Methamphetamine Inhibitor: Calcium Nitrate– What You Need to Know, 2006

Iowa agriculture depends on anhydrous ammonia as a low-cost form of nitrogen fertilizer on 61 percent of Iowa’s 12.4 million acres of corn. Now we find a threat to that source of nutrient—the theft of anhydrous ammonia for use in making a powerful, illegal narcotic called methamphetamine. Naturally, the fertilizer industry is outraged by the illegal and illicit use of our products. We want to play a role in preventing abuse in the future. By raising awareness, knowing how to respond and using the Meth Inhibitor, fertilizer dealers can assist law enforcement in combating this illicit use of a product important to Iowa farmers.

Application of Visualization and Simulation Program to Improve Work Zone Safety and Mobility, January 2010

A previous study sponsored by the Smart Work Zone Deployment Initiative, “Feasibility of Visualization and Simulation Applications to Improve Work Zone Safety and Mobility,” demonstrated the feasibility of combining readily available, inexpensive software programs, such as SketchUp and Google Earth, with standard two-dimensional civil engineering design programs, such as MicroStation, to create animations of construction work zones. The animations reflect changes in work zone configurations as the project progresses, representing an opportunity to visually present complex information to drivers, construction workers, agency personnel, and the general public. The purpose of this study is to continue the work from the previous study to determine the added value and resource demands created by including more complex data, specifically traffic volume, movement, and vehicle type. This report describes the changes that were made to the simulation, including incorporating additional data and converting the simulation from a desktop application to a web application.

HR-243 Production and Evaluation of Calcium Magnesium Acetate, Febrauray 19, 2001

Calcium magnesium acetate (CMA) has been identified by Bjorksten Research Laboratories as an environmentally harmless alternative to sodium or calcium chloride for deicing highways. Their study found CMA to be noncorrosive to steel, aluminum and zinc with little or no anticipated environmental impact. When used, it degrades into elements found in abundance in nature. The deicing capabilities were found to be similar to sodium chloride. The neutralized CMA they produced did cause scaling of PC concrete, but they did not expect mildly alkaline CMA to have this effect. In the initial investigation of CMA at the Iowa DOT laboratory, it was found that CMA produced from hydrated lime and acetic acid was a light, fluffy material. It was recognized that a deicer in this form would be difficult to effectively distribute on highways without considerable wind loss. A process was developed to produce CMA in the presence of sand to increase particle weight. In this report the product of this process, which consists of sand particles coated with CMA, is referred to as "CMA deicer". The mixture of salts, calcium magnesium acetate, is referred to as "CMA". The major problems with CMA for deicing are: (1) it is not commercially available, (2) it is expensive with present production methods and (3) there is very little known about how it performs on highways under actual deicing conditions. In view of the potential benefits this material offers, it is highly desirable to find solutions or answers to these problems. This study provides information to advance that effort.

