Iowa DOT Develops Guidance on Epoxy Repairs of Concrete Overlays April 23, 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.
Buffalograss Blends Offer Best of Both Worlds on Kansas Roadsides April 18, 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.
Minnesota’s Deep Dive into Bridge Inspection Data Brings Insights on Mixed Rebar Decks April 16, 2019 - 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.
Ohio Investigates Catch Basin Inserts for Post-Construction Highway Drainage April 12, 2019 - Researchers for Ohio DOT evaluated the use of catch basin inserts to remove suspended solids from runoff in post-construction areas. Based on performance and cost considerations, the use of catch basin inserts was determined not to be a post-construction stormwater best management practice in Ohio.
Read the research report: Catch Basin Inserts for Ohio Roadways, September 2018.
Colorado Rest Areas Project Evaluates Facilities, Develops Policy Guidance April 9, 2019 - A two-phase study of Colorado DOT’s 27 agency-maintained rest areas seeks to identify how these facilities can complement existing privately owned facilities and ensure that travelers have amenities within a reasonable distance as they travel across the state. The Phase I report documents the study methodology and establishes a baseline for management decisions. The follow-up Phase II report will present specific recommendations.
Read the research report: Statewide Rest Area Study—Phase I Report, Inventory and Assessment, September 2018.
Building Better Microsurfacing and Slurry Seals: TRB Webinar on April 24 April 2, 2019 - The Transportation Research Board will conduct a webinar on Wednesday, April 24, from 1:00 to 2:30 p.m. Eastern Time on microsurfacing and slurry seals. Presenters will discuss the use and construction of these pavement preservation techniques. They will also examine issues practitioners have encountered and discuss possible solutions.
Read the announcement: TRB Webinar: Building Better Micro Surfacing and Slurry Seals.
(Image courtesy of Seattle DOT.)
Invasive Japanese Knotweed May Adversely Affect Roadways Through Erosion March 28, 2019 - A researcher who noted the spread of the highly invasive Japanese knotweed in Vermont after Hurricane Irene continued his investigation into its detrimental effects. The plant spreads vegetatively—without seeds and through disruption—and thrives as it quickly kills groundcover and promotes erosion of banks, such as those along streams and roadways. This TRB conference presentation reveals the plant’s many destructive effects, including those relevant to transportation.
Read the presentation: Japanese Knotweed as a Driver of Streambank Erosion, January 2019.
New Technology Enhances Bridge Deck Inspections in Michigan March 21, 2019 - Researchers for Michigan DOT developed a system to evaluate bridge decks at near-highway speeds. The vehicle-mounted 3D optical bridge evaluation system (3DOBS) uses GPS, a high-tech camera, and an inertial measurement unit to collect bridge deck imagery for inspectors’ use. The system will help bridge inspectors safely quantify deck distresses and optimize the timing of preservation treatments.
Read the research report: Evaluation of Bridge Deck Using Non-Destructive Evaluation (NDE) at Near Highway Speeds for Effective Asset Management, October 2018.
Selected Turfgrass Mixtures Can Withstand Harsh Roadside Environments March 19, 2019 - Researchers for Minnesota DOT tested different grass seed mixtures to determine their ability to survive harsh roadside environments: heat, salt and ice cover. For each stress test, investigators identified top-performing varieties; these will be further field-tested to determine the best mixtures to use along Minnesota roadsides.
Read the research report: Regional Optimization of Roadside Turfgrass Seed Mixtures, December 2018.
Ohio DOT Publishes Culvert Management Manual February 26, 2019 - The Ohio Department of Transportation’s Culvert Management Manual provides guidelines for the inventory and inspection of conduits and structures with a span less than 10 feet measured parallel to the centerline of the highway. The manual provides a regular and systematic approach to aid inspectors as they evaluate these structures in order to perform routine maintenance for the continued safety of the driving public.
Read the manual: Ohio Department of Transportation Culvert Management Manual, September 2018.