In association with the CP Road Map Program
The 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.
Latest CP Tech Center Publications—3 New Concrete Guides for Users—Three new manuals covering different aspects of concrete practices are now available from the National CP Tech Center. These publications are for use by industry professionals interested in the latest information on recycling of aggregates, geotextile use in pavements, and constructing concrete overlays. All three reference works can now be accessed from the CP Tech Center web page.
1. Recycling Concrete Pavement Materials: A Practitioner’s Reference Guide
2. Performance Assessment of Nonwoven Geotextile Materials Used as the Separation Layer for Unbonded Concrete Overlays of Existing Concrete Pavements in the United States
3. Guide for the Development of Concrete Overlay Construction Documents
For the September ISCP ARTICLE on the 3 publications titled “3 New CP Tech Guides Cover Different Aspects of Concrete Practices”, please go to: https://www.concretepavements.org/2018/09/11/3-new-cp-tech-guides-cover-different-aspects-of-concrete-practices/
To read the full article, please click here …
NCC STATE SURVEY—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. The following table highlights the responses of some of the state DOTs on certain concrete pavement test frequencies as received through NCC and as provided by Maria Masten, P.E., MnDOT, Chairperson NC2, September 21, 2018. To read the full article, please click here …
NEWS FROM THE ROAD
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. The research projects and the summaries described herein are the products of the researchers and sponsors. For the continuation of the highlights below, please click on the image to the left, or go to: http://www.cproadmap.org/publications/e-news_Oct2018.cfm#News-1
Precast Concrete Panels for Rapid Full-Depth Repair of CRC Pavement to Maintain Continuity of Longitudinal Reinforcement—This Tech Brief describes a recently implemented method for rapid overnight full-depth repairs of continuously reinforced concrete (CRC) pavements using precast concrete panels. This method, developed by the Illinois Tollway, uses continuous longitudinal reinforcement throughout the repair area to make the method applicable for repairing multiple lanes or large areas, as well as for isolated repairs for long-term performance with minimal impact to traffic. The Illinois Tollway successfully utilized this method for a high traffic-volume expressway in the Chicago metropolitan area. For the full document, please go to: https://www.fhwa.dot.gov/pavement/concrete/pubs/hif18050.pdf
… To read the full article, please click here …
Early-Age Fiber-Reinforced Concrete Properties for Overlays—Fiber-reinforced concrete (FRC) has been used for concrete pavement overlays for a few decades. It is well documented that it improves performance over unreinforced plain concrete in regards to crack initiation and crack propagation. When selecting an appropriate fiber-reinforced concrete for the design of thin overlays, the flexural residual strength is the primary design criteria used. Other material parameters, such as slump, unit weight, air content, compressive strength, shrinkage, and coefficient of thermal expansion, are also commonly measured to determine consistency between mixtures and to be used in design software as the baseline material properties. … To read the full article, please click here …
Prevention of Longitudinal Cracking in Iowa Widened Concrete Pavement—Iowa has adopted 14-ft widened concrete slabs (as opposed to the standard 12-ft concrete slabs) in jointed plain concrete pavement (JPCP) design and construction since the 1990s. The additional 2-ft slab paved beyond the normal traffic path is intended to reduce stresses and deflections at the critical concrete pavement edge location by effectively moving the normal traffic path well away from the edge. However, many widened concrete pavements are now approaching 20 years of service life, and some 14-ft widened concrete pavements are experiencing sudden and significant amounts of longitudinal cracking.
… field investigations were performed at 12 sites in spring and summer 2017 … To download the document, please click on the image to the right, or go to: http://publications.iowa.gov/27886/1/TR-700_%20Final%20Report_longitudinal_cracking_prevention_in_widened_concrete_pvmt_w_cvr.pdf … To read the full article, please click here …
Seasonal Variations and In Situ Assessment of Concrete Pavement Foundation Mechanistic Properties—In cold climates, pavement surface and foundation layers are subjected to seasonal temperature variation and freeze-thaw cycles. The number and duration of freeze-thaw cycles in the foundation layers can significantly influence the pavement performance. Seasonal variation in foundation layers is accounted for in pavement design by empirically adjusting the foundation layer moduli values. This paper presents results from in situ falling weight deflectometer (FWD) and dynamic cone penetrometer (DCP) tests conducted over a two-year period at five sites in Iowa; … To read the full article, please click here …
Bridge Service Life Design—High costs and traffic disruption associated with the deterioration of reinforced concrete bridge decks because of corrosion have sparked renewed interest in service life design. Reinforced concrete bridge decks are exposed to chlorides from deicing salts; when the chlorides reach the steel reinforcement, they initiate corrosion. This study supports the adoption of the methodology described in fib Bulletin 34, Model Code for Service Life Design, for reinforced concrete bridge decks in Virginia. As part of this study, concrete mixture properties and environmental exposure conditions were characterized. … To read the full article, please click here …
Review of National and State-Level Calibrations of AASHTOWare Pavement ME Design for New Jointed Plain Concrete Pavement (report date: 2018)—For the design of new jointed plain concrete pavements (JPCPs), three national calibrations of the AASHTOWare Pavement ME Design have been necessary due to model and database updates. Local calibration is also recommended to better match a state’s experience. To date, 8 states have changed the calibration coefficients to local values, while 11 states have implemented national coefficients. This study presents a review of the national and local calibrations and a comparison in terms of, (1) pavement performance prediction and (2) thickness design. … To read the full article, please click here …
Implementation of a Precast Inverted T-Beam System in Virginia: Part II: Analytic and Field Investigations—The inverted T-beam superstructure is a bridge system that provides an accelerated construction alternative for short-to medium-span bridges. The system consists of adjacent precast inverted T-beams with a cast-in-place concrete topping. This bridge system is expected to not experience the reflective cracking problems manifested in short-to-medium-span bridges constructed with traditional adjacent voided slab or adjacent box beams. This report presents the results of three phases of a comprehensive research project to develop and implement an inverted T-beam system for Virginia. The three phases are … For the full document, please click on the image to the right, or go to: http://www.virginiadot.org/vtrc/main/online_reports/pdf/19-R2.pdf … To read the full article, please click here …
Portland-limestone cement (PLC) is an innovative cement that contains between 5% and 15% nely ground limestone. PLC is a relatively new cement in the United States—the rst application for paving took place in Colorado in 2007. This MAP Brief is intended to review experience with this product over the past 10 years …
To download the October MAP Brief, please click on image to the left, or go to: http://www.cproadmap.org/publications/MAPbriefOctober2018.pdf
If you’d like to find out more about the CP Road Map or learn how you can get involved, contact:
Dale Harrington, HCE Services | E-mail: dharrington@hceservices.com | P: 515-964-2020Sabrina Shields-Cook, Editor | E-mail: shieldsc@iastate.edu