Automated Traffic/Truck Weight Monitoring Equipment (Weigh-in-Motion), HR-282, 1988

This report documents work undertaken in the demonstration of a low-cost Automatic Weight and Classification System (AWACS). An AWACS procurement specification and details of the results of the project are also included. The intent of the project is to support and encourage transferring research knowledge to state and local agencies and manufacturers through field demonstrations. Presently available, Weigh-in-Motion and Classification Systems are typically too expensive to permit the wide deployment necessary to obtain representative vehicle data. Piezo electric technology has been used in the United Kingdom and Europe and is believed to be the basic element in a low-cost AWACS. Low-cost systems have been installed at two sites, one in Portland Cement Concrete (PCC) pavement in Iowa and the other in Asphaltic Cement Concrete (ACC) pavement in Minnesota to provide experience with both types of pavement. The systems provide axle weights, gross vehicle weight, axle spacing, vehicle classification, vehicle speed, vehicle count, and time of arrival. In addition, system self-calibration and a method to predict contact tire pressure is included in the system design. The study has shown that in the PCC pavement, the AWACS is capable of meeting the needs of state and federal highway agencies, producing accuracies comparable to many current commercial WIM devices. This is being achieved at a procurement cost of substantially less than currently available equipment. In the ACC pavement the accuracies were less than those observed in the PCC pavement which is concluded to result from a low pavement rigidity at this site. Further work is needed to assess the AWACS performance at a range of sites in ACC pavements.

Soil compaction due to forest harvest operations

The objective of this work was to determine, through the use of the bearing capacity model, the traffic effects of the forest harvest operations on the preconsolidation pressure (sigmap), during one cycle of the eucalyptus plantation. The work was conducted using undisturbed soil samples, collected at the surface of the A horizon and in the top of the B horizon of an Udult (PA), Aquox (FX) and Udox (LA) soils. The undisturbed soil samples were used in the uniaxial compression tests. The soil sampling was done before and after the harvest operations. The operations performed with the Forwarder caused greater soil compaction than the ones done with the Feller Büncher and Harvester. The percentage of soil samples, in the region with additional soil compaction, indicated that the Udult was the soil class more susceptible to soil compaction, followed by the Aquox and Udox. Despite Udult is the more susceptible to soil compaction, the regeneration of the soil structure in this soil class was more efficient than in Aquox. The percentage of soil samples with sigmap values in the region with additional soil compaction in 1996, 1998 and 2004, after harvest operations, indicated a sustainable forest exploration in this period.

Pre-harvest soil acidification, liming or N fertilization did not significantly affect the survival and growth of young Norway spruce

Abstract

Trends in Iowa Wildlife Populations and Harvest 2010, October 2011

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2011, October 2012

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2012, October 2013

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2013, December 2014

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2001, October 2002

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2002, September 2003

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2003, December 2004

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2004, October 2005

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2005, December 2006

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2006, December 2007

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2007, September 2008

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.

Trends in Iowa Wildlife Populations and Harvest 2008, September 2009

A report by the Iowa Department of Natural Resources on the trends of Iowa wildlife populations and harvest.