Tag Archives: Federal Highway Administration

Publication Explains Concrete Test Method

The FHWA Mobile Concrete Technology Center (MCTC) is offering a one-page tech transfer document that provides some observations on a simple, inexpensive field testing concrete & cementitious material hydration. Hydration, of course, creates exothermic chemical reactions, which can be monitored by measuring the total heat generated over time.

“Monitoring Concrete Consistency using Semi-Adiabatic Calorimetry” descibes a test method that can monitor batch-to-batch consistency of concrete mixtures.  The test works by casting a standard concrete cylinder, then placing it in the calorimenter, recording the time-temperature curve (or heat signature), then comparing the curves of other samples from the same mixture.    

Calorimeters are described as effective tools during mix design to determine potential material incompatibility or optimal dosages/sequence of addition of admixtures. They can be used to determine setting times and saw cut times in lieu of physical testing.  Semi-adiabatic calorimeters can also be used as a quality control tool to monitor variations in the sources, quantities, and chemistry of portland cement, supplementary cementitious materials, and chemical admixtures during concrete production.  Click here to download a copy of the document.

ACPA Participates in FHWA Long-Term R&D Discussions

ACPA participated in an Expert Task Group for the FHWA Long-Term Infrastructure R&D program.  Leif Wathne participated in the long-term pavement performance (LTPP) group. A second group focuses on long-term bridge performance (LTBP). 

Leif Wathne participated in the meeting, which covered a range of topics related to long-term pavement research. Among the key questions the pavement performance group

  • How has LTPP data fundamentally improved understanding of pavement performance?
  • What are the critical, high-priority knowledge gaps?
  • What are the top 3 analysis projects to submit to NCHRP?
  • What is the ETG’s top priority to be funded by LTPP?

The meeting was held last week at the National Academies of Sciences in Washington, DC. 

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Follow this link to see ACPA’s government affairs repository. 

FHWA Offers Pavement Restoration Checklists

In the resource spotlight this week is the National Concrete Pavement Technology Center’s (CP Tech Center’s) series of updated and new pavement preservation  checklist.

Originally developed by the Federal Highway Administration (FHWA) in 2002, the preservation checklists provide excellent information on innovative pavement preservation techniques. Designed to guide state and local highway preservation/maintenance and inspection staff, the checklists provide useful information to contractors and others with an interest in concrete pavement preservation, repair, and restoration. 

Checklist topics include the following: 

• Joint and Crack Sealing • Full-Depth Repair
• Diamond Grinding • Cross-Stitching
• Dowel-Bar Retrofit • Longitudinal Diamond Grooving
• Partial-Depth Repair  

 

The complete list of 2019 and 2002 checklists may be found on FHWA’s pavement preservation resource website. The CP Tech Center also includes a link to the resources on its curated online library of pavement preservation resources. 

 

Open House Spotlights PEM and Related Testing

An open house event yesterday focused on performance engineered mixtures (PEM), as well as PEM testing methods.  Cosponsored by the Federal Highway Administration, Illinois DOT and Illinois Chapter-ACPA, the event began with presentations describing the PEM approach.  Peter Taylor of the CP Tech Center provided an overview of the PEM approach,  James Krstulovich of the Illinois DOT,  provided an agency perspective on PEM, and Mike Ayers, Illinois Chapter, provided an industry perspective.

The event, which began in Moline, IL, was followed by PEM test demonstrations at Hahn Ready Mix, Sand & Gravel in nearby Davenport, IA.  About 40 professionals representing the FHWA, Illinois DOT, industry and the CP Tech Center attended the open house event. 

PEM was developed in part, due to the traditional testing and acceptance methods, which are based on factors such as strength, slump and air.  Although these are measures of quality, they have little correlation to future performance, says the CP Tech Center, which notes the goal of the PEM transportation pooled fund is “to bring new testing technologies to state agencies and assist in new test methods that will help deliver durable, long-lasting concrete.”

“We need to make a spec that works better than what we have at the moment,”  Taylor said as in his opening remarks.  “As we move away from prescriptive specs, method specs– and move toward giving the contractor and the producer ownership of their mix designs, we have to keep moving away from the prescription, giving the freedom and innovation over to the people making (the concrete),” Krstulovich said.  Ayers said, “What we don’t consider in pavement design is durability issues, and that’s what’s coming back to haunt us.  Performance engineered mixtures is going to go a long way in alleviating that problem.”

