HomeMy WebLinkAboutMINUTES - 09231986 - 2.1 1-11' 001
TO: BOARD OF SUPERVISORS
FROM: J. MICHAEL WALFORD, PUBLIC WORKS DIRECTOR
DATE: September 23, 1986
SUBJECT: County Rubber Chip Asphalt Chipseal Contract - Response to Board* Referral MR.3
Specific Requests or Recommendations & Background & Justification
RECOMMENDATION
ACCEPT the Public Works Director' s report concerning the administration of the County
Rubber Chipseal Contract.
BACKGROUND
The County has used rubber asphalt chipseal since the late 1970' s as an integral part of
our pavement management program. The process extends the life of deteriorated pavement
about the same length of time, if not longer, than a thin asphalt concrete overlay at 1/2
to 1/3 the cost.
There are two patented processes for manufacturing the soot rubber asphalt. Until a couple
of years ago there was only one process whose rights were owned by International Surfacing
(Crafco) . Last -ear we contracted a portion of ; he work to Arizona Refining to compare
their process.
In comparing the two processes we initially found the Arizona Refining product to be smoother,
have less chip loss, less bleeding, and was more stabile in high temperatures. During a
heat spell last fall a significant problem with bleeding occurred on rubber chipseal which
was placed by International Surfacing at several locations in 1984.
Because these problems had occurred primarily with a product placed in 1984, we Telt that
it could have been a problem with that year's material not meeting specification and not an
inherent problem with International ' s product. We therefore decided this year to advertise
the rubber chipseal project allowing either of the two processes. With tighter inspection
and some specification revisions a more conclusive analysis could be made as to the relative
superiority of one product over the other.
Continued on attachment: X yes Signature:
Recommendation of County Administrator ecommenda ion of Bo d Committee
Approve Other:
Signature(s):
Action of Board on: SEP 2 3 1986 Approved as Recommended Other
Vote of Supervisors I HEREBY CERTIFY THAT THIS IS A TRUE
/ AND CORRECT COPY OF AN ACTION TAKEN
Y Unanimous (Absent ) AND ENTERED ON THE MINUTES OF THE
Ayes: Noes: BOARD OF SUPERVISORS ON DATE SHOWN.
Absent: Abstain: Attested SEP 23 1986
Orig. Div.: PW Maint. Phil Batchelor
cc: Public Works Dir. Clerk of the Board of
Road Engineering - Supervisors and County
Administrator
By DEPUTY
.y.
•
The changes we are instituting this year are as follows:
1) Assign an inspector to monitor the asphalt rubber mixing operation to make sure proper
mixture ratios and temperatures are obtained (bleeding) .
Z) Add an additional roller to the operation to assure proper seating of chips (rock loss) .
3) Changing liquid asphalt to 'a higher viscosity asphalt (bleeding/stability) .
4) Requiring truck mounted distribution trucks versus semi-trucks (smoothness) .
International surfacing was awarded the contract this year. If the problems reoccur with
the revised specifications, we will eliminate their specifications in future projects. We
would like to maintain at least two bidders for the work to keep the price competitive. If
we eliminate International Surfacing, only Arizona Refining can bid.
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