Production and Evaluation of Calcium Magnesium Acetate, HR-243, 1982

Calcium magnesium acetate (CMA) has been identified by Bjorksten Research Laboratories as an environmentally harmless alternative to sodium or calcium chloride for deicing highways. Their study found CMA to be noncorrosive to steel, aluminum and zinc with little or no anticipated environmental impact. When used, it degrades into elements found in abundance in nature. The deicing capabilities were found to be similar to sodium chloride. The neutralized CMA they produced did cause scaling of PC concrete, but they did not expect mildly alkaline CMA to have this effect. In the initial investigation of CMA at the Iowa DOT laboratory, it was found that CMA produced from hydrated lime and acetic acid was a light, fluffy material. It was recognized that a deicer in this form would be difficult to effectively distribute on highways without considerable wind loss. A process was developed to produce CMA in the presence of sand to increase particle weight. In this report the product of this process, which consists of sand particles coated with CMA, is referred to as "CMA deicer". The mixture of salts, calcium magnesium acetate, is referred to as "CMA". The major problems with CMA for deicing are: (1) it is not commercially available, (2) it is expensive with present production methods and (3) there is very little known about how it performs on highways under actual deicing conditions. In view of the potential benefits this material offers, it is highly desirable to find solutions or answers to these problems. This study provides information to advance that effort. The study consisted of four principal tasks which were: 1. Production of CMA Deicer The objective was to further develop the laboratory process for producing CMA deicer on a pilot plant basis and to produce a sufficient quantity for field trials. The original proposal called for producing 20 tons of CMA deicer. 2. Field Evaluation of CMA Deicer The objective was to evaluate the effectiveness of CMA deicer when used under field conditions and obtain information on application procedures. Performance was compared with a regular 50/50 mixture of sand and sodium chloride. 3. Investigation of Effects of CMA on PC Concrete The objective was to determine any scaling effect that mildly alkaline CMA might have on PC concrete. Comparison was made with calcium chloride. 4. Determine Feasibility of Producing High Magnesium CMA The objective was to investigate the possibility of producing a CMA deicer with magnesium acetate content well above that produced from dolomitic lime. A high magnesium acetate content is desirable because pure magnesium acetate has a water eutectic of -22 F° as compared with +5 F° for calcium acetate and is therefore a more effective deicer.

Experimental Use of Calcium Magnesium Acetate, HR-253, 1983

The Iowa Department of Transportation Materials Laboratory personnel announced in early 1982 a process to produce a road deicer consisting of sand grains coated with calcium magnesium acetate (CMA). From that point forward the Iowa DOT began searching for a means of economically producing CMA to their concept. During 1983 and 1984 the first attempts devised for commercially producing CMA were attempted by the W.G. Block Company, Davenport, Iowa, under Iowa Highway Research Board Project HR-253. This first attempt at commercially producing CMA was accomplished by the use of concrete transit mixer equipment. Even though this procedure proved successful in the batch mixing of CMA, the need for higher production rates to reduce the cost per ton still existed. During the fall of 1984, Cedarapids Inc, Cedar Rapids, Iowa, proposed to Iowa DOT personnel the application of their technology to a continuous mixing concept for CMA. Arrangements were made for the continuous test mixing of 60 to 100 tons of CMA/sand deicer. This report covers the production effort, description and results of procedures outlined in Cedarapids Inc's proposal of September 19, 1984. The objectives of this research were: 1. To produce the CMA/sand deicer concept on a continuous mixing basis to Iowa DOT CMA concentration levels. 2. To evaluate the results of preheating the carrying vehicle (sand) prior to CMA ingredient introduction. 3. To analyze the feasibility of production equipment and procedures necessary for portable and/or stationary applications of continuous mixing concepts.

Evaluation of Calcium Magnesium Acetate Deicer in Scott County, HR-253, Progress Report, 1987

The field testing of the noncorrosive alternative deicing agent, calcium magnesium acetate is described. Seventy three tons were produced of one part CMA and three parts sand deicer which was field tested on I-280 from I-80 to the Mississippi River (7,000 ADT with 50% trucks). A comparative application was made with one part sand and one part sodium chloride. The study found that CMA deicer required a longer time for the pavement to reach normal conditions, and 20-25% more CMA deicer to provide the desired deicing. It was concluded that the CMA deicer was not as dependable as the sodium chloride deicing agent, and it was more difficult to clean up the equipment for spreading the CMA deicer.

Experimental Use of Calcium Magnesium Acetate, Addendum, HR-253, 1984

The Iowa Department of Transportation Materials Laboratory personnel developed a process to produce a road deicer consisting of sand grains coated with calcium magnesium acetate (CMA). Research project HR-253 was established to explore commercial production of the CMA/sand deicer by an independent contractor. About 60 tons of the deicer was produced at a ready-mix concrete facility and evaluated in the field during the 1983-1984 winter season. The initial contracted production of CMA/sand deicer under research project HR-253 identified two major problems: (1) excessive unreacted lime in the final product, and (2) formation of spherical lumps within the product requiring subsequent size reduction. It was recommended in the HR-253 report that additional deicer be produced as a continuation of the project in order to address these problems and further develop the production process. A contract was negotiated with W. G. Block Co. to produce and deliver 50 tons of additional deicer. This addendum report covers this production effort including descriptions and results of all modifications of equipment and process procedures used.

