Improving Transition Outcomes: Council Bluffs Youth Connections: E-Mentoring Replication Template

Replication Template for Improving Transition Outcomes Council Bluffs Youth Connections E-Mentoring Prototype. This concise document will help your community team implement and plan for sustaining e-mentoring.

Improving Transition Outcomes: Henry County Transition Partners: Infrastructure Building Replication Template

Replication Template for Improving Transition Outcomes Henry County Transition Partners Prototype. This concise document will help you build a community team and the infrastructure necessary to implement and plan for sustaining specific initiatives.

Improving Transition Outcomes: CASE (Career And Self Exploration): Replication Template

Replication Template for Improving Transition Outcomes CASE (Career And Self Exploration) Prototype. This concise document explains how your team can implement CASE and the corresponding entrepreneurship component.

Improving Transition Outcomes: Introducing the Prototype Replication Templates

Brief overview of the three community demonstration prototypes established under Improving Transition Outcomes and an introduction to the Replication Templates developed to assist community teams.

Nonlinear Finite Element Study of Piles in Integral Abutment Bridges, HR-227, Part 2, 1982

The highway departments of the states which use integral abutments in bridge design were contacted in order to study the extent of integral abutment use in skewed bridges and to survey the different guidelines used for analysis and design of integral abutments in skewed bridges. The variation in design assumptions and pile orientations among the various states in their approach to the use of integral abutments on skewed bridges is discussed. The problems associated with the treatment of the approach slab, backfill, and pile cap, and the reason for using different pile orientations are summarized in the report. An algorithm based on a state-of-the-art nonlinear finite element procedure previously developed by the authors was modified and used to study the influence of different factors on behavior of piles in integral abutment bridges. An idealized integral abutment was introduced by assuming that the pile is rigidly cast into the pile cap and that the approach slab offers no resistance to lateral thermal expansion. Passive soil and shear resistance of the cap are neglected in design. A 40-foot H pile (HP 10 X 42) in six typical Iowa soils was analyzed for fully restrained pile head and pinned pile head. According to numerical results, the maximum safe length for fully restrained pile head is one-half the maximum safe length for pinned pile head. If the pile head is partially restrained, the maximum safe length will lie between the two limits. The numerical results from an investigation of the effect of predrilled oversized holes indicate that if the length of the predrilled oversized hole is at least 4 feet below the ground, the vertical load-carrying capacity of the H pile is only reduced by 10 percent for 4 inches of lateral displacement in very stiff clay. With no predrilled oversized hole, the pile failed before the 4-inch lateral displacement was reached. Thus, the maximum safe lengths for integral abutment bridges may be increased by predrilling. Four different typical Iowa layered soils were selected and used in this investigation. In certain situations, compacted soil (> 50 blow count in standard penetration tests) is used as fill on top of natural soil. The numerical results showed that the critical conditions will depend on the length of the compacted soil. If the length of the compacted soil exceeds 4 feet, the failure mechanism for the pile is similar to one in a layer of very stiff clay. That is, the vertical load-carrying capacity of the H pile will be greatly reduced as the specified lateral displacement increases.

Design Methodology for Corrugated Metal Pipe Tiedowns, HR-362, Phase II, 1995

This investigation is the final phase of a three part study whose overall objectives were to determine if a restraining force is required to prevent inlet uplift failures in corrugated metal pipe (CMP) installations, and to develop a procedure for calculating the required force when restraint is required. In the initial phase of the study (HR-306), the extent of the uplift problem in Iowa was determined and the forces acting on a CMP were quantified. In the second phase of the study (HR- 332), laboratory and field tests were conducted. Laboratory tests measured the longitudinal stiffness ofCMP and a full scale field test on a 3.05 m (10 ft) diameter CMP with 0.612 m (2 ft) of cover determined the soil-structure interaction in response to uplift forces. Reported herein are the tasks that were completed in the final phase of the study. In this phase, a buried 2.44 m (8 ft) CMP was tested with and without end-restraint and with various configurations of soil at the inlet end of the pipe. A total of four different soil configurations were tested; in all tests the soil cover was constant at 0.61 m (2 ft). Data from these tests were used to verify the finite element analysis model (FEA) that was developed in this phase of the research. Both experiments and analyses indicate that the primary soil contribution to uplift resistance occurs in the foreslope and that depth of soil cover does not affect the required tiedown force. Using the FEA, design charts were developed with which engineers can determine for a given situation if restraint force is required to prevent an uplift failure. If an engineer determines restraint is needed, the design charts provide the magnitude of the required force. The design charts are applicable to six gages of CMP for four flow conditions and two types of soil.

The Relationship of Aggregate Durability to Trace Element Content, Interim Report, HR-266, 1984

This report is a brief overview of the recent Iowa Department of Transportation research in the area of durability of Portland cement, concrete under the direction of Wendeli Dubberke. Present plans are to publish a more detailed report on low Portland cement concrete- durability research in January, 1985.