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This report highlights an investigation into concrete pavement performance problems caused by transverse joint misalignment on a segment of westbound Interstate 94 near Fergus Falls, Minnesota. In 1986, heavy rain during construction resulted in transverse joint locations based on estimated sawing guide marks. The results of dowel bar alignment, faulting, and load transfer efficiency measurements all demonstrate that misaligned transverse joints in relationship to the dowel bar assemblies contributed to early faulting that a minimum dowel bar embedment length of 64 mm (2.5 in.) is needed to prevent significant faulting and maintain reasonable load transfer efficiency across a joint. However, construction alignment tolerances and long-term concrete stress reduction near the dowels warrant the use of embedment lengths longer than 64 mm (2.5 in.). Since several of the joints investigated can be considered undoweled, accelerated faulting of these joints can be expected.

The Dynamic Cone Penetrometer (DCP) is a test device used for measuring the strength and variability oh unbound layers of soil and granular material. The DCP is not a new test device, but transportation organizations in Canada and the United Stales, including the Strategic Highway Research Program (SHRP), have shown a renewed interest in its unique capability of measuring a profile of in situ foundation characteristics. A desire to more fully characterize subsurface conditions on the Minnesota Road Research Project (Mn/ROAD) led to the initial use of DCP by Mn/DOT. From an operational perspective it is very attractive because the DCP is both portable and simple to use. The objective of this research was to explore ways that IXP's could effectively be used by Minnesota pavement and materials engineers and to perform the testing, analysis, and learning necessary for establishing relationships between DCF' test results and other commonly used foundation parameters. This paper describes the design and operation of the DCP as well as an overview of the theoretical basis for use of the device. In addition, correlation results, data profiles, case histories and related information are presented.

An extensive pavement material sampling and testing program was devised and carried out during construction of the Minnesota Road Research Project (Mn/ROAD). This guide provides comprehensive information regarding the type and location of soil and base material samples collected from the Mn/ROAD project. Information regarding nondestructive soil testing is provided which includes Dynamic Cone Penetrometer (DCP) and Falling Weight Deflectometer (FWD) testing. Material sample information provided is divided into sample types, then into proposed research applications. Sample locations and proposed laboratory tests are shown. Testing locations for the nondestructive tests conducted on the project are provided. Information listed in a "Mn/ROAD ID#" column provides a unique identification to each sample. This sample identification can be used to request samples or obtain test result data contained in the Mn/ROAD database. During construction of the Mn/ROAD project, approximately one third of the samples collected were immediately tested to characterize the subgrade layers of the project. The remaining samples were put into storage for future research needs. Appendices A, B and C contain descriptions of Mn/ROAD database tables related to soil samples and nondestructive tests. Test cell profile diagrams are provided in Appendix D.

This report describes the results for physical characteristics of new jointed plain concrete test cells that replaced an existing aggregate-surfaced test cell and a nearby bituminous-surfaced transition area at the Minnesota Road Research Project (Mn/ROAD), a long-term pavement testing facility. It also summarizes the results of various material tests performed during and immediately following the construction of the test cells.

After seven years of heavy traffic and weathering, three ultra-thin whitetopping test cells on the interstate portion of the Minnesota Road Research project (MnROAD) had reached terminal serviceability. Those three test cells were replaced by four new thin-whitetopping test cells in October 2004. This report describes the physical characteristics of the new whitetopping test cells 60-63. The report also summarizes the results from the material tests and curl and warp measurements taken during, and immediately following, construction of the test cells.

Three instrumented ultra-thin whitetopping (UTW) pavement test sections were constructed in 1997 at the Minnesota Road Research facility (MnROAD). The sections were installed on the interstate highway portion of MnROAD to accelerate the traffic loadings compared to typical applications of UTW. By spring 2004, significant deterioration of the sections had occurred. Prior to replacement of the three test sections in fall 2004, a forensic investigation of the distresses was carried out. The focus of this report was to describe the forensic investigation procedures carried out, and to summarize findings from the investigation. The investigation revealed that the performance of ultra-thin whitetopping test cells at the MnROAD project was related to traffic volume, wheel placement, and layer bonding. Distresses were more frequent and severe in the higher-volume driving lane. Panel sizes that place wheelpaths near the edges of UTW slabs resulted in accelerated distress and poor performance. Bonding of UTW to the underlying asphalt layer was essential for long-term performance. Reflective cracking occurs in bonded concrete overlays for thicknesses less than 5 inches (over 6 inch minimum asphalt layer). Large polyolefin fibers did provide some benefit to crack containment in UTW, but added significant cost to the concrete mix.

