I-94 Dartmouth Bridge Noise Study

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Creator
Date Created
1998-11
Report Number
P99-8
Description
Residents who lived near the I-94 Dartmouth Bridge noted an increase in traffic noise that resulted after completion of bridge construction in fall 1996. To help reduce the noise on I-94 between Riverside and Franklin Avenues, the Minnesota Department of Transportation (Mn/DOT) decided to investigate the effectiveness of diamond grading. In July 1998, the bridge pavement and adjacent concrete pavements were diamond ground. Researchers performed noise measurements in the adjacent residential areas before and after the grinding, which was done to entirely eliminate the tining from the bridge deck and pavement. The grinding specifications limited the grinding to approximately 3/16-inch in depth and taper to no inches at the inside and outside shoulders. Researchers measured traffic and noise levels at six locations in the study area during June and September 1998. Overall, diamond grinding of tined concrete pavement succeeded in decreasing noise levels.

Responses and Performance of Stabilized Full Depth Reclaimed Pavements at MnROAD

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Date Created
2012
Description
This paper details the efforts regarding the construction and analysis of three stabilized full-depth reclamation (SFDR) sections (cells 2, 3, and 4) constructed at the Minnesota Road Research Facility (MnROAD) on I-94 in 2008. Three test sections with varying pulverized asphalt concrete/granular base ratios were constructed in order to study the performance of full-depth reclaimed (FDR) pavements stabilized with engineered emulsion. Emulsion content and base structure varied between test sections. Each test section was designed for 3.5 million ESALs over a period of five years. The sections have been subjected to approximately 2.2 million ESALs as of 30 June 2012. Strain gages were embedded at the bottom of the hot-mix asphalt (HMA) and SFDR layers in each test section to measure responses. The strain gages indicate that both the bottom of the HMA and SFDR layers are subject to horizontal tensile strain from falling weight deflectometer (FWD) and heavy vehicle loading. Pavement performance in terms of rutting, cracking, and international roughness index (IRI) has been measured periodically. The results indicate that all three cells are performing well. The only crack in the three cells exists in cell 3, IRI values are well within the acceptable range, and rutting, while progressing, is still acceptable. Finally, the paper concludes with modeled responses and performance predictions from DARWinME and BISAR. Model predictions indicate that a SFDR layer will provide greater structural benefits and increased performance than similar structures with unstabilized FDR or granular base layers. Content Note: This is the author’s version of a work that was accepted for publication in the Transportation Research Record: Journal of the Transportation Research Board, Issue Number: 2368, Publisher: Transportation Research Board ISSN: 0361-1981. The final version can be found at https://doi.org/10.3141/2368-11.

PG XX-34 Effect on Transverse Cracking in Minnesota

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Date Created
2011
Description
The Minnesota Department of Transportation adopted the use of performance graded (PG) asphalt binder in 1997 and in 1999 required PG XX-34 binders for all new (not overlays) bituminous construction with the objective of reducing the amount of transverse cracking. Pavement management data was used to track the development of transverse cracking on PG XX-34 projects. The transverse cracking rate of the PG XX-34 projects was then compared to the historic cracking rates for like projects from the pre PG era. The comparison found that after seven years service, transverse cracks on the PG projects are developing at approximately one tenth the rate experienced before performance grading was implemented. Content Note: This is the author’s version of a work that was accepted for publication in the Transportation Research Record: Journal of the Transportation Research Board, Issue Number: 2207, Publisher: Transportation Research Board ISSN: 0361-1981. The final version can be found at https://doi.org/10.3141/2207-08.

Effect of Crack Sealant Material and Reservoir Geometry on Surface Roughness of Bituminous Overlays

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Date Created
2008
Description
Many state, county, and municipal highway agencies have experienced the formation of bumps when placing single-lift overlays or the first lift of a multiple lift overlay. These bumps are produced at the location of a previously-existing crack, and even then almost exclusively when the crack has been sealed prior to the overlay. When such bumps are not covered with a subsequent lift, what remains is often a rough ride on a newly-overlaid roadway. This paper describes the effects of crack sealant material type and the geometry (shape) of the routed cracks in the existing surface on the formation of bumps in bituminous overlays. A matrix of four sealant type treatments and six geometries was designed, and implemented in a test section in Jackson County, Minnesota. The overlay on the test section was constructed in September 2007. The results of this investigation indicate that cooler pavement surface temperatures, no overband, hot-poured crumb rubber and hot-poured elastic sealants provided the best resistance to the formation of bumps in overlays. Content Note: This is the author’s version of a work that was accepted for publication in the Transportation Research Record: Journal of the Transportation Research Board, Issue Number: 2108, Publisher: Transportation Research Board ISSN: 0361-1981. The final version can be found at https://doi.org/10.3141/2108-08.

