As the director of the University of Virginia’s Resilient and Advanced Infrastructure Laboratory (RAIL), Osman Ozbulut applies smart technologies to the development of resilient and sustainable civil infrastructure systems. Ozbulut and his research group, currently five Ph.D. and four M.S students, are focused on developing innovative structural systems and design strategies to enhance the performance and safety of structures. A primary area of expertise is the application of advanced materials to disaster resistant design of structures as well as repair and retrofit of deficient and aging infrastructure.
Some of the most interesting of these materials are shape memory alloys (SMAs). Typically nickel titanium, iron or copper based metallic alloys, SMAs return to their original state under different loading configurations. They possess excellent corrosion resistance, good energy dissipation capacity, high fatigue properties and have superelastic properties that provide re-centering ability. In other words, these materials help a structure or structural member flex and recover when exposed to an extreme event, such as a hurricane, and provide superior protection and reinforcement capabilities when exposed to adverse weather conditions.
In advancing these interests, Ozbulut has collaborated on several MATS UTC research projects. Working with Devin Harris, Ph.D., associate professor at UVA, and UVA graduate students, Sherif Daghas and Muhammed Sherif, the team studied the use of superelastic SMA fibers to enhance the performance of cementitious composites. They found that SMA fibers provide some advantages over traditional fibers such as the ability to experience larger deformations, crack control, and minimize permanent damages and residual displacements. Ozbulut also investigated the use of SMA fibers in a thermoset polymer matrix to develop a polymer composite that has large failure strains and recover large deformations.
Ozbulut and Harris leveraged their mutual interests to investigate additional ways to improve the durability of materials to minimize cracking, reduce permeability and porosity, improve resistance to freeze-thaw degradation, and mitigate corrosion potential. Working with UVA graduate student, Zhangfan Jiang, the team explored the electrical properties and piezoresistive characteristics of graphene nanoplatelets (GNPs) reinforced hydraulic Portland cement composites. They found that GNP-reinforced mortar specimens exhibit good piezoresistive behavior under cyclic compressive loads. Ozbulut is continuing to study the nano-reinforced composites to improve both the conductivity and load carrying capacity of the composites.
Ozbulut is currently collaborating with Wael Zatar Ph.D., Dean of the College of Information Technology and Engineering at Marshall University (MU), and Hai Nguyen, Ph.D., research scientist in civil engineering at MU, to explore how fiber-reinforced plastic (FRP) wraps, a technology that has been around for over 20 years, might offer a fresh approach to repairing and fortifying damaged bridges. Currently used primarily for specialized applications, FRP wraps hold the promise of extending the service life of corrosion-deteriorated concrete. In cleaning and repairing the damaged areas, then applying the optimal number of FRP sheets in the optimal number of directions, the life of the structure could be saved for many more years. However, cost/benefit analyses and assessment criteria are needed before State DOTs widely adopt the approach.
The team is undertaking a non-destructive evaluation approach for projects in West Virginia, a state already using FRP for infrastructure repair. Initially, they will use a variety of damage and inventory parameters to develop a prioritized classification process to help practitioners identify possible candidate structures. Ultimately, they plan to deliver an FRP reference report for bridge inspections and maintenance programs as well as recommendations for field implementations and classroom education initiatives.
In 2016, Ozbulut received an International Young Scientist Fellowship from the National Natural Science Foundation of China (NSCF). Working with researchers at the Chang’an University, