Transverse Joint Sealing with Improved Sealers, HR-276, 1991

Concern about premature joint sealant failures occurring in portland cement concrete (PCC) pavements gave impetus to initiating this research project. Eight sealants, including three silicone sealants, were evaluated and tested in the lab as well as incorporated in approximately 700 joints in the field and evaluated over a six-year period. The preliminary data show that among the silicone sealants, Dow Corning 888 rated the highest. However, this was rated third overall behind the W. R. Meadows cold-applied Sof Seal and Crafco #231 hot pour sealants. The W. R. Meadows and Crafco sealants cost approximately 30 percent and 50 percent less to furnish and place than the Dow Corning product. All joint sealants will continue to be evaluated.

Pressure Relief and Other Joint Rehabilitation Techniques, HR-1042, 1987

A study of four major concrete pavement joint rehabilitation techniques has been conducted, including: pressure relief joints, full-depth repairs, partial-depth repairs and joint resealing. The products of this research include the following for each technique: a summary of published research, detailed documentation of the design and performance of the 36 projects, conclusions and recommendations of the state highway engineers panel, "Design and Construction Guidelines" and "Guide Specifications." The latter two products are prepared for use by state highway agencies. The results of this study are based upon a review of literature, extensive field surveys and analysis of 36 rehabilitation projects, and the experience of an expert panel of state highway engineers.

Longitudinal Joint Forming in PCC Pavements, MLR-00-05, Construction Report, 2003

In conventional construction practices, a longitudinal joint is sawed in a PCC (Portland Cement Concrete) pavement to control concrete shrinkage cracking between two lanes of traffic. Sawing a joint in hardened concrete is an expensive and time consuming operation. The longitudinal joint is not a working joint (in comparison to a transverse joint) as it is typically tied with a tie bar at 30 inch spacing. The open joint reservoir, left by the saw blade, typically is filled or sealed with a durable crack sealant to keep incompressibles and water from getting into the joint reservoir. An experimental joint forming knife has been developed. It is installed under the paving machine to form the longitudinal joint in the wet concrete as a part of the paving process. Through this research method, forming a very narrow longitudinal joint during the paving process, two conventional paving operations can be eliminated. Joint forming eliminates the need of the joint sawing operation in the hard concrete, and as the joint that is formed does not leave a wide-open reservoir, but only a hairline crack, it does not need the joint filling or sealing operation. Therefore, the two conventional longitudinal joint sawing and sealing operations are both being eliminated by this innovation. A laboratory scale prototype joint forming knife was built and tested, initially forming joints in small concrete beams. The results were positive so the method was proposed for field testing. Initial field tests were done in the construction season of 2001, limited to one paving contractor. A number of modifications were made to the knife throughout the field tests. About 3000 feet of longitudinal joint was formed in 2001. Additional testing was done in the 2002 construction season, working with the same contractor. About 150,000 feet of longitudinal joint was formed in 2002. Evaluations of the formed joints were done to determine longitudinal joint hairline crack development rate and appearance. Additional tests will be done in the next construction season to improve or perfect the longitudinal joint forming technique.

Evaluation of Transverse Joint Forming Methods for PCC Pavement, TR-532, 2006

The members of the Iowa Concrete Paving Association, the National Concrete Pavement Technology Center Research Committee, and the Iowa Highway Research Board commissioned a study to examine alternative ways of developing transverse joints in portland cement concrete pavements. The present study investigated six separate variations of vertical metal strips placed above and below the dowels in conventional baskets. In addition, the study investigated existing patented assemblies and a new assembly developed in Spain and used in Australia. The metal assemblies were placed in a new pavement and allowed to stay in place for 30 days before the Iowa Department of Transportation staff terminated the test by directing the contractor to saw and seal the joints. This report describes the design, construction, testing, and conclusions of the project.

Preformed Phoenix Ethylene Propylene Diene Monomer (EPDM) Compression Joint Seals, MLR-93-02, 1999

There is an ongoing drive towards improvements and achieving success in effective and long term sealing of portland cement concrete pavement contraction joints. A variety of joint sealing products and procedures have been applied in Iowa in search of improvements in seal performance. Hot poured rubberized asphalt products were mainly used for sealing all joints in earlier years for highways. In the 1980s, silicone sealant products were becoming popular, especially for the major highways. As a high level of sealant performance was not achieved from silicones in Iowa conditions, other sealing products were tried. Preformed neoprene compression seals are being tried as a substitution for silicone sealants. Due to high costs of materials and installation with neoprene seals, the search for improvements through other joint sealing products and procedures continued. An agreement was made with Phoenix, North America, Inc., to provide and install preformed Ethylene Propylene Diene Monomer (EPDM) compression joint seals. The research site was a 600 ft (183 m) test section of northbound I-29 in Pottawattamie County, Iowa. Seal installation was done August 20, 1992. Seal performance has been good over the past seven years and the seals are still showing no significant signs of decreasing performance.