In June and July 2013, MnDOT constructed three new concrete pavement test sections or cells at the MnROAD facility. On MnROAD's Interstate 94 mainline, a 7.5 inch thick sustainable concrete pavement was constructed using a 75% recycled concrete aggregate (RCA) mix, to study the performance of recycled aggregates in new concrete. Geocomposite transverse joint drains and preformed neoprene joint seals were also incorporated into this test section. Also on the MnROAD mainline, new bonded concrete overlays of distressed asphalt pavement (BCOA) test sections were built. These BCOA or whitetopping test cells were built with 4 and 5 inch thick fiber reinforced concrete slabs. On MnROAD's Low Volume Road loop, a 3 inch thick ultra-thin unbonded concrete overlay was constructed over two different thicknesses of geotextile fabric interlayer. The concrete overlay also contained structural fibers in the mix. This report documents the design, construction, field testing, sampling and testing, and sensor instrumentation associated with these new test sections. Additionally, a thin 5 inch concrete pavement (cell 32) on the low volume road was repaired and retrofitted with unique load transfer devices; post-repair diamond grinding was performed. The pervious concrete overlay test cell (Cell 39) was ground to ascertain 1) whether slurry from grinding operations significantly impair the permeability. Details about the cells: Mainline sustainable concrete pavement and whitetopping: Cells 613, 140 & 240, and 160-163 (SP 8680-169); Low-volume thin unbonded concrete overlay with geosynthetic interlayer and pervious pavement rehab: Cells 32, 39 (SP 8680-170).

Unbonded concrete overlays are generally used to rehabilitate pavements by restoring lost ride and structural capacity. Historically, their design has been conservative (thick) due to the lack of a rational design method. In the summer of 2008, TH 53 near Duluth, MN, was rehabilitated with a thin (5-inch thick) unbonded concrete overlay. The Minnesota Department of Transportation (Mn/DOT) included the TH 53 overlay as part of a research project on thin unbonded concrete overlays. Falling weight deflectometer (FWD) measurements were taken both before and after construction. A short section of the project was instrumented with electronic sensors designed to collect environmental and load response data. The TH 53 test section is currently undergoing thorough evaluations and rigorous testing in accordance with the research project work plan. This report presents the initial baseline testing results, which include: distress survey and mapping, ride quality measurements, and structural testing. A visual distress survey, conducted in April 2009, revealed that approximately 40 transverse cracks have formed in the overlay over the nearly nine mile project length. FWD measurements indicate that the new pavement is providing good structural support.

In the summer of 2008, after roughly fourteen years of service many of the pavement test cells at the Minnesota Road Research project (MnROAD) required rehabilitation or reconstruction. This massive construction effort was also known as "Phase II" (SP 8680-157). Among the cells that were rehabilitated was Cell 5, which is located on the mainline or interstate 94 section of the research facility. Cell 5 received a thin (4 to 5") unbonded concrete overlay. This cell was heavily instrumented with electronic sensors designed to collect environmental and load response data. In addition the pavement in this cell will be thoroughly evaluated and rigorously tested at various times during the year. The thin design, and consequently shorter life, of this overlay should produce valuable data over the life of the sensors. This report describes the physical characteristics of the new thin unbonded concrete overlay test cell 5 (sub-cells 105-405). Included in the report are the construction plans (including sensor layouts), quantities and bid prices, as well as the special provisions. The report also summarizes the results from the initial material tests, various surface characteristics measurements and other initial test results.

This report examines how full-depth colored concrete performs in Minnesota roadways, and includes recommendations for improved specifications for construction and for repair of existing installations.