My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
03/13/2017 City Council Agenda
COE
>
City of Eugene
>
Public Meetings
>
CMO
>
2017
>
03-13-2017
>
03/13/2017 City Council Agenda
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
3/10/2017 9:26:29 AM
Creation date
3/10/2017 9:18:58 AM
Metadata
Fields
Template:
City Council
City_Council_Document_Type
Agenda
CMO_Meeting_Date
3/13/2017
CMO_Effective_Date
3/13/2017
Jump to thumbnail
< previous set
next set >
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
251
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
View images
View plain text
Warm mix asphalt continued to be specified for all the paving projects in 2016 in place of <br />conventional hot mix asphalt; approximately 35,000 tons of warm mix asphalt pavement was <br />placed on capital paving projects in 2016. As explained in the Key Terms section of this report, <br />warm mix asphalt provides environmental and human health benefits as well as a potentially <br />longer lasting product. The National Cooperative Highway Research Program (NCHRP) <br />estimates that there is a CO2 savings of 12 pounds per ton of pavement when using warm mix as <br />compared to hot mix asphalt. The NCHRP also estimates that the use of warm mix asphalt <br />reduces the energy used in the asphalt batch plant by about 30% compared to hot mix asphalt. <br />Reclaimed asphalt pavement (RAP) has been used in Eugene for more than 20 years. Like the <br />State of Oregon, Eugene's current standard specification allows up to 30 percent RAP, by weight, <br />to be used in new asphalt pavement mixes. For several years, local asphalt producers have <br />supplied mixes that maximize the allowed RAP content. <br />Increasing the amount of reclaimed asphalt binder in pavement mixes potentially impacts the <br />quality and longevity of the asphalt pavement, so increasing the allowed reclaimed asphalt binder <br />in mixes needs to be done with consideration as RAP contents greater than 20 to 30 percent is <br />an emerging technology without much research conducted on long-term impacts to the pavement <br />quality. Nationally, multiple organizations are experimenting with increasing the reclaimed asphalt <br />binder content, and Eugene provided pavement samples for research to the Asphalt Pavement <br />Association of Oregon in 2013. <br />In Eugene, typical RAP materials result in a one-to-one replacement of the virgin asphalt cement <br />needed for a typical Level 2,'/2" dense graded asphalt pavement used on residential and collector <br />streets in Eugene. Since the asphalt cement generally makes up about a quarter of the cost of <br />asphalt pavement, reducing the amount of virgin asphalt cement used has the potential to <br />decrease materials costs as well as conserving virgin resources. <br />Based on positive test results on pilot projects constructed in 2013 to increase RAP usage, <br />Eugene continued to select projects to increase the reclaimed binder in asphalt pavements. In <br />2016, the City specified 40 percent binder replacement through the use of reclaimed asphalt <br />materials on Centennial Loop as well as 35 percent binder replacement on several other Bond <br />funded and Local Gas Tax funded roadways. The specification allows flexibility for the contractors <br />to meet the 35 and 40 percent binder replacement value using RAP or a combination of RAP and <br />reclaimed asphalt shingles (RAS) depending on the availability of materials and capabilities of the <br />plant. <br />By its nature, reclaimed asphalt binders are stiffer and pavements that contain higher contents of <br />reclaimed asphalt binders are more susceptible to cracking. To compensate for this potential, the <br />grade of virgin asphalt binder typically used for Eugene paving with higher than 30 percent binder <br />replacement was replaced with a "softer" binder that should better resist cracking. <br />In the use of increased reclaimed binder content, Eugene is on the forefront of this technology <br />and while we are being leaders, we are also proceeding with caution and choosing projects on a <br />case-by-case basis. Typically, we are choosing streets with lower traffic volumes in order to <br />minimize the chances of unintended consequences. <br />
The URL can be used to link to this page
Your browser does not support the video tag.