Sharon Van Sluijs

Researchers for Virginia DOT investigated the reasons for premature failure of concrete patches on continuously reinforced concrete pavement. Testing revealed that the use of high early strength mixes with high cement contents and failure to assess the overall pavement condition were the most frequent causes of early patch failure. The study recommended revisions to VDOT’s concrete patching procedures.

Read the research report: Premature Failure of Concrete Patching: Reasons and Resolutions, March 2019.

The Transportation Research Board will conduct a webinar about the applications of continuous pavement deflection technology on Thursday, May 30, from 1:00 to 2:30 p.m. Eastern Time. The ability to collect information on pavement structural capacity at traffic speeds is changing how agencies evaluate their pavement needs. This webinar will explore how agencies can conduct pavement assessments effectively and will compare continuous deflection to traditional methods of assessing pavements.

Read the announcement: TRB Webinar: Continuous Deflection for Comprehensive Pavement Assessment.

(Image courtesy of FHWA.)

The capabilities of a new work zone intrusion alarm system—Advance Warning and Risk Evasion (AWARE)—were recently demonstrated during a Minnesota paving project. The portable radar-based technology detects and tracks potential vehicle intrusion threats and worker locations to warn both workers and errant drivers. MnDOT gained insights about the technology, and the developer is continuing to field-test and refine the system.

Read the project summary: Personal Warning Sensor for Road Construction Workers, February 2019.

Iowa DOT has long used concrete overlays to restore bridge decks and extend their service life. Overlays delaminate over time, but they can be repaired through the injection of epoxy resins into cracks and voids. A recent study sought to learn the actual service life of epoxy repairs as well as the most effective methods and materials for injection. A field investigation and review of industry practices were used to develop specifications.

Read the research report: Investigation and Evaluation of Iowa Department of Transportation Bridge Deck Epoxy Injection Process, February 2019.

New varieties of buffalograss have shown promise as a low-maintenance roadside planting in the Midwest thanks to their excellent drought, cold and salinity tolerance. A recent Kansas DOT study showed that blending buffalograss with perennial ryegrass, which establishes more quickly, can provide short-term roadside stability while allowing time for successful buffalograss establishment.

Read the research report: Preliminary Evaluation of Perennial Ryegrass and Buffalograss Blends for Seeded Roadside Establishment to Comply with Storm Water Control Regulations, December 2018.

To help plan future bridge deck maintenance, researchers for Minnesota DOT analyzed inspection data for nearly 500 bridges that were constructed in the 1970s and 1980s using mixed rebar decks—epoxy-coated rebar in the top layer of the concrete deck and uncoated rebar in the bottom layer. Investigators made inspection and mitigation recommendations based on their analysis of deck deterioration rates.

Read the research report: Deterioration of Mixed Rebar and Fiber-Reinforced Concrete Bridge Decks, February 2019.