Audit report on the Iowa Water Pollution Control Works Financing Program (Clean Water Program) and the Iowa Drinking Water Facilities Financing Program (Drinking Water Program), joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources, for the year ended June 30, 2005

Audit report on the Iowa Water Pollution Control Works Financing Program (Clean Water Program) and the Iowa Drinking Water Facilities Financing Program (Drinking Water Program), joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources, for the year ended June 30, 2005

Audit report on the Iowa Water Pollution Control Works Financing Program (Clean Water Program) and the Iowa Drinking Water Facilities Financing Program (Drinking Water Program), joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources, for the year ended June 30, 2004

Audit report on the Iowa Water Pollution Control Works Financing Program (Clean Water Program) and the Iowa Drinking Water Facilities Financing Program (Drinking Water Program), joint programs of the Iowa Finance Authority and the Iowa Department of Natural Resources, for the year ended June 30, 2004

Joint Enrollment 2012

This report summarizes joint enrollment in Iowa's community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. This report contains fiscal year data for the state's 15 community colleges reported through the Community College Management Information System (MIS) and confirmed by each college.

Joint Enrollment 2008

This report summarizes joint enrollment in Iowa's community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. This report contains fiscal year data for the state's 15 community colleges reported through the Community College Management Information System (MIS) and confirmed by each college.

Joint Enrollment Report, 2009

The Iowa Department of Education collects information on joint enrollment in Iowa’s 15 community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. Most jointly enrolled students enroll through Senior Year Plus programs such as PSEO (Postsecondary Enrollment Options) and concurrent enrollment. Others enroll independently by paying tuition or enrolling in courses delivered through contractual agreements that do not meet the definition of concurrent enrollment. For more information about Senior Year Plus programs, please refer to the department’s website. This report consists of fiscal year and trend data on joint enrollment including headcount enrollment, credit hours, student demographics, and enrollment by program type and offering arrangement. All data included in this report is taken from the Community College Management Information System (MIS) and confirmed by each college, unless otherwise noted.

Joint Enrollment 2010

This report summarizes joint enrollment in Iowa's community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. This report contains fiscal year data for the state's 15 community colleges reported through the Community College Management Information System (MIS) and confirmed by each college.

Joint Enrollment 2013

This report summarizes joint enrollment in Iowa's community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. This report contains fiscal year data for the state's 15 community colleges reported through the Community College Management Information System (MIS) and confirmed by each college.

Joint Enrollment 2014

This report summarizes joint enrollment in Iowa's community colleges. Jointly enrolled students are high school students enrolled in community college credit coursework. This report contains fiscal year data for the state's 15 community colleges reported through the Community College Management Information System (MIS) and confirmed by each college.

05036-013 Joint Drainage District 1-10 Fnial Report

Install new tile system to eliminate the use of 20 agricultural drainage wells (ADW) that have been ruled by EPA to be "vunerable to spills from manure lagoons, direct discharges from septic tanks and accidental releases of materails used in farming". The project includes a tile system that will provide an outlet for all the tile connected to the ADWs and close all 20 ADWs in the drainage district. The pipe ranges in size from 42" to 8" in diameter and approximately 48,000 lineal feet to be installed.

1199-000 Soil Nutrient Mass Balance Study

Key Points: • Iowa’s exceptional agricultural productivity is dependent upon nutrient‐rich soils with high carbon and nitrogen stocks. • Soil carbon and nitrogen stocks in Iowa corn‐soybean rotations are at significant risk of long‐term decline. • Soil carbon and nitrogen stocks are a function of crop residue inputs. • Nutrient input levels that do not maximize crop yield and residue production are likely to reduce soil carbon and nitrogen stocks. • If soil carbon and nitrogen stocks decline, water quality improvements become more difficult. • Soil carbon and nitrogen balances are extremely difficult to measure, but positive balances are essential to the future of Iowa agriculture. Recommended Actions: • Accurate measurement of soil carbon and nitrogen balances is exceptionally difficult, but can be accomplished with sufficient investment and long‐term planning. • The ideal approach will include a combination of measurements from farms and experimental networks that manipulate nutrient inputs. • With proper planning and cooperation, Iowa State University and the Iowa Department of Agriculture and Land Stewardship can address the concerns raised in this report regarding the future of Iowa’s soil resource and agricultural productivity.