Link for downloading the Poster Session Brochure: 2019-CTR-Symposium-Poster-Handout-Final
An Adaptive Signal Control Method Involving the Lighthill Whitham Richards Model Using Mixed Integer Linear Programming
An adaptive signal control framework for a single intersection is developed. Traffic volume prediction and signal optimization are two crucial components of adaptive control methods. This paper proposes both models based on the Barron-Jensen/Frankowska (B-J/F) solution to the Lighthill-Whitham-Richards (LWR) model. This framework is applicable for the rapidly changing traffic conditions since it depends on the current traffic state of the network instead of the assumptions about the arrival process and the correlation of the flows in the time dimension. To reduce the computation time to make the proposed method practical, the MILP is decomposed into two parts and an approximated algorithm is developed to solve them. Finally, this paper compares the new method to the critical lane flow ratio method which is a commonly used strategy. The delay per vehicle resulting from the new method is reduced under various degrees of traffic congestion.
Research sponsor: UTC
By: Hao Liu, Amber Chen, and Randy Machemehl
PI: Randy Machemehl
Presenter: Hao Liu
Construction Engineering and Inspection (CE&I) Staffing
Discussions with subject matter experts from TxDOT indicate that spending too little on Construction Engineering and Inspection (CE&I) can lead to quality issues, however spending too much could lead to inefficient use of limited public resources. CE&I costs comprised between 3.2% and 4.4% of total construction costs every year between 2005 and 2015 at TxDOT. This study provides an overview of CE&I costs incurred by TxDOT between 2001 and 2017 to identify optimal allocation of resources (and consequently costs) for CE&I functions at the project level. The results indicate that the CE&I costs (when expressed as a percentage of construction costs) have an inverse relationship with construction cost and vary based on the project type. This study additionally highlights a need for careful examination of costs for projects larger than $1 million whose classification contains the term “miscellaneous” as the use of such a generic category can result in misrepresentation of costs.
Research sponsor: TxDOT
By: Julie C. Faure, Kasey M. Faure, Nabeel Khawja and William J. O’Brien
PI: William J. O’Brien
Presenter: Julie C. Faure
Cross-Functional Planning of Projects in TxDOT: Sandbox Tool
The Texas Department of Transportation (TxDOT) is required to develop Transportation Improvement Programs that align with the state-wide goals of Texas. In order to achieve this, multiple functional groups (maintenance, capital, safety, operations etc.) are tasked with developing group-specific budget allocation programs. Since these functional groups often propose projects for assets on the same network, there is always a risk of having spatial conflicts in the list of candidate projects across functional groups. However, the heterogeneity in the legacy information systems used by different functional groups can make it difficult to identify these conflicts. To address this issue, a planning (Sandbox) tool was developed in this study to provide a collaborative platform to support cross-functional planning of highway projects. The developed tool helps in identifying spatial-temporal conflicts at early stages of planning and provides a structured documentation for conflict resolution.
Research sponsor: TxDOT
By: Chirag Kothari, Jojo France-Mensah, William J. O’Brien and Nabeel Khwaja
PIs: William J. O’Brien and Nabeel Khwaja
Presenter: Chirag Kothari
A Data-Driven Methodology for Prioritizing Traffic Signal Retiming Operations
Signal retiming is one of the chief responsibilities of municipal transportation agencies, and is an important means for reducing congestion and improving transportation quality and reliability. Leveraging a data-driven approach to prioritizing signal retiming operations could better optimize use of agency resources. This study presents a methodology for utilizing probe-based speed data to rank the performance of traffic signal corridors for retiming purposes. This methodology is then demonstrated in an analysis of seventy-nine traffic signal corridors maintained by the City of Austin, Texas.
