Iowa Department of Transportation Major Items - Preliminary Quantity Report, November 15, 2011; With Addendums

Weekly letting report.

Iowa Department of Transportation Major Items - Preliminary Quantity Report, December 20, 2011; With Addendums

Weekly letting report.

Bond Development in Concrete Overlays, August 1995

Data collection to determine the rate of bond strength development between concrete overlays and existing pavements and the evaluation of nondestructive testing methods for determining concrete strength were the objectives of this study. Maturity meters and pulse velocity meters were employed to determine the rate of flexural strength gain and determine the time for opening of newly constructed pavements to traffic. Maturity measurements appear to provide a less destructive method of testing. Pulse velocity measurements do require care in the preparation of the test wells and operator care in testing. Both devices functioned well under adverse weather and construction conditions and can reduce construction traffic delay decisions. Deflection testing and strain gaging indicate differences in the reaction of the overlay and existing pavement under grouting versus nongrouted sections. Grouting did enhance the rate of bond development with Type I11 cement out performing the Type I1 grout section. Type I11 and Type I1 cement grouts enhanced resistance to cracking in uniformly supported pavements where joints are prepared prior to overlays achieving target flexural strengths. Torsional and direct shear testing provide additional ways of measuring bond development at different cure times. Detailed data analysis will be utilized by TRANSTEC, Inc. to develop a bonded overlay construction guidelines report.

Iowa Department of Transportation Major Items - Preliminary Quantity Report, January 18, 2012; With Addendums

Weekly letting report.

Iowa Department of Transportation Major Items - Preliminary Quantity Report, February 21, 2012; With Addendums

Weekly letting report.

Measuring effective electroweak couplings in single top production at the CERN LHC

s out to be more relevant than naively expected, is retained. Finally we analyze different aspects of the total cross section relevant to the measurement of new physics through the effective couplings. The above analysis also applies to top antiquark production in a straightforward way.

Iowa Department of Transportation Fiscal Year 2011 Report of Savings by Using Video Conferencing Through Iowa Communications Network to the Iowa General Assembly

Iowa Code section 8D.10 requires certain state agencies prepare an annual report to the General Assembly certifying the identified savings associated with that state agency’s use of the Iowa Communications Network (ICN). This report covers estimated cost savings related to video conferencing via ICN for the Iowa Department of Transportation (Iowa DOT). In fiscal year 2011, the Iowa DOT did not conduct any sessions utilizing ICN’s video conferencing system, therefore, no cost savings were calculated for this report.

Public Transportation Takes Us There, June 23, 2011

Document produced by Iowa Department of Transportation about Public Transportation in Iowa.

An improved method for measuring soil microbial activity by gas phase flow injection analysis

The rate of carbon dioxide production is commonly used as a measure of microbial activity in the soil. The traditional method of CO2 determination involves trapping CO2 in an alkali solution and then determining CO2 concentration indirectly by titration of the remaining alkali in the solution. This method is still commonly employed in laboratories throughout the world due to its relative simplicity and the fact that it does not require expensive, specific equipment. However, there are several drawbacks: the method is time-consuming, requires large amounts of chemicals and the consistency of results depends on the operator's skills. With this in mind, an improved method was developed to analyze CO2 captured in alkali traps, which is cheap and relatively simple, with a substantially shorter sample handling time and reproducibility equivalent to the traditional titration method. A comparison of the concentration values determined by gas phase flow injection analysis (GPFIA) and titration showed no significant difference (p > 0.05), but GPFIA has the advantage that only a tenth of the sample volume of the titration method is required. The GPFIA system does not require the purchase of new, costly equipment but the device was constructed from items commonly found in laboratories, with suggestions for alternative configurations for other detection units. Furthermore, GPFIA for CO2 analysis can be equally applied to samples obtained from either the headspace of microcosms or from a sampling chamber that allows CO2 to be released from alkali trapping solutions. The optimised GPFIA method was applied to analyse CO2 released from degrading hydrocarbons from a site contaminated by diesel spillage.

State of Iowa Transportation Map, 2011

This document is the State Map of Iowa, both front and back of the year in the title. All maps were are in pdf format and can be used as a historical reference.

2009 Iowa Transportation Map for Bicyclists, 2009

This online Adobe Portable Document Format (PDF) version of the 2009 Iowa Transportation Map for Bicyclists was developed using the same electronic files that were used to create the widely distributed paper version of the map. The files have been translated to allow access for the viewing customers while still maintaining the detail necessary to display the map content. The PDF conversion utility from Adobe compressed the 75MB main map image file down to a 4.2MB file. This 4.2MB file may still take time to download so please be patient. We believe the end result is well worth the wait. The city detail maps are much smaller and will download more quickly.

Iowa Department of Transportation Office of Contracts Letting Summary July 1, 2010 through June 30, 2011

Twelve regularly scheduled lettings and three emergency/special lettings were held by the Iowa Department of Transportation for construction and maintenance work during the period covered by this report. At these lettings, projects totally $741,289,234 were approved.