Institute for Transportation

About the research

The design of drilled shafts in Iowa currently relies on the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications. To improve design efficiency at the state level, a series of research projects was conducted to develop the Drilled SHAft Foundation Testing (DSHAFT) database, a regional database facilitating the collection, storage, and efficient access of load test data from Iowa and other states, and to utilize the collected data to establish regional resistance factors that are reflective of the uncertainties associated with predicting drilled shaft capacity under Iowa’s specific geological conditions and construction practices. Resistance factors established in a 2019 study for various resistance prediction methods generally showed improvements over those recommended by AASHTO.

The present research aimed to validate the proposed resistance factors and formulate design recommendations for implementation. To this end, the DSHAFT database was further expanded with additional test data. Additionally, regression analyses were conducted on test data from Iowa to develop local resistance predictions that may provide more accurate estimates of drilled shaft capacity locally. Results from the analysis indicated that a linear correlation between soil parameters and measured unit side resistance was the best fit for most soil types. Moreover, settlement data were collected at several production shafts that were part of a few Iowa DOT bridge replacement projects to evaluate the field performance of drilled shafts designed under the current Iowa DOT guidelines. Various challenges were encountered during the data collection process. Some of the data indicated unexpected negative settlements, and further investigation is needed to develop appropriate conclusions. Design recommendations were formulated based on all findings, and design examples were developed to illustrate the application of the design recommendations.

About the research

The United States has approximately 600,000 bridges and 47,000 miles of interstate highways. More than 75% of bridges and 60% of highways are made of concrete. Concrete production consumes massive amounts of raw materials and energy, and US cement production emits about 67 million tons of carbon dioxide. A key to concrete decarbonization is using low-carbon cement. We propose to formulate, characterize, optimize, evaluate, and implement a new generation, low-carbon, energy-saving, and cost-effective cement made with calcined clay (CC)/natural pozzolan, Type I portland cement (I), and limestone powder (L), called CC·I·L cement. Implementation challenges will be addressed by (1) streamlining the testing process for characterizing raw materials and their blends, (2) using machine-learning techniques to optimize cement composition and predict performance, (3) developing prediction models for hydration and adiabatic temperature rise via software modification, and (4) conducting both laboratory and field investigations to comprehend performance. A roadmap will be developed defining goals, outcomes, and milestones for implementing CC·I·L in future transportation infrastructure.

About the research

This project is a task order under the main Federal Highway Administration (FHWA)-sponsored project, “Infrastructure Research and Technology Deployment Program.”

Past regional bridge load rating peer exchanges conducted by the FHWA from 2014 to 2019 proved effective to gain an understanding of the load rating practices used by state departments of transportation (DOTs). The exchanges helped make known the best practices and technologies being used for load rating bridges, posting bridges, and issuing permits. The success of these exchanges and the continual evolution of practices and technology coupled with newly imposed requirements provide reason for additional peer exchanges, which are intended to include representatives from all DOTs.

About the research

To extract the necessary data and features from the existing inspection reports, a manual process is currently in place. This means that, even for a simple query, the engineer/staff member in charge needs to browse several pages, locate appropriate details, determine quantities, and note down the required information. This task becomes further demanding if the scope of the query is extended to several bridge elements, involving a post-processing of various sources of inspection information. However, with the advancements made in machine learning and artificial intelligence (ML/AI), new opportunities have emerged to move from a manual to an automated process for data and feature extraction from bridge plan sets and inspection reports. Thus, this research project aims to develop the first-known computational platform to automate the process of extracting defects from available inspection records with the ultimate goal of quick delivery of high-quality information about the condition state of bridges. The main features of this platform include distinguishing different physical objects, determining their boundaries and dimensions, detecting various signs of defect, and finally providing qualitative and quantitative assessments of defect for the bridge elements of interest in desired output formats. Further to the listed features, an important capability of this platform is that, after training and quality control, it can work with no immediate supervision, minimizing the time and effort required to plan preventive and corrective actions for bridge structures.

About the research

The objectives of this task order are as follows:

1. Develop a synthesis of knowledge on traffic signal change and clearance intervals, identify research gaps, develop a research plan, and evaluate potential data collection alternatives.
2. Provide a report, and companion database to characterize the current state of knowledge and practices related to traffic development and implementation of traffic signal change and clearance intervals.

“This project is a task order under the main FHWA-sponsored project DTFH61-16-D-00053, in which LEIDOS, Inc. is the Lead.” 

About the research

The Process Document was developed to help agencies manage and evaluate work zone activities and document the lessons learned. Its objective is to outline a structured post-construction evaluation process that uses a feedback loop to help evaluate and improve performance during the construction phase and generate lessons learned for future use.

The scope for the work was as follows:

• Define a structured review process that includes evaluation
• Define a feedback loop to document and mitigate project issues and generate lessons learned
• Develop a structure for lessons learned documentation
• Demonstrate the implementation of lessons learned in example projects

The four appendices (A through D) at the end of the Process Document were designed to be easily accessed at a later date. Appendix C provides a sample Lessons Learned form that readers can adapt and use on their projects.

The Discussion Facilitation Guide is a companion document to the Process Document, and the purpose is to provide resources to facilitate discussion during training. This document provides a training discussion outline with recommended steps for facilitation. Everything mentioned in this companion document is a suggestion and can be adjusted accordingly.

About the research

This project is a task order under the main Federal Highway Administration (FHWA)-sponsored project, “Infrastructure Research and Technology Deployment Program.”