Simulation and Analysis of Arterial Traffic Operations Along the U.S. 61 Corridor in Burlington, Iowa, 1998

The Center for Transportation Research and Education (CTRE) used the traffic simulation model CORSIM to access proposed capacity and safety improvement strategies for the U.S. 61 corridor through Burlington, Iowa. The comparison between the base and alternative models allow for evaluation of the traffic flow performance under the existing conditions as well as other design scenarios. The models also provide visualization of performance for interpretation by technical staff, public policy makers, and the public. The objectives of this project are to evaluate the use of traffic simulation models for future use by the Iowa Department of Transportation (DOT) and to develop procedures for employing simulation modeling to conduct the analysis of alternative designs. This report presents both the findings of the U.S. 61 evaluation and an overview of model development procedures. The first part of the report includes the simulation modeling development procedures. The simulation analysis is illustrated through the Burlington U.S. 61 corridor case study application. Part I is not intended to be a user manual but simply introductory guidelines for traffic simulation modeling. Part II of the report evaluates the proposed improvement concepts in a side by side comparison of the base and alternative models.

Economics of Using Calcium Chloride vs. Sodium Chloride for Deicing/Anti-Icing, TR-488, 2008

The use of chemicals is a critical part of a pro-active winter maintenance program. However, ensuring that the correct chemicals are used is a challenge. On the one hand, budgets are limited, and thus price of chemicals is a major concern. On the other, performance of chemicals, especially at lower pavement temperatures, is not always assured. Two chemicals that are used extensively by the Iowa Department of Transportation (Iowa DOT) are sodium chloride (or salt) and calcium chloride. While calcium chloride can be effective at much lower temperatures than salt, it is also considerably more expensive. Costs for a gallon of salt brine are typically in the range of $0.05 to $0.10, whereas calcium chloride brine may cost in the range of $1.00 or more per gallon. These costs are of course subject to market forces and will thus change from year to year. The idea of mixing different winter maintenance chemicals is by no means new, and in general discussions it appears that many winter maintenance personnel have from time to time mixed up a jar of chemicals and done some work around the yard to see whether or not their new mix “works.” There are many stories about the mixture turning to “mayonnaise” (or, more colorfully, to “snot”) suggesting that mixing chemicals may give rise to some problems most likely due to precipitation. Further, the question of what constitutes a mixture “working” in this context is a topic of considerable discussion. In this study, mixtures of salt brine and calcium chloride brine were examined to determine their ice melting capability and their freezing point. Using the results from these tests, a linear interpolation model of the ice melting capability of mixtures of the two brines has been developed. Using a criterion based upon the ability of the mixture to melt a certain thickness of ice or snow (expressed as a thickness of melt-water equivalent), the model was extended to develop a material cost per lane mile for the full range of possible mixtures as a function of temperature. This allowed for a comparison of the performance of the various mixtures. From the point of view of melting capacity, mixing calcium chloride brine with salt brine appears to be effective only at very low temperatures (around 0° F and below). However, the approach described herein only considers the material costs, and does not consider application costs or other aspects of the mixture performance than melting capacity. While a unit quantity of calcium chloride is considerably more expensive than a unit quantity of sodium chloride, it also melts considerably more ice. In other words, to achieve the same result, much less calcium chloride brine is required than sodium chloride brine. This is important in considering application costs, because it means that a single application vehicle (for example, a brine dispensing trailer towed behind a snowplow) can cover many more lane miles with calcium chloride brine than with salt brine before needing to refill. Calculating exactly how much could be saved in application costs requires an optimization of routes used in the application of liquids in anti-icing, which is beyond the scope of the current study. However, this may be an area that agencies wish to pursue for future investigation. In discussion with winter maintenance personnel who use mixtures of sodium chloride and calcium chloride, it is evident that one reason for this is because the mixture is much more persistent (i.e. it stays longer on the road surface) than straight salt brine. Operationally this persistence is very valuable, but at present there are not any established methods to measure the persistence of a chemical on a pavement. In conclusion, the study presents a method that allows an agency to determine the material costs of using various mixtures of salt brine and calcium chloride brine. The method is based upon the requirement of melting a certain quantity of snow or ice at the ice-pavement interface, and on how much of a chemical or of a mixture of chemicals is required to do that.