Research sponsor: City of Austin Transportation Department
By: Michael R. Dunn, H. Westerfield Ross, C. Baumanis, N. Ruiz Juri, R. B. Machemehl, J. Wall, J. Lammert, J. Duthie
PIs: Natalia Ruiz Juri and Randy Machemehl
Presenter: Natalia Ruiz Juri
Determine Use of Alternative Retroreflective Pavement Markers (RPMs) on Highways with Centerline Rumble Strips and Winter Weather Pavement Marking Improvements
The use of snow plows in northern Texas frequently results in loss of retroreflective pavement markers (RPMs). The loss of RPMs is not only costly, but also creates unsafe driving conditions during inclement weather. Pavement sections in these districts often use a center-line rumble strip for safety. Traditionally, these rumble strips have precluded the use of metal-encased RPMs (i.e., snow-plowable RPMs). This project evaluates two innovative approaches to arrive at a cost-effective and snow-plowable configuration for roadways containing rumble strips: (i) use of existing commercially available RPMs inset within the trough regions of rumble strips (referred to as rumble inserts) and (ii) use of polymers with reflective beads similar to raised stripes, except inside the rumble strip recess at the appropriate height required for safety (referred to as rumble stripe). The work plan explores variations of both options as well as possible design adjustments to accommodate retroreflection requirements while preventing loss of RPMs due to snow plows.
Research sponsor: TxDOT
See TxDOT Research Project 6995 for more information.
By: Vivek Turkar, Raissa Ferron, Micheal Rung, David Fowler
PI: Raissa Ferron
Presenter: Vivek Turkar
Develop A Tool to Automate Damage Claim Process
This study develops an Excel-based tool to automate Damage Claim (DC) process for Austin District. A DC usually consists of multiple forms, photos, and invoices that need to be submitted to Finance Division in order to claim money to repair TxDOT infrastructure after an accident. This tool saves time of maintenance section staff and improves efficiency in preparation of DCs by 1) having automatic checks on missing/incomplete information, 2) archiving digital files in an organized structure, and 3) helping Austin District to track the DCs being filled and missing. Stage 1 Tool has already been implemented and current being used. Feedback from both Austin District and Area Offices indicated that this tool would help the District to increase and track the number of claims being filled and claim more money from insurance companies.
Research sponsor: TxDOT – Austin District
By: Oscar Galvis, Zhe Han, Mike Murphy, Zhanmin Zhang
PI: Zhe Han
Presenter: Oscar Galvis
Enhancing Road Weather Management during Wildfires and Flash Floods through New Data Collection, Sharing, and Public Dissemination Technologies
This project focuses on enhancing road weather management during wildfires, flash floods, and other extreme weather through data collection, sharing, and public dissemination technologies. Products include research and findings on best practices in roadway operations, a curated data catalog relevant to roadway management, and the use of sensors to aid in operational and traveler decision-making. Further implementation requires integrating sensor data into Texas Department of Transportation IT architecture and existing software systems, properly creating accessible data for analysis and validation purposes, refining methods to improve sensor data coverage and reliability, defining and continuing to track performance metrics, and developing further processes for dissemination. The findings, lessons learned, sensors, and data analytic techniques were demonstrated in two workshops conducted in Abilene and Austin, TX, to familiarize practitioners on key concepts needed for conducting a successful sensor deployment and data analytics practice.
Research sponsor: TxDOT
See TxDOT Research Project 9053-01 for more information.
By: Kenneth Perrine, Chandra R. Bhat, Christian Claudel, Natalia Ruiz Juri, Kamryn Long, Abduallah Mohamed, Tian Lei, Kamran Khan, and Jonathan Butler
PI: Chandra R. Bhat
Presenter: Michael Moore
Evaluate Economic Impacts of Freight Corridor Projects
One project may help improve the traffic conditions at the local level, but the group effects of a set of projects on the entire road network might be different due to shifts in modes and routes. Our project develops a methodology to measure the network-wide economic effects of a whole series of transportation projects or interventions. It can be applied to questions of local, corridor, or statewide scope, and can deal with different types of projects, such as tolling, expansion, and upgrading.
Research sponsor: TxDOT
By: Rydell D. Walthall, Ruohan Li, Nan Jiang, Michael Walton
PI: Michael Walton
Presenter: Rydell D. Walthall
Expanding Access to & Discovery of Research Information
Since 1948, the Texas Department of Transportation (TxDOT) has cooperated with state-funded universities to sponsor research and implement innovative ideas, improving the safety and performance of Texas’s transportation networks. As of FY19, there were over 120 active research projects at 10 Texas universities under the program. Overseen by the Research and Technology Implementation Division (RTI), the TxDOT Research Library serves as the official repository for all publications produced through the cooperative research program. The library is a central location for reference materials that support transportation research and TxDOT in general. The library provides document delivery, literature search services, and a robust online search tool for users around the world. Staff strive to help TxDOT professionals and researchers efficiently locate critical, relevant research for their needs.
