Form ProjStat
(Rev. 5/2013)
(RTI)
Research Project Statement 17-30
FY 2017 Annual Program
Title:
Methods of Rehabilitating Pavements with Moisture Damaged Asphalt Layers (Deliverable
Based)
The Problem:
Texas has many miles of major flexible highways where a severely moisture damaged (stripped)
asphalt layer exists at some depth beneath the surface. It is not unusual to have 4 inches of
good hot mix asphalt (HMA) over 2 inches of stripped pea-gravel over several inches of good
HMA. These stripped layers lead to surface cracking and greatly reduce the life of any new
asphalt overlay. To permanently repair these problem sections, the conventional wisdom is to
mill down to the solid HMA and then come back with full depth HMA. This is costly and means
that several inches of good materials will be sent to recycled asphalt pavement (RAP) stockpiles
rather than being recycled and reused.
Recent developments in cold in-place recycling (CIR) and cold central-plant recycling (CCPR)
can be considered for addressing this stripping problem while recycling 100 percent of the
existing HMA and placing it as a structurally sound black base layer. Recently, the Virginia DOT
reported success with this approach on a distressed section of IH 81. In that case, they used a
combination of both cement and foamed asphalt to reclaim a deteriorated HMA layer. After four
years in service, that section is in excellent condition under very heavy traffic.
A laboratory study is needed to determine if either CIR or CCPR techniques can be considered
to recycle HMA layers containing severely stripped layers in Texas. Also, a study is warranted to
study the engineering properties of reclaimed layers to determine what level of traffic they can
handle, and if successful guidelines and plans can be developed to construct monitor sections in
Texas.
Technical
Objectives:
1. Review latest techniques in both CIR and CCPR, document nationwide what are recent
successes and failures. Also, review latest technologies available from vendors and identify
advantages and limitations for this application.
2. Visit Districts known to have extensive stripping in existing HMA layers (most in East Texas;
especially, Lufkin, Atlanta, and Bryan). Identify upcoming projects where stripping in the
HMA is a major concern.
3. Test these sections with ground penetrating radar (GPR) to detect potential stripping - core
the section to identify the extent, depth and severity of the stripped layer.
4. Sample the HMA containing the stripped materials and return to laboratory.
5. Conduct a detailed laboratory investigation to determine if it is possible to recycle the existing
HMA to produce a stable high performance black base layer. Conduct advanced materials
characterization tests of rutting and cracking potential. Evaluate alternative stabilizers
including cement, foamed asphalt, and asphalt emulsion.
6. For projects nominated by districts, perform a structural design to recommend an adequate
pavement structure.
Desired
Deliverables:
1. Value of Research (VoR) as a first deliverable that includes both qualitative and economic
benefits (Cost savings analysis).
2. Guidelines for laboratory testing on HMA layers containing stripping.
3. Enhanced Special Specification for both CIR and CCPR.
4. Documentation of the work performed, methods used, and test results.
5. Construction Recommendations.
Proposal
Requirements:
1. Utilize the deliverable based templates (see the appendices provided or in the University
Handbook).
2. Proposals will be considered non-responsive and will not be accepted for technical
evaluation if they are not received by the deadline or do not meet the requirements stated in
Project Statement 17-30
Form ProjStat
(Rev. 5/2013)
(RTI)
RTI’s University Handbook.
3. Proposals should be submitted in PDF format, 1 PDF file per proposal. File name should
include project name and university abbreviation.
Pre-Proposal
Meeting
Information:
Wednesday, March 23, 2016
9:00 – 9:45AM
Austin Riverside Campus
118 E. Riverside Dr.
RTI Conference Room, 1st Floor
Webex Information:
1. Go to
https://txdot.webex.com/mw0401lsp13/mywebex/default.do?siteurl=txdot&rnd=0.9091095085622
569
2. Meeting Number: 735 915 144
3. If requested, enter your name and email address.
4. If a password is required, enter the meeting password: FY17
5. Click "Join".
Teleconference Information:
Provide your phone number when you join the meeting to receive a call back. Alternatively, you
can call:
Call-in toll-free number: 1-866-637-1408 (US)
Conference Code: 951 211 7290
Notifying RTI of
Intent to
Propose:
Notify your University Liaison of your intent to submit a proposal. Your Liaison will provide
information regarding the RFP.
Proposal
Deadline:
Proposals are due to RTI by 4:00 P.M. Central Daylight Time, April 14, 2016. Email
submissions should be sent to rtimain@txdot.gov.
Project Statement 17-30