Evaluation of an Epoxy Pavement Marking System, HR-180, 1978

The purpose of this research project is to determine if (1) epoxy lane markings will last an entire winter season without replacement, (2) epoxy lane marking is an economical alternative to standard paint on high-traffic multi-lane roadways where lane changing is frequent, and (3) there are worthwhile benefits derived from thorough cleaning of the pavement surface before painting. The success of epoxy lane marking depends on the success of the equipment with which it is mixed and applied. The epoxy lane marking material, if properly mixed and placed on a clean surface, has the durability required to withstand a high traffic volume and frequent lane changes for at least one year.

Engineering Study for the Evaluation of Public Road Administration and Maintenance Alternatives, Executive Summary for HR-265, 1985

Iowa's public road system of 112,000 miles is one of the largest and the best in the nation. It represents a considerable financial investment of taxpayer revenues over the years. And, it requires a sustained investment to preserve an economical level of transport service into the future. In 1982, a Governor's Blue Ribbon Transportation Task Force evaluated the effectiveness of Iowa's entire transportation system. Four important Task Force recommendations dealt with public road administrative issues in Iowa. These issues were related to: 1. design criteria and levels of maintenance 2. consistency in the use of standards among jurisdictions 3. consolidation of maintenance operations at one jurisdictional level and 4. jurisdictional authority for roads. The issues formed the background for Research Project HR-265.

ProScan Automated Profilogram Reduction System, MLR-94-7, 1994

Kansas State University, with funding from the Kansas Department of Transportation (KDOT), has developed a computerized reduction system for profilograms produced by mechanical profilographs. The commercial version of the system (ProScan (trademark)) is marketed by Devore Systems, Inc. The system consists of an IBM Compatible PC 486SX33 computer or better, Epson LQ-570 printer, a Logitech Scanman 32 hand scanner system, a paper transport unit, and the ProScan software. The Scanner is not adaptable to IBM computers with the micro channel architecture. The Iowa DOT Transportation Centers could realize the following advantages by using ProScan: (1) Save about 5 to 8 staff hours of reduction and reporting time per Transportation Center per week for a Materials Technician 3 or 4 (the time savings would come during the busiest part of the season); (2) Reduce errors in reduction, transfer, and typing of profile values; (3) Increase the accuracy of the monitor results; and (4) Allow rapid evaluation of contractor traces when tolerance limits between monitor and certified results are exceeded.

A Study of Portland Cement Maintenance Mix and Set Accelerators, R-249, 1970

The large volume of traffic on the interstate system makes it difficult to make pavement repairs. The maintenance crew needs 4-5 hours to break out the concrete to be replaced and prepare the hole for placing new concrete. Because of this it is usually noon before the patch can be placed. Since it is desirable to remove the barricades before dark there are only 7-8 hours for the concrete to reach the required strength. There exists a need for a concrete that can reach the necessary strength (modulus of rupture = 500 psi) in 7-8 hours. The purpose of this study is to determine if type III cement and/or an accelerator can be used in an M-4 mix to yield a fast setting patch with very little shrinkage. It is recognized that calcium chloride is a corrosive material and may therefore have detrimental effects upon the reinforcing steel. The study of these effects, however, is beyond the scope of this investigation.

Pilot Project for a Hybrid Road-Flooding Forecasting System on Squaw Creek, TR-642

A network of 25 sonic stage sensors were deployed in the Squaw Creek basin upstream from Ames Iowa to determine if the state-of-the-art distributed hydrological model CUENCAS can produce reliable information for all road crossings including those that cross small creeks draining basins as small as 1 sq. mile. A hydraulic model was implemented for the major tributaries of the Squaw Creek where IFC sonic instruments were deployed and it was coupled to CUENCAS to validate the predictions made at small tributaries in the basin. This study demonstrates that the predictions made by the hydrological model at internal locations in the basins are as accurate as the predictions made at the outlet of the basin. Final rating curves based on surveyed cross sections were developed for the 22 IFC-bridge sites that are currently operating, and routine forecast is provided at those locations (see IFIS). Rating curves were developed for 60 additional bridge locations in the basin, however, we do not use those rating curves for routine forecast because the lack of accuracy of LiDAR derived cross sections is not optimal. The results of our work form the basis for two papers that have been submitted for publication to the Journal of Hydrological Engineering. Peer review of our work will gives a strong footing to our ability to expand our results from the pilot Squaw Creek basin to all basins in Iowa.

