Improving Transition Outcomes: CASE (Career And Self Awareness) Prototype: Contact Information

Contact information for the CASE (Career And Self Awareness) prototype.

Dusproportionate Minority Contact in Iowa's Juvenile Justice System, April 2006

This report was developed to provide summary information to allow state agency staff, practitioners and juvenile justice system officials to access a specific section of Iowa’s Three Year Plan. It includes the Disproportionate Minority Contact (DMC) section of Iowa’s 2006 Juvenile Justice and Delinquency Prevention Act formula grant Three-Year Plan. The complete Three Year Plan serves as Iowa’s application for Juvenile Justice and Delinquency Prevention Act formula grant funding.

Pavement Wear and Studded Tire Use in Iowa, HR-148, 1979

This report presents the results of surveys to determine studded tire usage in Iowa. Also reported are the results of measurements of transverse pavement profiles at selected locations where the pavement is subjected to a high volume of traffic. The surveys were made in January of each of the years 1969 through 1978 and in each of 27 areas into which the state was divided. Estimates of studded tire usage were also made at various locations on Interstate highways in Iowa. The lowest percentage of studded tires was observed in the initial count during the winter of 1968-69. Two years later the percentage had increased to the maximum (22.6%) and then began a gradual decline. The latest count in January of 1978 indicated 8.5% of the cars had studded tires. The decline in the use of studded tires is attributed to the efforts of the Iowa DOT and others to obtain a ban on studded tires and a continual increase in the use of radial tires with claims of improved traction. The wear measurements were recorded by camera. It was found that studded tires have worn ruts in Iowa pavements as deep as 5/16 inch. The ruts lead to water on the pavement and this causes hydroplaning, as well as splash and spray. The conclusion of the study was that studded tires should be banned in Iowa.

Fatigue and Residual Stress Investigation of Composite Prestressed Steel Beams, HR-74, 1963

Two composite, prestressed, steel beams, fabricated by slightly different methods, were fatigue tested to destruction. Stresses and deflections were measured at regular intervals, and the behavior of each beam as failure progressed was recorded. Residual stresses were then evaluated by testing segments of each beam. An attempt was made to assess the effects of the residual stresses on fatigue strength.

Dynamics of Highway Bridges, HR-67, 1961

The AASHO specifications for highway bridges require that in designing a bridge, the live load must be multiplied by an impact factor for which a formula is given, dependent only upon the length of the bridge. This formula is a result of August Wohler's tests on fatigue in metals, in which he determined that metals which are subjected to large alternating loads will ultimately fail at lower stresses than those which are subjected only to continuous static loads. It is felt by some investigators that this present impact factor is not realistic, and it is suggested that a consideration of the increased stress due to vibrations caused by vehicles traversing the span would result in a more realistic impact factor than now exists. Since the current highway program requires a large number of bridges to be built, the need for data on dynamic behavior of bridges is apparent. Much excellent material has already been gathered on the subject, but many questions remain unanswered. This work is designed to investigate further a specific corner of that subject, and it is hoped that some useful light may be shed on the subject. Specifically this study hopes to correlate, by experiment on a small scale test bridge, the upper limits of impact utilizing a stationary, oscillating load to represent axle loads moving past a given point. The experiments were performed on a small scale bridge which is located in the basement of the Iowa Engineering Experiment Station. The bridge is a 25 foot simply supported span, 10 feet wide, supported by four beams with a composite concrete slab. It is assumed that the magnitude of the predominant forcing function is the same as the magnitude of the dynamic force produced by a smoothly rolling load, which has a frequency determined by the passage of axles. The frequency of passage of axles is defined as the speed of the vehicle divided by the axle spacing. Factors affecting the response of the bridge to this forcing function are the bridge stiffness and mass, which determine the natural frequency, and the effects of solid damping due to internal structural energy dissipation.

Fatigue Behavior of Air-Entrained Concrete, HR-183, 1977

When a material fails under a number of repeated loads, each smaller than the ultimate static strength, a fatigue failure is said to have taken place. Many studies have been made to characterize the fatigue behavior of various engineering materials. The results of some of these studies have proved invaluable in the evaluation and prediction of the fatigue strength of structural materials. Considerable time and effort has gone into the evaluation of the fatigue behavior of metals. These early studies were motivated by practical considerations: The first fatigue tests were performed on materials that had been observed to fail after repeated loading of a magnitude less than that required for failure under the application of a single load. Mine-hoist chains, railway axles, and steam engine parts were among the first structural components to be recognized as exhibiting fatigue behavior. Since concrete is usually subjected to static loading rather than cyclic loading, need for knowledge of the fatigue behavior of concrete has lagged behind that of metals. One notable exception to this, however, is in the area of highway and airfield pavement design. Due to the fact that the fatigue behavior of concrete must be understood in the design of pavements and reinforced concrete bridges, highway engineers have provided the motivation for concrete fatigue studies since the 1920's.

