CONSTRUCTION, Geotechnical and Structures Division

Developing sustainable, resilient and efficient solutions for the design, construction and evaluation of transportation structures.

What We Do

Develop Knowledge Tools and Methods for Construction Engineering and Management

We develop knowledge tools and methods to add value to construction project development and processes. Our focus is on methodologies to manage risk, generate good decisions, optimize project delivery and systems, assess the performance of constructed facilities (both public and private), manage project financing and contingencies, and determine how to best maintain and renew these facilities.

Investigate and Develop Geotechnical and Geoenvironmental Solutions

We investigate and develop solutions for shallow and deep foundations for bridges and other structures, retaining walls, slope stability, and geoenvironmental issues including the detection and remediation of soil contaminants. Our group has extensive experience in shrink-swell soils and unsaturated soils, scour and erosion, marine geotechnics, energy geotechnics, risk analysis and management, as well as numerical simulations and large-scale testing.

Design and Evaluate Structural Systems and Components

We develop new and innovative methods to analyze, design, construct, maintain, and manage the diverse types of structures and structural components that are part of the nation’s transportation network. These structures include many types of bridge structures and components including bridge decks, girders, bent caps, piers and abutments, along with sign bridges and traffic signal structures.

Full-Scale Testing and Field Investigation

We test structural and geotechnical components and systems at both large-scale and full-scale. Our laboratories include the state-of-the art facilities in the Center for Infrastructure Renewal and the National Geotechnical Experimentation Site. We also investigate bridge structures on site to evaluate structural and foundation performance, including issues related to deterioration, load capacity and foundation scour. These studies are complemented by testing to characterize materials along with advanced data acquisition, assessment and analysis techniques.

Share and Inform

We are passionate about sharing the knowledge gained through our research with the broader engineering community (when allowed by the sponsor). Reports, papers, workshops and presentations are just a few ways we leverage research findings to educate the professional community, thus enhancing the impact our research can have on the users of the transportation network.

A black SUV drives on a road beneath a white concrete bridge on a partly cloudy day.

Our Focus Areas

Develop and Innovate

Develop new and innovative methods to design, construct, maintain and manage the diverse types of structures and structural components that are part of the nation’s transportation network.

Analysis and Design

Analysis and design of reinforced concrete, prestressed concrete, steel and composite steel-concrete structures.

Structural Testing and Assessment

Structural testing and assessment of components and systems in the laboratory and the field.

Evaluation and Monitoring

In situ monitoring and evaluation of structural condition over time.

Energy Geotechnics

Nuclear waste disposal at great depth, geothermal energy, and unsaturated soils.

Bridge Scour and Erosion

Assessment and monitoring of bridge scour and erosion.

Project Forecasting and Execution

More accurate forecasting of construction project cost at completion and duration at completion throughout project execution. Rational determination of project contingencies (management reserves) and tracking of contingencies during project execution.

Project Delivery

Project delivery methods and systems, construction warrantees and guarantees, construction project acceleration, concurrent engineering and construction.

Decision-Making, Optimization and Managing Risk

Effects of risk aversion on project management decisions. Methodologies to manage risk and risk allocation for public/private build-own-operate-transfer (BOOT) projects.

Foundations and Retaining Walls Testing

Field evaluation, large-scale testing, numerical simulations of foundations and retaining walls, risk analysis.

Our Work

Utilization of UHPC Bridge Superstructures in Texas

The use of ultra-high-performance concrete (UHPC) in Texas bridges has the potential of producing substantial improvements to bridge construction. This project aimed to identify the applications in which the use of UHPC can be leveraged to develop new structural systems. TTI conducted an analytical feasibility study to identify the material properties for a nonproprietary UHPC mixture design to deliver the optimal design benefits; applied those properties to develop such a non-proprietary concrete mixture design; and conducted full-scale and material-level experiments to study whether the use of ordinary reinforcing bars could be eliminated or minimized in UHPC applications.