Policy for Accommodating and Adjustment of Utilities on the Primary Road System, 2012

This chapter covers initial placement, adjustment, and maintenance of utility facilities in, on, above or below the right-of-way of primary highways, including attachments to primary highway structures. It embodies the basic specifications and standards needed to ensure the safety of the highway user and the integrity of the highway. (2012 revision to 2005 policy.)

Policy of the Iowa Department of Transportation Highway Division For Accommodating Utilities on the Primary Road System, 1992

This chapter covers initial placement, adjustment, improvement, relocation, replacement and maintenance of utility facilities in, on, above or below the right-of-way over of primary highways, including attachments to primary highway structures. It embodies the basic specifications and standards needed, to ensure the safety of the highway user and the integrity of the highway. (1992 revision to 1990 policy.)

Policy for Accommodating and Adjustment of Utilities on the Primary Road System, 2005

This chapter covers initial placement, adjustment, and maintenance of utility facilities in, on, above or below the right-of-way of primary highways, including attachments to primary highway structures. It embodies the basic specifications and standards needed, to ensure the safety of the highway user and the integrity of the highway. (2005 revision to 1992 policy.)

Effect of Video Camera-Based Remote Roadway Condition Monitoring on Snow Removal-Related Maintenance Operations. 2014

Remote monitoring through the use of cameras is widely utilized for traffic operation, but has not been utilized widely for roadway maintenance operations. The Utah Department of Transportation (UDOT) has implemented a new remote monitoring system, referred to as a Cloud-enabled Remote Video Streaming (CRVS) camera system for snow removal-related maintenance operations in the winter. The purpose of this study was to evaluate the effectiveness of the use of the CRVS camera system in snow removal-related maintenance operations. This study was conducted in two parts: opinion surveys of maintenance station supervisors and an analysis on snow removal-related maintenance costs. The responses to the opinion surveys mostly displayed positive reviews of the use of the CRVS cameras. On a scale of 1 (least effective) to 5 (most effective), the average overall effectiveness given by the station supervisors was 4.3. An expedition trip for this study was defined as a trip that was made to just check the roadways if snow-removal was necessary. The average of the responses received from surveys was calculated to be a 33 percent reduction in expedition trips. For the second part of this study, an analysis was performed on the snow removal-related maintenance cost data provided by UDOT to see if the installation of a CRVS camera had an effect in reducing expedition trips. This expedition cost comparison was performed for 10 sets of maintenance stations within Utah. It was difficult to make any definitive inferences from the comparison of expedition costs over the years for which precipitation and expedition cost data were available; hence a statistical analysis was performed using the Mixed Model ANOVA. This analysis resulted in an average of 14 percent higher ratio of expedition costs at maintenance stations with a CRVS camera before the installation of the camera compared to the ratio of expedition costs after the installation of the camera. This difference was not proven to be statistically significant at the 95 percent confident level, but indicated that the installation of CRVS cameras was on the average helpful in reducing expedition costs and may be considered practically significant. It is recommended that more detailed and consistent maintenance cost records be prepared for accurate analysis of cost records for this type of study in the future.

Report and Specification for Transportation Program Management System, HR-394, 1997

TPMS is proposed as a distributed, PC-based system for automating two processes required for road improvements in Iowa: a) the annual preparation, submission, and approval of road improvement programs. b) the ongoing process of developing plans and obtaining approval for projects to be let for bids.

