The National Concrete Consortium (NCC) E-News is the newsletter of the Long-Term Plan for Concrete Pavement Research and Technology (CP Road Map), a national research plan developed and jointly implemented by the concrete pavement stakeholder community.
Moving Advancements into Practice (MAP) Brief describes promising research and technologies that can be used now to enhance concrete paving practices. The September 2017 MAP Brief, “Concrete Pavement Recycling – Project Selection and Scoping” provides guidance on identifying projects that may be good candidates for concrete recycling as well as considerations for uses of recycled concrete aggregate. For a PDF of the SEPTEMBER 2017 MAP Brief, please click on image below or go to: http://www.cproadmap.org/publications/MAPbriefSept2017.pdf.
NCC State Survey Summaries: Member states of the National Concrete Consortium (NCC) have the ability to poll other member states regarding specifications, materials, construction, research, or other issues related to concrete paving. This section highlights some of the questions posed and answers received through the NCC’s ListServ feature: http://www.cptechcenter.org/ncc/TTCC-NCCListServArchive.cfm.
Tie Bar Pullout Testing: The Michigan Department of Transportation polled the NCC group regarding pullout testing for lane ties. Twenty-four agencies responded. Only four agencies responded that they require pullout testing for cast-in-place lane ties. A few more (7) agencies noted that they require pullout testing for tie bars that are drilled in and anchored with adhesive. For those agencies that do require testing of tie bars, the performance requirements varied widely.
NEWS FROM THE ROAD highlights research around the country that is helping the concrete pavement community meet the research objectives outlined in the CP Road Map:
Use of Recycled Asphalt Pavement in Concrete
Pavement reconstruction and maintenance activities have resulted in large quantities of recycled asphalt pavement (RAP) stockpiles in many areas around the United States. Although a significant portion of this material is recycled into new HMA pavements, additional material remains available. The replacement of coarse aggregate in PCC with RAP has been proposed as a method that could provide economic and environmental benefits by providing a means to dispose of excess RAP and reducing the demand for virgin aggregates. This project … To READ the rest of this article, for the Texas DOT Document, CP Road Map Track 1: “Materials and Mixes for Concrete Pavements” and Track 12: “Concrete Pavement Sustainability”, please go to: http://www.cproadmap.org/publications/e-news_Sept2017.cfm.
Roller Compacted Concrete over Soil Cement Under Accelerated Loading
Thin roller compacted concrete (RCC) pavements (i.e., pavements < 8″) have drawn significant interest recently due to their potential in situations with low volume heavy-truck traffic. The objectives of this study were to determine the structural performance and load carrying capacity of thin RCC surfaces under accelerated pavement testing (APT) and for determining the applicability of adding a cement-treated or stabilized base to the pavement system. To READ the rest of this article, the Louisiana DOT and Development (and others’) document, and the research objectives identified in CP Road Map “Track 8: Materials and Mixes for Concrete Pavement”, please go to: http://www.cproadmap.org/publications/e-news_Sept2017.cfm.
Cracking and Debonding of a Thin Fiber Reinforced Concrete Overlay
The use of fiber reinforcing in conjunction with concrete overlays has gained favor as it aids in minimizing crack widths, reduces surface spalling, and increases wear resistance. Previous reports of field constructed fiber reinforced concrete (FRC) overlays indicate that the use of fiber reinforcement reduces the rate of debonding.
The objectives of this project were to determine the impact of incorporating fibers on bond by means of wedge splitting and shear bonding tests. Three different types of fibers (slender and long polymeric, long polymeric, and short steel) at two different dosage rates were evaluated. To READ the rest of this article, for the USDOT (and others’) Document, research objectives identified in CP Road Map “Track 8: Materials and Mixes for Concrete Pavements”, please go to: http://www.cproadmap.org/publications/e-news_Sept2017.cfm.
Load Transfer Restoration with Diamond Grinding on Rigid Pavements
This research paper evaluated the short- and long-term effects of load transfer restoration (also called dowel bar retrofit) with diamond grinding (LTR/DG). Dowel bar retrofit and diamond grinding are the two most commonly used concrete-surface pavement restoration treatments. These treatments are estimated to extend pavement life by 10–15 years; however, little research has been completed to predict the effect of LTR/DG on service life. To READ the rest of this article, for the TRB committee AFD50–Standing Committee on Design and Rehabilitation of Concrete Pavements (and others’) document, and for research objectives identified in CP Road Map “Track 7: Concrete Pavement Maintenance and Preservation”, please go to: http://www.cproadmap.org/publications/e-news_Sept2017.cfm.
To read the September E-News, click on the link following each article highlighted above, on the image to the right above, or go to: http://www.cproadmap.org/publications/e-news_Sept2017.cfm.
To learn more about the CP Road Map or learn how you can get involved, please contact:
Steve Klocke, Snyder & Associates Program Manager:
E-mail: sklocke@snyder-associates.com
Dale Harrington, Snyder & Associates Program Manager:
E-mail: dharrington@snyder-associates.com
Sabrina-Shields Cook, Editor:
E-mail: shieldsc@iastate.edu
Marcia Brink, Managing Editor:
E-mail: mbrink@iastate.edu
Phone: 515.964.2020