Research sponsor: TxDOT
See TxDOT Research Project 9902-17 for more information.
By: Renee Suaste, Mike Murphy, Keyvn Barnes, Michael Nugent
PI: Mike Murphy
Presenter: Michael Nugent
Factors Affecting Microcracking in Pre-Stressed Concrete Girders
Unexplained microcracks have been found in in-service pre-stressed concrete girders across Texas. As these cracks are a relatively new phenomenon, there are concerns about loss in durability and increased corrosion of the pre-stressing strands and rebar, as the cracks can provide easy access to deleterious substances. This research aims at quantifying the relationship between microcracking (width, density and depth) and loss in durability and strength and generate a model to predict the remaining service life of these girders. The results from this study are expected to facilitate an increase in the understanding of the temporal behavior of microcracks in real world specimens and the resulting loss in durability and strength of low water-cementitious material concretes.
Research sponsor: TxDOT
See TxDOT Research Project 6922 for more information.
By: Savitha Sagari Srinivasan and Raissa Douglas Ferron
PI: Raissa Douglas Ferron
Presenter: Savitha Sagari Srinivasan
Incorporating Wildlife Crossings into TxDOT’s Project Development, Design and Operations Processes
Each year close to 8,000 crashes involving wild or domestic animals are reported in Texas. Roughly 20 people die each year on Texas roadways in these crashes, many more sustain injuries, and thousands of animals lose their lives. To reduce AVCs, it is important to provide opportunities for wildlife to cross beneath or above roadways via special crossing structures. TxDOT research project 0-6971 summarizes national and state-level efforts to reduce animal-vehicle conflict, analyzes Texas’s AVC data, explains how to identify AVC hot spots, and provides benefit-cost ratios for various AVC mitigation efforts across the TxDOT highway system. The project also recommends specific language modifications to 18 TxDOT manuals and provides a new manual on wildlife crossing structures. The project findings demonstrate that data-driven, carefully planned, and well-designed wildlife crossing structures can enhance traffic safety significantly, are cost-effective, and help ensure that TxDOT can play a meaningful role in preserving human and animal lives and property for the benefit of current and future Texans.
Research sponsor: TxDOT
See TxDOT Research Project 6971 for more information.
By: Nan Jiang, Lisa Loftus-Otway, Patricia Cramer, Devin Wilkins, Noah Oaks, Kara Kockelman and Mike Murphy
PI: Nan Jiang
Presenter: Nan Jiang
Modeling Individuals’ Willingness to Share Trips with Strangers in an Autonomous Vehicle Future
From a travel behavior perspective, two essential elements to the adoption of dynamic ridesharing services (also known as pooled ride-hailing or pooled shared autonomous vehicles (PSAV)) within the emerging transportation AV landscape are individuals’ acceptance of increased travel times associated with pick-up/drop-off of other passengers and their approval of strangers sharing the same vehicle. In this AV environment context, the current study examines individuals’ values of travel time (VTT) and develops the notion of willingness to share (WTS), which represents the money value attributed by an individual to traveling alone compared to riding with strangers. Our results show that PSAVs may have a large market penetration potential, especially for commute trips, as long as operated efficiently with minimal detour and pick-up/drop-off delays. This has substantial implications for addressing urban traffic congestion and improving safety, and should be of interest to TP&P and PTN divisions, in addition to TxDOT Districts.
Research sponsor: UTC, Cintra, CAPES and the Brazilian Government
By: Patricia S. Lavieri and Chandra R. Bhat
PI: Chandra R. Bhat
Presenter: Aupal Mondal
A Multivariate Model of Ride-Hailing Trip Characteristics in Dallas
The current study characterizes ride-hailing usage by investigating four dimensions of ride-hailing trips (purpose, time-of-day, companionship, and mode substituted, which includes the generation of new trips) using survey data from Dallas-Fort Worth (DFW), Texas. The results indicate that ride-hailing can indeed provide more access to activity opportunities for individuals who do not own vehicles and/or those with limited driving capabilities. Thus, ride-hailing can assume a welfare role, but fares would need to be revisited to fit the needs of these more financially challenged segments of our society. More generally, the study reveals that ride-hailing has the potential to fundamentally change the spatial, temporal, and modal activity-travel landscape of individuals. It is important for planning agencies to collect data on ride-hailing and incorporate ride-hailing behavior (and mobility-on-demand features) within their travel modeling systems. The study should be of interest to TP&P and many other TxDOT divisions/districts.
