Laboratory and field performance measurements to support the implementation of warm mix asphalt in Texas (open access)

Laboratory and field performance measurements to support the implementation of warm mix asphalt in Texas

An objective of this study was to monitor the performance of more than 10 warm mix asphalt (WMA) projects in the state. Several WMA technologies were included in the study (foaming, Advera, Evotherm, Rediset, Sasobit) and it was determined that performance of the warm mix was comparable to hot mix. In addition, mix from two warm mix projects were subjected to different curing times and temperatures and then evaluated for mixture volumetrics and performance properties. Results from this study lend support to the current procedures the Texas Department of Transportation has adopted.
Date: July 2012
Creator: Estakhri, Cindy K.
System: The Portal to Texas History
Full-depth reclamation : new test procedures and recommended updates to specifications (open access)

Full-depth reclamation : new test procedures and recommended updates to specifications

Rehabilitating an old pavement by pulverizing and stabilizing the existing pavement is a process referred to as Full Depth Reclamation (FDR). The stabilized layer becomes either the base or sub-base of the new pavement structure. This process has been used widely for over 20 years in Texas to strengthen and widen structurally inadequate pavement sections. This project developed guidelines on successful FDR practices, developed training materials, and identified areas where improvements to current practices are required. To improve the FDR process, this report includes the following enhancements: (1) As current laboratory testing to select the optimal type and amount of stabilizer takes too long and requires too much material, continue to run parallel testing with the small sample test protocols proposed in this report; (2) Use the falling weight deflectometer (FWD) during construction to validate that the design assumptions are being met; (3) Implement the proposed bond test to select the optimum prime material and amount needed to effectively bond the base to the surfacing materials; (4) Modify the specifications to avoid working in freezing conditions; and (5) Consider implementing the other modifications to specifications proposed in this report.
Date: July 2012
Creator: Scullion, Thomas; Sebesta, Stephen; Estakhri, Cindy K.; Harris, Pat; Shon, Chang-Seon; Harvey, Omar et al.
System: The Portal to Texas History
Performance comparison of various seal coat grades used in Texas (open access)

Performance comparison of various seal coat grades used in Texas

This report documents research efforts to provide comparative quantitative performance information for various grades of seal coat aggregate available in the Texas Department of Transportation standard specifications. Length of service before replacement and level of noise generated at the tire-pavement interface were the primary focuses of the relative performance evaluations. The additional service life possible from seal coats with larger aggregate and higher asphalt application rates is compared to the additional cost generally associated with these larger aggregate seal coats. The comparative performance information combined with knowledge gathered from numerous department field engineers resulted in the development of guidelines for optimal seal coat grade selection.
Date: July 2012
Creator: Krugler, Paul E.; Wirth, John E.; Estakhri, Cindy K.; Freeman, Thomas J.; Wikander, John P. & Wimsatt, Andrew J.
System: The Portal to Texas History
Development of Texas Transportation Institute's asphalt compaction monitoring system (open access)

Development of Texas Transportation Institute's asphalt compaction monitoring system

"In recent years, the Texas Department of Transportation has made significant progress with the development and implementation of new technologies to measure the uniformity of new hot mix asphalt layer construction. In Project 0-6992, researchers took this check one step further by developing an accurate global positioning system tracking system for compaction rolling so that the compaction effort applied can be monitored for 100 percent of the new surface. This report presents details of the hardware and software developed in this study. The system was field tested on a number of new overlay projects in Texas."
Date: July 2012
Creator: Liu, Wenting; Scullion, Thomas & Kassem, Emad
System: The Portal to Texas History
Accommodating oversize and overweight loads: technical report (open access)

Accommodating oversize and overweight loads: technical report

"In this report the research project resulted in a statewide map recommending primary and alternate Oversize/ overweight (OS/OW)route networks for the most common origins and destinations based on historical Motor Carrier Division data. Keeping strategic routes open for OS/OW loads and minimizing the number of reroutes along the way will reduce the impedance and unknowns in this critical segment of the motor carrier industry."
Date: July 2012
Creator: Middleton, Daniel R.; Li, Yingfeng; Le, Jerry & Koncz, Nicholas
System: The Portal to Texas History
Development of guidelines for triple left and dual right-turn lanes :  technical report (open access)

Development of guidelines for triple left and dual right-turn lanes : technical report

Report regarding the development of geometric and signal design guidelines for triple left-turn lanes and dual right-turn lanes and then evaluatues the safety of such sites in Texas.
Date: July 2011
Creator: Cooner, Scott A.; Ranft, Stephen E.; Rathod, Yatin K.; Qi, Yi; Yu, Lei; Wang, Yubian et al.
System: The Portal to Texas History
Development of the Texas Revenue Estimator and Needs Determination System (T.R.E.N.D.S.) model :  FY 2010 activities (open access)

Development of the Texas Revenue Estimator and Needs Determination System (T.R.E.N.D.S.) model : FY 2010 activities

Report that recaps the continued development of the Texas Revenue Estimator and Needs Determination System model.
Date: July 2011
Creator: Ellis, David; Glover, Brianne; Norboge, Nicolas & Zhi, Yuan
System: The Portal to Texas History