Iowa DOT Evaluation of the PASCO Road Survey System, HR-539, 1987

The report compares and contrasts the automated PASCO method of pavement evaluation to the manual procedures used by the Iowa Department of Transportation (DOT) to evaluate pavement condition. Iowa DOT's use of IJK and BPR roadmeters and manual crack and patch surveys are compared to PASCO's use of 35-mm photography, artificial lighting and hairline projection, tracking wheels and lasers to measure ride, cracking and patching, rut depths, and roughness. The Iowa DOT method provides a Present Serviceability Index (PSI) value and PASCO provides a Maintenance Control Index (MCI). Seven sections of Interstate Highway, county roads and city streets, and one shoulder section were tested with different speeds of data collection, surface types and textures, and stop and start conditions. High correlation of results between the two methods in the measurement of roughness (0.93 for the tracking wheel and 0.84 for the laser method) were recorded. Rut depth correlations of 0.61 and cracking of 0.32 are attributed to PASCO's more comprehensive measurement techniques. A cost analysis of the data provided by both systems indicates that PASCO is capable of providing a comparable result with improved accuracy at a cost of $125-$150 or less per two-lane mile depending on survey mileage. Improved data collection speed, accuracy, and reliability, and a visible record of pavement condition for comparable costs are available. The PASCO system's ability to provide the data required in the Highway Pavement Distress Identification Manual, the Pavement Condition Rating Guide, and the Strategic Highway Research Program Long Term Pavement Performance (LTPP) Studies, is also outlined in the report.

Chloride Penetration Into LSDC (Iowa System) Resurfacing Mixes, MLR-77-05 and R-267, 1977

The purpose of this investigation was to determine the comparative effectiveness of standard D-57 concrete and Iowa system Low Slump Dense Concrete in preventing threshold levels of chloride from penetrating the concrete slabs to the reinforcing steel.

Performance of Poly-Carb, Inc. Flexogrid Bridge Overlay System, MLR-86-04, 2001

Intrusion of deicing materials and surface water into concrete bridge decks is a main contributor in deck reinforcing steel corrosion and concrete delamination. Salt, spread on bridge decks to melt ice, dissolves in water and permeates voids in the concrete deck. When the chloride content of the concrete in contact with reinforcing steel reaches a high enough concentration, the steel oxidizes. In Iowa, the method used to reduce bridge deck chloride penetration is the application of a low slump dense concrete overlay after the completion of all Class A and Class B floor repairs. A possible alternative to the use of dense concrete overlays, developed by Poly-Carb, Inc., is the MARK-163 FLEXOGRID Overlay System. FLEXOGRID is a two component system of epoxy and urethane which is applied on a bridge deck to a minimum thickness of ¼ inch. An aggregate mixture of silica quartz and aluminum oxide is broadcast onto the epoxy at a prescribed rate to provide deck protection and superior friction properties. The material is mixed on site and applied to the deck in a series of lifts (usually two) until the desired overlay thickness has been attained.

Evaluation of the Consolid System of Soil Stabilization, MLR-86-10, 1987

The Consolid System by American Consolid Inc. is a three product system that, according to product literature, "enables any soil, found anywhere, to be upgraded to achieve better characteristics necessary in improving road life and quality". Consolid was evaluated along with mixes of cement-fly ash and hydrated lime on two soils. The soils were an A-2-4(0) with zero plasticity index and an A-7-8(18) with a 31 plasticity index. American Consolid Inc. recommended an application rate of 0.10% Consolid 444 and 1.00% Conservex by dry soil weight. The application rate chosen for cement-fly ash was 5% cement and 15% fly ash and for hydrated lime it was 6.5%. Testing involved triaxial testing of specimens after water soaking, unconfined compressive strength of specimens before and after water soaking, and freeze and thaw testing of specimens after water soaking. All specimens were compacted to standard proctor at optimum moisture. The cement-fly ash treated mixes had the highest strength and durability followed by the hydrated lime treated mixes.

Field Testing of Abrasive Delivery Systems in Winter Maintenance, TR-458, 2009

The key goals in winter maintenance operations are preserving the safety and mobility of the traveling public. To do this, it is in general necessary to try to increase the friction of the road surface above the typical friction levels found on a snow or ice covered roadway. Because of prior work on the performance of abrasives (discussed in greater detail in chapter 2) a key concern when using abrasives has become how to ensure the greatest increase in pavement friction when using abrasives for the longest period of time. There are a number of ways in which the usage of abrasives can be optimized, and these methods are discussed and compared in this report. In addition, results of an Iowa DOT test of zero-velocity spreaders are presented. Additionally in this study the results of field studies conducted in Johnson County Iowa on the road surface friction of pavements treated with abrasive applications using different modes of delivery are presented. The experiments were not able to determine any significant difference in material placement performance between a standard delivery system and a chute based delivery system. The report makes a number of recommendations based upon the reviews and the experiments.