavements. The various nondestructive test methods were then subjected to selection criteria that helped to reduce the size of the list so that specific techniques could be investigated in more detail. The main test methods that were determined to be applicable to this study included two stress-wave propagation techniques (impact-echo and spectral analysis of surface waves techniques), infrared thermography, ground penetrating radar (GPR), and visual inspection. The GPR technique was selected for a preliminary round of “proof of concept” trials. GPR surveys were carried out over a variety of portland cement concrete pavements for this study using two different systems. One of the systems was a state-of-the-art GPR system that allowed data to be collected at highway speeds. The other system was a less sophisticated system that was commercially available. Surveys conducted with both sets of equipment have produced test results capable of identifying subsurface distress in two of the three sites that exhibited internal cracking due to MRD. Both systems failed to detect distress in a single pavement that exhibited extensive cracking. Both systems correctly indicated that the control pavement exhibited negligible evidence of distress. The initial positive results presented here indicate that a more thorough study (incorporating refinements to the system, data collection, and analysis) is needed. Improvements in the results will be dependent upon defining the optimum number and arrangement of GPR antennas to detect the most common problems in Iowa pavements. In addition, refining highfrequency antenna response characteristics will be a crucial step toward providing an optimum GPR system for detecting materialsrelated distress.

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.

Concrete Paving Training & Field Reference for Preventing Common Problems, August 2006

To ensure that high-quality materials are used in concrete mixing, all materials delivered to the site should be inspected to ensure that they meet specification requirements. All materials should be delivered with the proper certifications, invoices, or bill of lading. These records should indicate when the shipment arrived, the amount and identification of material delivered, and the laboratory report certification number, invoice number, and ticket number.

Toolbox to Address Safety and Operations on School Grounds and Public Streets Adjacent to Elementary and Middle Schools in Iowa, August 2006

This study identified transportation safety issues at existing Iowa school sites through on-site observations, traffic data collection, and through interviews with schools, law enforcement, and traffic engineers. Frequently observed problems, such as crossing at unmarked crosswalks, unloading and loading students on the street side, inattentive student safety patrols, and illegal parking, were documented and solutions were recommended for implementation. The results of the study also conclude that regular communications between school officials, traffic engineers, law enforcement, parents, and school transportation personnel are all critical to promoting safe operations within school zones.

Consumer Advisory Bulletin, Fair Debt Collection: Know Your Rights, March 2007

The Attorney General’s Consumer Protection Division receives hundreds of calls and consumer complaints every year. Follow these tips to avoid unexpected expense and disappointments. This record is about: Fair Debt Collection: Know Your Rights

The State of the Judiciary, 2009

Thank you for inviting me again this year to talk with you about the condition of Iowa’s judicial branch. As your partner in government, we look forward to working with you on issues affecting the administration of justice. If I could capture the condition of our courts, indeed the condition of our state, in a few words, it would be: “We live in challenging times.” No one knows the true meaning of this phrase better than those Iowans hit by natural disasters. But my focus today is, of course, on the courts. Ensuring the delivery of equal, affordable and accessible justice is always challenging work, but it will be especially so this year and the next in light of the State’s budget problems. Given the magnitude of this challenge, it is even more imperative that we work together in the spirit of unity, candor and cooperation. And I address you today in this spirit. We are deeply concerned, as you are, about the present financial situation and its effect on individual Iowans. Naturally, we are particularly troubled about its impact on the delivery of justice to our citizens. Even in good economic times, the administration of justice is difficult to fulfill given the sheer volume and complexity of problems Iowans bring to their courthouses. Because of the effects of the nation’s economic downturn, people will need access to justice now more than ever. We already see this happening. The number of mortgage foreclosure cases in Iowa rose 14% in the past year. Debt collection cases increased 20% in the same time. An increase in these types of cases is predictable in tough economic times, but other types of problems may escalate as well. Some experts fear that a recession may also give rise to more crime, child abuse, domestic violence, and substance abuse. Naturally, for the sake of the people who may be harmed by these problems, we hope they do not occur. If they do, however, these matters will demand our immediate attention.

A donde vamos ahora? : (where are we going now) : a report on the problems of the Spanish surnamed and migrant population in Iowa,1970.

This is an overview of the United States Commission on Civil Rights and the duties of the Iowa State Advisory Committee. It contains a report concerning problems of the Spanish surnamed and migrant population in Iowa.