Resilient Modulus of MnROAD Subgrade Soil

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Date Created
2002
Description
Laboratory remolded subgrade soil samples have been widely used to study subgrade resilient modulus. But physical conditions, such as moisture content and density, of such specimens may not represent in-situ conditions very well. Therefore, AASHTO and the Long-Term Pavement Performance program (LTPP) have recommended that undisturbed thin-walled tube samples should be used to study subgrade resilient behavior. The Minnesota Department of Transportation (Mn/DOT) is developing mechanistic-empirical pavement design approaches through the Minnesota Road Research project and has realized the importance of resilient modulus in the design approaches. Currently, the Mn/DOT is making an effort to study resilient modulus of unbound pavement materials through laboratory experiments. Under a research project at the Mn/DOT, several thin-walled tube samples of subgrade soil were obtained from six different pavement sections at the Minnesota Road Research project. Repeated loading triaxial tests were conducted on the soil specimens to determine resilient modulus at the Mn/DOT laboratory. Also, some soil properties, such as resistance R-value and plasticity index were obtained. R-value is an indicative value of performance when soil is placed in the subgrade of a road subjected to traffic. Two constitutive models (Uzan-Witczak universal model and the deviator stress model) were applied to describe the resilient modulus. The objective of the research was to compare these two well-known constitutive models in describing subgrade soil resilient behavior and to study effects of material properties on the resilient modulus. From the specimens tested, the experimental results showed that the universal model described the subgrade resilient modulus slightly better than the deviator stress model and the coefficients in these two constitutive models were found to have correlation to material properties. Also, no well-defined relationships between R-value and the coefficients in the constitutive models were observed from the results of the tested specimens. Content Note: This is the author’s version of a work that was accepted for publication in the Transportation Research Record: Journal of the Transportation Research Board, Issue Number: 1786, Publisher: Transportation Research Board ISSN: 0361-1981. The final version can be found at https://doi.org/10.3141/1786-03.

Determining the Low-Temperature Fracture Toughness of Asphalt Mixtures

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Date Created
2001
Description
There has been a sustained effort in applying fracture mechanics concepts to crack formation and propagation in bituminous pavement materials. Adequate fracture resistance is an essential requirement for asphalt pavements built in the northern part of the US and Canada for which the prevailing failure mode is cracking due to low-temperature shrinkage stresses. The current Superpave specifications address this issue mainly through the use of strength tests on unnotched (smooth boundary) specimens. However, recent studies have shown the limitations of this approach and have suggested that fracture mechanics concepts, based on tests performed on notched samples, should be employed instead. Research in progress at University of Minnesota investigates the use of fracture mechanics principles to determine the low-temperature fracture properties of asphalt mixtures. This paper presents a testing protocol that allows obtaining multiple measurements of fracture toughness as a function of crack propagation based on the compliance method to measure crack length. An increase in fracture toughness with crack length is observed, which is consistent with the behavior displayed by other brittle materials. The plateau of the curves may be representative of the asphalt concrete resistance to fracture because the initial values can be significantly influenced by the presence of the inelastic zone at the crack tip. Content Note: This is the author’s version of a work that was accepted for publication in the Transportation Research Record: Journal of the Transportation Research Board, Issue Number: 1789, Publisher: Transportation Research Board ISSN: 0361-1981. The final version can be found at https://doi.org/10.3141/1789-21.

Field Installation of an Earth Pressure Cell

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Date Created
2001
Description
An earth pressure cell (EPC) is a device designed to provide an estimate of normal stress in soil. The practice of designing and manufacturing stress measurement devices revolves around the study of the interaction between the measuring device – the earth pressure cell – and the host material. However, distribution of normal stress is not necessarily uniform across a given surface. Consequently, output from an EPC may be different under soil loading conditions than under fluid pressure. In addition, depending upon the design, as the cell deflects, an arching-type phenomenon may develop. The objectives of this study were to devise a scheme for calibration of earth pressure cells and to recommend a procedure for field installation. A new testing device was designed to permit the application of uniaxial soil pressure to the earth pressure cell using various types of soil and load configurations. Sensitivities computed from soil calibrations varied from those determined from fluid calibrations by as much as 30%. A field installation procedure was developed from model tests. In the laboratory, a thin-walled steel cylinder with a geotextile bottom was filled with uniform silica sand in a medium dense state and the earth pressure cell was placed within the sand. The entire apparatus (earth pressure cell, cylinder, and sand) was carried into the field and installed in the desired locations. Once in place, the steel cylinder was pulled up out of the ground, leaving the cell, sand, and geotextile behind. Preliminary field data indicate that the soil calibration and placement procedure provide reasonably accurate measurements of the change in vertical stress. Content Note: This is the author’s version of a work that was accepted for publication in the Transportation Research Record: Journal of the Transportation Research Board, Issue Number: 1772, Publisher: Transportation Research Board ISSN: 0361-1981. The final version can be found at https://doi.org/10.3141/1772-02.