The Utah Department of Transportation (UDOT) coined the phrase, “good roads cost less.” UDOT emphasized the long-term financial savings that agencies gain when they keep roads in good condition through timely preservation and maintenance.

The Center for Transportation Research and Education (CTRE) team proposes to demonstrate the effects of bridge and pavement conditions on a wide array of system performance objectives. The team will demonstrate how state departments of transportation (DOTs) can, in their transportation asset management plans (TAMPs), enhance performance in all areas by sustaining a state-of-good-repair (SOGR) for National Highway System (NHS) pavements and bridges. The CTRE approach also will show how a TAMP can communicate to stakeholders the linkages between the SOGR and achievement of system performance goals.

About the research

The overall goal of this project is to provide a variety of expert technical support services and technology transfer activities to the Federal Highway Administration’s (FHWA’s) Construction Management Team (CMT). The project includes assisting the CMT in its efforts to advance the industry-wide adoption of innovations that accelerate the delivery of pavement and bridge construction projects by providing appropriate information and training to state and local highway agencies, consultants, materials suppliers, research/academic institutions, and other stakeholders through workshops, conferences, equipment demonstrations, presentations, technical publications, and web-based training.

This project supports several task orders. They include the following:

• Technical Support Service Centers for 3D Engineered Models in Construction and Slide in Bridge Construction Activities
• Training and Marketing in Support of Every Day Counts Initiatives and Other Program Initiatives
• Virtual Workshop Support
• Development of Web Based Training (WBT) on Constructing PCC Pavement Preservation Treatments
• Support of Every Day Counts Four (EDC-4) Initiative: Development and Facilitation of Peer-to-Peer Exchanges for Pavement Preservation How and Update and Modernize the Pavement Preservation Checklist Series
• Technical Assistance for Advanced Survey and Modeling Technologies and Practices
• Reassess and Update the FHWA Pavement Preservation Research Roadmap
• FHWA Unmanned Aerial System Tech Brief Development and Every Day Counts Round 5 Support
• Advancing the Development and Deployment of BIM-Infrastructure

About the research

The purpose of this cooperative agreement is to further an ongoing concrete pavement technology program, which includes the deployment and transfer of new and innovative technologies and strategies to advance concrete pavements and improve pavement performance.  A list of the recent deliverables is available here.

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Project Details

Work areas for this project are as follows:

• Deployment of new, cost-effective designs, materials, recycled materials, and practices to extend the pavement life and performance and to improve user satisfaction—with a focus on concrete recycling and the use of industrial waste or byproducts in concrete pavement mixtures
• Reduction of initial costs and life-cycle costs of pavements, including the costs of new construction, replacement, maintenance, and rehabilitation—with a focus on strategies and technologies for rehabilitation and maintenance
• Deployment of accelerated construction techniques to increase safety and reduce construction time and traffic disruption and congestion—with a focus on the use of performance engineered concrete mixtures for accelerated construction without compromising durability
• Deployment of engineering design criteria and specifications for new and efficient practices, products, and materials for use in highway pavements—with a focus on further development and implementation of the American Association of State Highway and Transportation Officials (AASHTO) PP 84-17 specification for Performance Engineered Concrete Mixtures
• Deployment of new nondestructive and real-time pavement evaluation technologies and construction techniques—with a focus on technologies for construction quality assurance and quality control
• Effective technology transfer and information dissemination to accelerate implementation of new technologies and to improve life, performance, cost effectiveness, safety, and user satisfaction—with a focus on partnering with state departments of transportation (DOTs) and industry to advance these innovative technologies

About the research

This project is a task order under the main Federal Highway Administration (FHWA)-sponsored project, “Technical and Support Services for the FHWA Construction Management Team.”

Whether a highway pavement is constructed using concrete or asphalt, the structure will deteriorate over time because of traffic loading and environmental factors. Technologies such as thin overlays, micro surfacing, slurry seals, and chips seals are some pavement preservation treatments applied to asphalt pavements. Technologies such as full depth patching, partial depth patching, dowel bar retrofitting/ cross-stitching, and diamond grinding are some pavement preservation treatments applied to concrete pavements. These treatments can be very effective in extending the performance life of pavements if applied at the right time on the right project with quality construction and materials.

The Every Day Counts Four (EDC-4) Pavement Preservation “How” initiative accelerates the national deployment of underutilized proven technologies and techniques to construct quality pavement preservation treatments with quality materials. This includes the use of sustainable quality materials and methods, construction equipment, and assuring a quality workforce to construct these surface treatments.

The objective of this task order is to assist in the peer-to-peer exchange of lead state and exploring state, to exchange knowledge about how to effectively implement Pavement Preservation “How”. The focus of the exchange will be based upon the concepts, capabilities, and applications of constructing pavement preservation treatments with quality materials for transportation agencies, contractors, consultants, and FHWA staff.

The objectives of the task order are:

1. Develop and maintain a database of lead states approach, strategies, and strengths for Pavement Preservation “How” for the life of this task order;
2. Identify the needs and desires of exploring states to learn how to implement Pavement Preservation “How”. Align the exploring agency needs with a lead agency strength. Organize, facilitate, and accompany a peer-to-peer exchange between the two agencies;
3. Develop tech briefs for each peer-to-peer exchange that contain example guiding documents, specifications, work flows, and lessons learned to help other states adopt quality construction and materials for pavement preservation;
4. Review and update the current Pavement Preservation Checklist series;
5. Develop a modernized version of the Pavement Preservation Checklist series to include a smart phone app; and
6. Produce and embed brief videos demonstrating the key components of each checklist treatment.