Feasibility of Visualization and Simulation Applications to Improve Work Zone Safety and Mobility

Visualization is a relatively recent tool available to engineers for enhancing transportation project design through improved communication, decision making, and stakeholder feedback. Current visualization techniques include image composites, video composites, 2D drawings, drive-through or fly-through animations, 3D rendering models, virtual reality, and 4D CAD. These methods are used mainly to communicate within the design and construction team and between the team and external stakeholders. Use of visualization improves understanding of design intent and project concepts and facilitates effective decision making. However, visualization tools are typically used for presentation only in large-scale urban projects. Visualization is not widely accepted due to a lack of demonstrated engineering benefits for typical agency projects, such as small- and medium-sized projects, rural projects, and projects where external stakeholder communication is not a major issue. Furthermore, there is a perceived high cost of investment of both financial and human capital in adopting visualization tools. The most advanced visualization technique of virtual reality has only been used in academic research settings, and 4D CAD has been used on a very limited basis for highly complicated specialty projects. However, there are a number of less intensive visualization methods available which may provide some benefit to many agency projects. In this paper, we present the results of a feasibility study examining the use of visualization and simulation applications for improving highway planning, design, construction, and safety and mobility.

Feasibility of Visualization and Simulation Applications, Tech Transfer Summary, 2008

Visualization is a relatively recent tool available to engineers for enhancing transportation project design through improved communication, decision making, and stakeholder feedback. Current visualization techniques include image composites, video composites, 2D drawings, drive-through or fly-through animations, 3D rendering models, virtual reality, and 4D CAD. These methods are used mainly to communicate within the design and construction team and between the team and external stakeholders. Use of visualization improves understanding of design intent and project concepts and facilitates effective decision making. However, visualization tools are typically used for presentation only in large-scale urban projects. Visualization is not widely accepted due to a lack of demonstrated engineering benefits for typical agency projects, such as small- and medium-sized projects, rural projects, and projects where external stakeholder communication is not a major issue. Furthermore, there is a perceived high cost of investment of both financial and human capital in adopting visualization tools. The most advanced visualization technique of virtual reality has only been used in academic research settings, and 4D CAD has been used on a very limited basis for highly complicated specialty projects. However, there are a number of less intensive visualization methods available which may provide some benefit to many agency projects. In this paper, we present the results of a feasibility study examining the use of visualization and simulation applications for improving highway planning, design, construction, and safety and mobility.

Work Zone Simulation Model, 1999

To support the analysis of driver behavior at rural freeway work zone lane closure merge points, Center for Transportation Research and Education staff collected traffic data at merge areas using video image processing technology. The collection of data and the calculation of the capacity of lane closures are reported in a companion report, "Traffic Management Strategies for Merge Areas in Rural Interstate Work Zones". These data are used in the work reported in this document and are used to calibrate a microscopic simulation model of a typical, Iowa rural freeway lane closure. The model developed is a high fidelity computer simulation with an animation interface. It simulates traffic operations at a work zone lane closure. This model enables traffic engineers to visually demonstrate the forecasted delay that is likely to result when freeway reconstruction makes it necessary to close freeway lanes. Further, the model is also sensitive to variations in driver behavior and is used to test the impact of slow moving vehicles and other driver behaviors. This report consists of two parts. The first part describes the development of the work zone simulation model. The simulation analysis is calibrated and verified through data collected at a work zone in Interstate Highway 80 in Scott County, Iowa. The second part is a user's manual for the simulation model, which is provided to assist users with its set up and operation. No prior computer programming skills are required to use the simulation model.