Interpreting Traces From a Lossy TDR System and Optimizing System Performance

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Date Created
1998-02
Report Number
1998-03U
Description
The Minnesota Road Research Project (Mn/ROAD) has completed time domain reflectometry measurements of soil moisture since 1993. But questions about interpretation about the data remain, because of soil characteristics at the site, the unusual design of waveguides, and long transmission lines that are known to degrade TOR system performance. This study's objectives included developing a procedure to recover moisture content data measured in situ with TOR since 1993 at the Mn/ROAD site. Researchers calibrated the relationship between TOR system response and soil water content and characterized the influences of unusual waveguide design, high soil bulk density, high soil clay content, cable length, and soil temperature. Cable lengths greater than 33 m caused errors in the TOR calibration relationship. In addition, soil temperature had a small effect on TDR measurements. Researchers developed correction equations to correct TOR measurements of water content for long cable lengths and soil temperature. Past TDR moisture measurements taken at the Mn/ROAD site must be interpreted using this report's calibration equation and cable length/soil temperature corrections. Additionally, present and future interpretations of soil moisture using the existing TDR system at the Mn/ROAD site must use these equations. This report is unpublished. 15 copies were produced and distributed.

Minnesota Roadway Research Project

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Date Created
1990-05
Report Number
95-01U
Description
The Minnesota Department of Transportation (Mn/DOT) has proposed the development of a Road Research Facility which will be located in Wright County, between Monticello and Albertville. The intent of this project is to provide a facility where intensive research on flexible and rigid pavements can be conducted using "real world" vehicle loading. To this end, a Pavement Research Test Facility Task Force was formed to oversee the implementation of the facility. To assist Mn/DOT in the development of the test facility, the services of the University of Minnesota and the National Engineering Technology Corporation (NET) have been obtained. The Civil and Mineral Engineering Department of the University will provide guidance to Mn/DOT on sensor selection and usage. The Computer Science Department of the University will design the computerized processing system and be responsible for development of the database software. NET's purpose in this project is to develop overall design scenarios, alternatives, costs and recommendations for the preliminary design concepts of the entire system with particular attention to the communications and data collection subsystems. This report will present the various design alternative concepts investigated and the cost estimates for the different subsystems. After analyzing the alternatives, a recommendation is made on the preferred concept together with an implementation and management plan. This report is unpublished. 15 copies were produced and distributed.

2022 MnROAD Construction Activities

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Date Created
2023-11
Report Number
2023-37
Description
The 2022 construction season at the MnROAD facility saw construction of 39 new and unique pavement test sections and the repairs of 6 existing test sections. These sections were planned and designed by the National Road Research Alliance (NRRA) teams to address high-priority research needs. This report details development, design, and construction of each test section supporting the associated research studies developed by the teams. Individual study details are left to future reports generated by the individual research contracts and their respective NRRA teams. As a multi-state, pooled-fund program, the National Road Research Alliance (NRRA) provides strategic implementation of pavement engineering solutions through cooperative research. For Phase II, NRRA focused on improving sustainability and resiliency of our national pavement system and studying and promoting intelligent construction technologies. Based on these goals, some test sections were rehabilitated to extend their life by recycling in-situ material and applying preventive maintenance techniques. Newly constructed tests sections used innovative materials such as plastic, rubber and fibers for asphalt pavements and alternative cementitious, alternative supplementary cementitious, and carbon injection for concrete pavements. Two test sections served perpetual pavement and wicking geotextile research projects. Both were designed and constructed as perpetual pavements one of them with a wicking geotextile on top of the subgrade for improving drainage and stiffness of road foundation and quantifying its long-term benefits. Six test sections were repaired using performance engineered mixes on the replacement panels and finished with diamond grinding to eliminate faulting.