Research sponsor: UTC, Cintra, CAPES and the Brazilian Government
By: Patricia S. Lavieri and Chandra R. Bhat
PI: Chandra R. Bhat
Presenter: Felipe Dias
Revisiting Performance Metrics in Performance Grade (PG) Asphalt Binders and Recycled Asphalt
Asphalt binder is the most critical component of a flexible pavement that directly dictates its durability and serviceable life. The current Performance Grade (PG) specifications were developed almost three decades ago and do not address the influence of chemical and polymer additives and other waste products and extenders used by the binder industry. These specifications also do not address the properties in the context of the increased use of reclaimed asphalt pavements (RAP). This study presents the findings from a recent study that focused on identifying and developing metrics that are more representative of the actual performance of virgin and reclaimed asphalt binders in the field.
Research sponsor: TxDOT, UTC
See TxDOT Research Project 6925 for more information.
Download PDF of poster [change to link from spreadsheet].
By: Ramez Hajj, Angelo Filonzi, and Amit Bhasin
PI: Amit Bhasin
Presenters: Angelo Filonzi and Satyavati Komaragiri
Synthesis of Precast Column Designs for Texas Bridges
There is an increasing interest in prefabrication of bridge elements to accelerate bridge construction. To date, prefabrication of bridge columns has been very limited as compared to bridge superstructures and bent caps. This project shall evaluate the state of the art of national research and construction projects involving precast columns for bridges. The primary objectives of this project shall be to: (a) review and synthesize published literature and current DOT practice on precast columns, (b) compile lessons learned from previous projects and studies, (c) evaluate the suitability of existing precast column solutions for Texas bridges, and (d) determine criteria for the selection of precast columns over conventional cast-in-place solutions for Texas bridges. This project shall provide technical recommendations for implementing precast columns in Texas, which will ultimately contribute to reduce construction costs, time, and disruptions.
Research sponsor: TxDOT
See TxDOT Research Project 6978 for more information.
By: Ghassan Fawaz, Oguzhan Bayrak, and Juan Murcia-Delso
PI: Juan Murcia-Delso
Presenter: Ghassan Fawaz
Understanding the Impacts of Freeway Lane Closures through Data: A Combined Analysis of NPMRDS and Fixed-Sensor Data
This paper explores the use of probe-based speed data to understand the evolution and length of queues caused by freeway lane closures. The proposed methodology addresses some limitations related to the length of the segments for which speeds are provided, and is validated with spot-speed data from work zone trailers on the I-35 corridor in Austin, Texas. Traffic volumes are also critical in quantifying the cost of lane closures. However, volumes are often available only at limited locations or for specific time periods. This work presents an approach to developing a speed/flow relationship using NPMRDS and limited fixed-sensor data. The relationship may be used later to estimate traffic volumes by time of day at other locations based only on NPMRDS speeds. Numerical analyses using traffic counts on I-35 suggest that the proposed technique is accurate and that it improves upon similar methodologies that use NPMRDS data.
Research sponsor: TxDOT
By: Amber Chen, Yun Li, Heidi Westerfield Ross, Tengkuo Zhu, Natalia Ruiz Juri
PI: Natalia Ruiz Juri
Presenter: Amber Chen
Virtual Reality Potential Applications
Computer visualization (3D and 4D) of transportation construction project has proven exceptionally valuable for analyzing complex engineering information, communicating internally for project teams or externally for the public and other stakeholders, and education for the public. An emerging technology, Virtual Reality (VR) is a new visualization tool that has potential to be very valuable for transportation construction projects. Virtual Reality (VR) allows users to experience 3D models at human scale through a head-mounted display (HMD). Users can have varying degrees of control over their movements inside the 3D model in a VR environment and various ways to interactive with the 3D model. The technology has become robust enough that the mind accepts, to a certain degree, that what a user is seeing is real. . In order to generate ideas from transportation engineers, stakeholders, and the public, the authors created a proof of concept VR model to experience and generate ideas. For this proof of concept the authors created a virtual construction site for people to explore.
Research sponsor: TxDOT
By: Cameron Schmeits and Nabeel Khwaja
PI: Nabeel Khwaja
Presenter: Cameron Schmeits