Following the insightful presentations, the DOT also provided a brief overview of the I-74 reconstruction project, a joint project among the Illinois and Iowa DOTs to improve the I-74 corridor from Moline to Davenport.  The project includes the replacement of the I-74 bridges over the Mississippi River as well as interchange ramp reconfigurations and local roadway improvements, according to the I-74 River Bridge website.

The open house continued in the afternoon with demonstrations and interactive discussions about our testing methods that support PEM.  They are: the Super Air Meter, which measures air-void characteristics of concrete; surface resistivity testing, a rapid measurement technique to determine the permeability of concrete; the box test, a measure of workability; and the V-Kelly test, also a measurement of workability.

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Photo:  (L-R) Mike Ayers and Peter Taylor discuss surface resistivity testing during the PEM workshop.  (Photo by Bill Davenport for ACPA)

Meeting Focuses on Collaborative Airport Pavement Research

Officials from the FAA’s William J. Hughes Technical Center, ACPA, and CP Tech Center met in Atlantic City this week to discuss ways the three organizations may work collaboratively on applied research for airfield concrete pavements.

“We appreciate the warm reception, tour, and generous amount of time we spent with Dr. Michel Hovan, FAA Airport Technology Manager and Jeff Gagnon, FAA Airport Pavement R&D Section Manager,” said ACPA President & CEO Jerry Voigt. “It gave us greater insights into some of the research the FAA is doing in the area of airside pavements.  The meeting also afforded ACPA and the CP Tech Center the opportunity to discuss research efforts with the FHWA and ACPA’s ongoing advocacy efforts, which have included specific airport pavement and highway pavement research programs.”

The meeting included an overview and discussion of current FAA research projects; CP Tech Center’s highway research & tech transfer efforts; and ACPA’s ongoing Federal advocacy efforts. 

“We discussed funding and how ACPA has worked with Federal agencies such as the FAA, FHWA, and Military Tri-Services, as well as elected officials in Washington, D.C.,” says Gary Mitchell, VP of Airports and Pavement Technology. “Our efforts include both highway and airport programmatic funding, but provisions that directly support funding for applied research.” This includes the long-standing AID-PT program, as well as a similar research provision included in the FAA Reauthorization Act of 2018 Sec. 744 (Research and deployment of certain airfield pavement technologies). 

Mitchell serves on the FAA’s Research, Engineering, & Development Advisory Committee (REDAC), Subcommittee on Airports, which supports the development of the FAA‘s research and development portfolio through strategic planning, budget formulation, program execution, and program evaluation. ACPA’s Chairman Mack, P.E., (CEMEX) has recently been nominated to serve on the Subcommittee as well and is waiting conformation from the current Administration.

“In the near term,” Mitchell explains, “We will continue the dialogue as we also continue to push for funding to support research for airfield concrete pavements.  Longer term, our goal is to partner with the CP Tech Center and work collaboratively on  applied research projects with the FAA.”

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Photo:  Top photo (L to R) shows Dr. Michel Hovan, Gary Mitchell, Jerry Voigt, Dr. Peter Taylor, Gordon Smith, Jim Mack, Leif Wathne, and Jeff Gagnon at the Hughes Technical Center. The photo below shows one of two accelerated load facilities at the FAA’s research center.  Mitchell explained the two ALF machines are capable of simulating wheel loads of virtually any fixed wing aircraft in the US fleet. The machine shown also allows testing under various climatic conditions.

*  The Accelerated Implementation and Deployment of Pavement Technologies (AID-PT) is a provision first included in the Moving Ahead for Progress in the 21st Century Act (MAP 21).  This ACPA-led initiative created both a mechanism and funding for the delivery of pavement technology.  In 2015, Congress included the program in the Fixing America’s Surface Transportation (FAST) Act, which provides funding through 2020.

Follow this link to see ACPA’s government affairs repository.

 

 

 

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Tue 22

ACPA 2019 Airport Pavements Workshop

October 22 - October 24
Fri 25

Past Chairmen’s Call (2019)

October 25 @ 10:00 am - 11:00 am
Tue 29

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