Potential-Scour Assessments and Estimates of Maximum Scour at Selected Bridges in Iowa, HR-344, 1995

This report presents the results of potential-scour assessments at 130 bridges and estimates of maximum scour at 10 bridges, in Iowa. All of the bridges evaluated in the study are constructed bridges (not culverts) that are sites of active or discontinued streamflow-gaging stations and peak-stage measurement sites. The period of the study was from October 1991 to September 1994. The potential-scour assessments were made using a potential-scour index developed by the U.S. Geological Survey for a study in Tennessee. Higher values of the index suggest a greater likelihood of scour-related problems occurring at a bridge. The estimates of maximum scour were made using scour equations recommended by the Federal Highway Administration. In this study, the long term aggradation or degradation that occurred during the period of streamflow data collection at each site was evaluated. Although the abutment-scour equation predicted deep scour holes at many of the sites, the only significant abutment scour that was measured was erosion of the embankment at the left abutment at one bridge after a flood.

Field Data Collection and Reporting Study, HR-377, 1997

A review of the Iowa Department of Transportation's field data collection and reporting system has been performed. Included were several systems used by the Office of Construction and Local Jurisdictions. The entire field data collection and reporting systems for asphalt cement concrete (ACC) paving, portland cement concrete (PCC) paving, and PCC structures were streamlined and computerized. The field procedures for materials acceptance were also reviewed. Best practices were identified and a method was developed to prioritize materials so transportation agencies could focus their efforts on high priority materials. Iowa State University researchers facilitated a discussion about Equal Employment Opportunity (EEO) and Affirmative Action (AA) procedures between the Office of Construction field staff and the Office of Contracts. A set of alternative procedures was developed. Later the Office of Contracts considered these alternatives as they developed new procedures that are currently being implemented. The job close-out package was reviewed and two unnecessary procedures were eliminated. Numerous other procedures were reviewed and flowcharted. Several changes have been recommended that will increase efficiency and allow staff time to be devoted to higher priority activities. It is estimated the improvements in ACC paving, PCC paving and structural concrete will by similar to three full time equivalent (FTE) positions to field construction, field materials and Office of Materials. Elimination of EEO interviews will be equivalent to one FTE position. It is estimated that other miscellaneous changes will be equivalent to at least one other FTE person. This is a total five FTEs. These are conservative estimates based on savings that are easily quantified. It is likely that total positive effect is greater when items that are difficult to quantify are considered.

Pavement Instrumentation, HR-293, 1988

The report documents the development and installation of an instrumented pavement on I-80 in Iowa for the purposes of demonstration and answering current pavement questions. Its two primary objectives include documentation of the installation and verification of existing design procedures through monitoring of the continuous traffic stream reactions in the pavement. Some 120 instruments were installed in a forty foot segment of reconstructed pavement. The instruments included concrete strain gages, weldable strain gages on dowels, LVDT-deflection gages and temperature sensors in the concrete and base material. Five tubes were placed under three joints and two midslabs to measure the relative moisture and density at the interface between the pavement and base with atomic equipment. The instruments were placed ahead of the paving and over 92% of the instruments responded after paving. Planning requirements, problems encountered and costs of installation are presented. The site will use piezoelectric cables in a weigh-in-motion arrangement to trigger the data collection, a microcomputer controlled data acquisition system to analyze multiple sensors simultaneously, and telemetry to monitor the site remotely. Details provide the first time user of instrumentation with valuable information on the planning, problems, costs and coordination required to establish and operate such a site.

Problems of Bridge Supporting and Expansion Devices and an Experimental Comparison of the Dynamic Behavior of Rigid and Elastomeric Bearings, HR-105, 1965

The design of satisfactory supporting and expansion devices for highway bridges is a problem which has concerned bridge design engineers for many years. The problems associated with these devices have been emphasized by the large number of short span bridges required by the current expanded highway program of expressways and interstate highways. The initial objectives of this investigation were: (1) To review and make a field study of devices used for the support of bridge superstructures and for provision of floor expansion; (2) To analyze the forces or factors which influence the design and behavior of supporting devices and floor expansion systems; and (3) To ascertain the need for future research particularly on the problems of obtaining more economical and efficient supporting and expansion devices, and determining maximum allowable distance between such devices. The experimental portion was conducted to evaluate one of the possible simple and economical solutions to the problems observed in the initial portion. The investigation reported herein is divided into four major parts or phases as follows: (1) A review of literature; (2) A survey by questionnaire of design practice of a number of state highway departments and consulting firms; (3) Field observation of existing bridges; and, (4) An experimental comparison of the dynamic behavior of rigid and elastomeric bearings.

Iowa DOT Library Services, Collection, & Technology Assessment, TR-670, 2014

Assesses the impact of library services on research projects, proposes methods to improve the impact of library services on research projects, assesses current library technology systems and proposes upgrades, assesses current library collection infrastructure and propose upgrades, especially in regards to collection damage from water or fire; ascertains patron interest in mobile technologies and suggest development based on interest.

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.

Consumer Advisory: Debt Collections & Debt Collection Scams, February 2015

The Attorney General’s Consumer Protection Division receives hundreds of calls and consumer complaints every year. Follow these tips to avoid unexpected expense and disappointments. This record is about: Tax Time Scams & Tips