Development of a Continuous for Live Load Prefabricated Steel Accelerated Bridge Construction (ABC) Unit for Texas Bridges

TTI developed a system where prefabricated steel ABC unit perform continuous for live load in which the system was easily constructible, fast to assemble, durable long-term, safe, and cost-effective. By evaluating literature, experience of other state departments of transportation and other agencies and by evaluating behavior of related TxDOT bridges through visual inspection and monitoring, TTI facilitated an Industry Review Panel (IRP) workshop to select the top three best system designs. Full-scale laboratory testing and analytical parametric studies were conducted on all three designs, results of which were discussed with the IRP and TxDOT, leading to the selection of the final system shall be selected. TTI developed full Microstation details and specifications along with a user-friendly design guide.

A white truck towing a camper crosses a metal truss bridge over a river under a partly cloudy sky.

Evaluation of Corrosion Prevention and Mitigation Approaches Used on Texas Bridges

TxDOT needed a decision tool to conduct effective steel corrosion prevention strategies for new construction and corrosion mitigation for effective maintenance for Texas bridges. In this project, TTI conducted a synthesis of worldwide field investigations of the performance of corrosion mitigation, performed field evaluations statewide to investigate the effectiveness of corrosion mitigation instrumented in the past, and performed lab tests to verify findings and to obtain a better understanding of corrosion mitigation approaches.

Allowable Limit Contraction Scour and Abutment Scour at Bridges

Scour at bridges is the leading cause of bridge failures nationwide. While TxDOT possesses guidance for the maximum allowable bridge pier scour depth, that guidance does not address maximum allowable abutment scour depth or the maximum allowable contraction scour depth. The maximum allowable abutment scour depth is related to the potential failure of the abutment, considering the abutment soil slope, the abutment deck support structure, and the embankment supporting the access roadway. Since the maximum allowable contraction scour depth is related to the potential failure of the bridge pier, all issues were studied considering available case histories, stability analyses, existing knowledge, and engineering judgement.

Rip-Rap for Scour Countermeasures

The use of rip-rap to protect against scour is very common both at the design stage and as a repair option. Making sure that the rip-rap will perform as planned will save money by avoiding sustained maintenance or replacement. TTI researchers conducted a synthesis of national research and in-use structures within the US and internationally to determine whether a filter between the rip-rap and the native soil is necessary. If such filters are needed, the TTI team developed a specification for the filter. The study also addressed the stability of slopes with rip-rap covers and specified recommendations to ensure the stability of the slope after rip-rap placement.

A photo of Houston Chronicle Reporter Dug Begley interviewing TxDOT employee Danny Perez.

Evaluations of Ways and Procedures to Reduce Construction Costs and Increase Competition

Construction cost inflation constrains construction and maintenance programs in many state highway agencies. While some cost increases may be attributed to statewide factors (energy costs), reports of large variations in cost of bid items among different districts indicate that the problem is more complex. TTI identified root causes or all major factors contributing to the rise in construction cost, assessed their possible impacts, and developed recommendations and guidelines on how to modify construction projects to reduce initial construction cost while maintaining quality.

Inspection Guidelines for Bridge Post-Tensioning and Stay Cable Systems Using NDE Methods

In this NCHRP Research Report 848, TTI outlined nondestructive examination (NDE) methods to explore different condition assessments, including corrosion, section loss, breakage, grout conditions, voids, water infiltration and tendon deterioration in the anchorage systems. The NDE methods included ground penetrating radar (GPR), infrared thermography (IRT), electrical capacitance tomography (ECT), magnetic flux leakage (MFL), magnetic main flux method (MMFM), impact echo (IE), ultrasonic tomography (UST), ultrasonic echo (USE), sonic/ultrasonic pulse velocity (S/UPV), low frequency ultrasound (LFUT), sounding, visual testing (VT) and electrochemical impedance spectroscopy (EIS).

Utilization of UHPC Bridge Superstructures in Texas: UHPC Production Guidelines and Design Recommendations with Design Examples

The use of UHPC in Texas bridges has the potential to add substantial improvements to bridge construction. This Volume III research report documents production guidelines, design guidelines, and design examples for precast, pretensioned UHPC girders. The design recommendations consider the UHPC draft specifications under consideration by the American Association of State Highway and Transportation Officials and the results of testing UHPC girder specimens. The design guidelines were supplemented with two detailed design example calculations to take advantage of UHPC to reduce the number of girder lines for a bridge span and to apply the potential of UHPC to increase the span length of highway bridge structures in Texas.

The Team

our Leaders