Fatigue Behavior of Air-Entrained Concrete: Phase II, HR-197, 1979

When a material fails under a number of repeated loads, each smaller than the ultimate static strength, a fatigue failure is said to have taken place. Many studies have been made to characterize the fatigue behavior of various engineering materials. The results of some of these studies have proved invaluable in the evaluation and prediction of the fatigue strength of structural materials. Considerable time and effort have gone into the evaluation of the fatigue behavior of metals. These early studies were motivated by practical considerations: the first fatigue tests were performed on materials that had been observed to fail after repeated loading of a magnitude less than that required for failure under the application of a single load. Mine-hoist chains (1829), railway axles (1852), and steam engine parts were among the first structural components to be recognized as exhibiting fatigue behavior. Since concrete is usually subjected to static loading rather than cyclic loading, need for knowledge of the fatigue behavior of concrete has lagged behind that of metals. One notable exception to this, however, is in the area of highway and airfield pavement design. Due to the fact that the fatigue behavior of concrete must be understood in the design of pavements and reinforced concrete bridges, highway engineers have provided the motivation for concrete fatigue studies since the 1920s.

The Flexural Fatigue Strength of Prestressed Steel I-Beams, HR-73, 1962

The purpose of this investigation was to study the flexural fatigue strength of two prestressed steel I-beams which had previously been fabricated in connection with a jointly sponsored project under the auspices of the Iowa State Highway Commission. The beams were prestressed by deflecting them under the action of a concentrated load at the center of a simple span, then welding unstressed high strength steel plates to the top and bottom flanges to retain a predetermined amount of prestress. The beams were rolled sections of A36 steel and the plates were USS "T-1" steel. Each of the two test specimens were subjected to an identical repeated loading until a fatigue failure occurred. The loading was designed to produce stresses equivalent to those which would have occurred in a simulated bridge and amounted to 84 percent of a standard H-15 live load including impact. One of the beams sustained 2,469,100 repetitions of load to failure and the other sustained 2,756,100 cycles. Following the fatigue tests, an experimental study was made to determine the state of stress that had been retained in the prestressed steel beams. This information, upon which the calculated stresses of the test could be superimposed, provided a method of correlating the fatigue strength of the beams with the fatigue information available on the two steels involved.

Update Regarding Disproportionate Minority Contact (DMC) Progress of Iowa Communities, December 1, 2015

The Iowa State Court Administrator’s Office (SCA) created the CASP Advisory Committee in October 2013 to develop a state plan addressing disproportionate minority contact (DMC) in the juvenile justice system. The planning was assisted with a discretionary grant awarded from the federal Office of Juvenile Justice and Delinquency Prevention (OJJDP).

A Continuous Span Aluminum Girder Concrete Deck Bridge - Part 2 of 2: Fatigue Tests of Aluminum Girders, Final Report, 1997

In 1957, the Iowa State Highway Commission, with financial assistance from the aluminum industry, constructed a 220-ft (67-m) long, four-span continuous, aluminum girder bridge to carry traffic on Clive Road (86th Street) over Interstate 80 near Des Moines, Iowa. The bridge had four, welded I-shape girders that were fabricated in pairs with welded diaphragms between an exterior and an interior girder. The interior diaphragms between the girder pairs were bolted to girder brackets. A composite, reinforced concrete deck served as the roadway surface. The bridge, which had performed successfully for about 35 years of service, was removed in the fall of 1993 to make way for an interchange at the same location. Prior to the bridge demolition, load tests were conducted to monitor girder and diaphragm bending strains and deflections in the northern end span. Fatigue testing of the aluminum girders that were removed from the end spans were conducted by applying constant-amplitude, cyclic loads. These tests established the fatigue strength of an existing, welded, flange-splice detail and added, welded, flange-cover plates and horizontal web plate attachment details. This part, Part 2, of the final report focuses on the fatigue tests of the aluminum girder sections that were removed from the bridge and on the analysis of the experimental data to establish the fatigue strength of full-size specimens. Seventeen fatigue fractures that were classified as Category E weld details developed in the seven girder test specimens. Linear regression analyses of the fatigue test results established both nominal and experimental stress-range versus load cycle relationships (SN curves) for the fatigue strength of fillet-welded connections. The nominal strength SN curve obtained by this research essentially matched the SN curve for Category E aluminum weldments given in the AASHTO LRFD specifications. All of the Category E fatigue fractures that developed in the girder test specimens satisfied the allowable SN relationship specified by the fatigue provisions of the Aluminum Association. The lower-bound strength line that was set at two standard deviations below the least squares regression line through the fatigue fracture data points related well with the Aluminum Association SN curve. The results from the experimental tests of this research have provided additional information regarding behavioral characteristics of full-size, aluminum members and have confirmed that aluminum has the strength properties needed for highway bridge girders.