Iowa Petroleum Underground Storage Tank Board, June 30, 2002

State Agency Audit Report

Iowa Petroleum Underground Storage Tank Board State of Iowa, Independent Auditor's Reports Financial Statements and Supplementary Information, June 30, 2003

State Agency Audit Report

Iowa Petroleum Underground Storage Tank Board, State of Iowa, Independent Auditor's Reports, Financial Statements and Supplementary Information, June 30, 2004

State Audit Reports

Concrete Materials Storage, Mixing and Delivery, November 2004

Proper storage practices are critical to protect materials from intermingling, contamination, or degradation, and to maintain consistent aggregate gradation throughout a project. Concrete Paving Workforce Reference no.1

Iowa Petroleum Underground Storage Tank Board, State of Iowa, Independent Auditor's Reports, Basic Financial Statements and Supplementary Information, Schedule of Findings, June 30, 2005

State Audit Reports

Audit report on the City of Wall Lake, Iowa for the year ended June 30, 2006.

Audit report on the City of Wall Lake, Iowa for the year ended June 30, 2006.

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2006

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2006

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2007

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2007

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2008

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2008

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2009

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2009

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2010

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2010

Task 6: Material Thermal Input for Iowa Materials, May 2008

The present research project was designed to determine thermal properties, such as coefficient of thermal expansion (CTE) and thermal conductivity, of Iowa concrete pavement materials. These properties are required as input values by the Mechanistic-Empirical Pavement Design Guide (MEPDG). In this project, a literature review was conducted to determine the factors that affect thermal properties of concrete and the existing prediction equations for CTE and thermal conductivity of concrete. CTE tests were performed on various lab and field samples of portland cement concrete (PCC) at the Iowa Department of Transportation and Iowa State University. The variations due to the test procedure, the equipment used, and the consistency of field batch materials were evaluated. The test results showed that the CTE variations due to test procedure and batch consistency were less than 5%, and the variation due to the different equipment was less than 15%. Concrete CTE values were significantly affected by different types of coarse aggregate. The CTE values of Iowa concrete made with limestone+graval, quartzite, dolomite, limestone+dolomite, and limestone were 7.27, 6.86, 6.68, 5.83, and 5.69 microstrain/oF (13.08, 12.35, 12.03, 10.50, and 10.25 microstrain/oC), respectively, which were all higher than the default value of 5.50 microstrain/oF in the MEPDG program. The thermal conductivity of a typical Iowa PCC mix and an asphalt cement concrete (ACC) mix (both with limestone as coarse aggregate) were tested at Concrete Technology Laboratory in Skokie, Illinois. The thermal conductivity was 0.77 Btu/hr•ft•oF (1.33 W/m•K) for PCC and 1.21 Btu/hr•ft•oF (2.09 W/m•K) for ACC, which are different from the default values (1.25 Btu/hr•ft•oF or 2.16 W/m•K for PCC and 0.67 Btu/hr•ft•oF or 1.16 W/m•K for ACC) in the MEPDG program. The investigations onto the CTE of ACC and the effects of concrete materials (such as cementitious material and aggregate types) and mix proportions on concrete thermal conductivity are recommended to be considered in future studies.

Material Thermal Inputs of Iowa Materials for MEPDG, 2011

The thermal properties of concrete materials, such as coeffi cient of thermal expansion (CTE), thermal conductivity, and heat capacity, are required by the MEPDG program as the material inputs for pavement design. However, a limited amount of test data is available on the thermal properties of concrete in Iowa. The default values provided by the MEPDG program may not be suitable for Iowa concrete, since aggregate characteristics have signifi cant infl uence on concrete thermal properties.

Audit report on the Iowa Petroleum Underground Storage Tank Board for the year ended June 30, 2011

Audit report on the Iowa Petroleum Underground Storage Tank Board for the year ended June 30, 2011

Audit report on the Iowa Petroleum Underground Storage Tank Board for the year ended June 30, 2012

Audit report on the Iowa Petroleum Underground Storage Tank Board for the year ended June 30, 2012