New Standard
Adopted for Recycled Glass in Pavements
The use of recycled materials in pavements has received a boost with
the adoption of a new national specification for recycling glass in
soil aggregate base courses. The specification, entitled "Glass
Cullet Use for Soil Aggregate Base Course," was adopted by the
American Association of State Highway and Transportation Officials
(AASHTO) in December 2000 and will be published in the next edition
of AASHTO's Standard Specifications for Transportation Materials of
Sampling and Testing.
The specification notes that, "When properly processed and mixed
with natural or crushed aggregate, hauled to, and properly spread
and compacted on a prepared grade to appropriate density standards,
glass cullet can be expected to provide adequate stability and load
support for use as road or highway bases."
The new standard was developed as part of a research project conducted
by the Recycled Materials Resource Center (RMRC) at the University
of New Hampshire. This project is designed to investigate the properties
of selected recycled materials and to develop guidance specifications
for highway construction applications in an AASHTO format. Overseeing
the effort is a technical advisory group composed of representatives
from 15 State departments of transportation (DOT).
 |
"The
new AASHTO specification conforms nicely with what we're doing in
Minnesota," says Roger Olson of the Minnesota DOT and a member
of the Technical Advisory Group. Minnesota's specification allows
for up to 10 percent glass cullet use in base courses.
"The specification makes it easier for States," says Frank
Palise of New Jersey DOT and also a member of the Technical Advisory
Group. "Without a specification, it is particularly hard for
county or municipal engineers to try something new. Having an AASHTO
specification makes it easier for States to give the stamp of approval."
According to Taylor Eighmy of the RMRC, "The glass cullet specification
was one that many States were asking for. There was a lot of interest
in it. We're now actively working with States to develop the additional
specifications that they need. "
The five additional specifications currently being developed by the
RMRC research project are:
- Recycled
Concrete Pavement as an Aggregate Substitute Material in Granular
Base
- Recycled
Concrete Pavement as an Aggregate Substitute in Portland Cement
Concrete Pavements
- Recycled
Asphalt Pavement Used in Hot-Mix Asphalt (HMA) at Hot-Mix Plants
- Use of
Asphalt Shingles as Asphalt Cement Replacment in HMA
- Coal
Fly Ash Use in Embankments
The glass
cullet specification can be downloaded from the Web at www.rmrc.unh.edu/Research/Rprojects/project13/Specs/
AASHTO-Rev-03-13-01.pdf.
For more information on the specification, contact Taylor Eighmy at
603-862-1065 (fax: 603-862-3957; email: t.eighmy@rmrc.unh.edu).
| The
13 million tires currently being recalled nationwide by the Ford
Motor Company will be recycled, with Ford having expressed a desire
to see them reused in paving applications. FHWA has been asked
by Ford to provide technical support for this effort. Other partners
that FHWA has asked to join in the effort include AASHTO, the
National Asphalt Pavement Association, Rubber Pavements Association,
and the RMRC. For more information, contact Byron Lord at FHWA,
202-366-1324 (fax: 202-493-2070; email:
byron.lord@fhwa.dot.gov). |
Other
articles in this issue:
In Brief
In and Out in 72 hours
Rhode Island keeps bridge data at its fingertips
National Pavement Preservation forum II: Protection our investment
New standard adopted for recycled glass in pavements
FHWA course offers new look at pavement preservation
Highway technology calendar
