Research Project Statement 16-34
FY 2016 Annual Program
Form ProjStat
(Rev. 5/2013)
(RTI)
Title:
The Problem:
Technical
Objectives:
Use of Lasers for Laboratory Measurements of Aggregate Shape, Angularity, and Texture
Aggregate angularity is important for achieving stone-on-stone contact and resistance to deformation in hot mix asphalt mixtures. Aggregate texture affects the friction developed at the tire-pavement interface, and is thus important to driver safety. These aggregate properties are measured in the laboratory using the Aggregate Image Analysis System (AIMS), which is based on analyzing the images of aggregate samples taken with a digital camera to determine aggregate shape, angularity, and texture. TxDOT owns and operates the current camera-based imaging system; however, the current system may provide misleading results for aggregates of various shades of color when they are scanned. This is significant because it may lead to erroneous rankings of materials. Texture measurements are commonly made using lasers for pavements in-service and for specimens compacted in the laboratory or taken from field sections; however, the application of lasers as an alternative to image analysis is not used in turnkey systems for characterizing aggregate shape, angularity, and texture. There is a need to investigate the application of these optical sensors for measuring aggregate profiles to determine shape, angularity, and texture, and to compare these measurements with those from the image analysis method.
This research will test the application of laser sensors for measuring aggregate shape, angularity, and texture as an alternative to the image analysis method using a digital camera, such as in AIMS, which is currently used by TxDOT. This proposed project will:
1.
Provide a proof-of-concept to demonstrate the feasibility of using laser optical sensors to determine aggregate shape, angularity, and texture. It will include a review of existing methods to compare the strengths, limitations, and costs between the different systems used in practice.
2.
Develop a prototype laser-based system and demonstrate its application on a limited range of aggregate samples. This demonstration will compare test results from the prototype with corresponding data using AIMS.
3.
Provide recommendations for implementing the product of this research project.
Desired
Deliverables:
1.
Value of Research (VoR) that includes both qualitative and economic benefits.
2.
A report to document the development of a prototype system for aggregate laser testing, and the proof-of-concept demonstration of this prototype.
3.
Comparative evaluation between this system and the AIMS, and recommendations for product implementation.
4.
User’s guide to the laser-based system developed in this project.
5.
Version 1.0 system for aggregate laser testing.
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 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.
Project Statement 16-34

Form ProjStat
(Rev. 5/2013)
(RTI)
Pre-Proposal
Meeting
Information:
Proposal
Deadline:
Friday, September 11, 2015 9:00 – 12:00
Austin Riverside Campus
118 E. Riverside Dr.
ENV Conference Room, 1st Floor, 1B1A
Webex Information:
Join the online meeting:
Go to:
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: 1-866-6371408 (US)
Conference Code: 199 125 9183
Proposals are due to RTI by 4:00 p.m. Central Time, October 12, 2015. Email submissions should be sent to rtimain@txdot.gov.
Project Statement 16-34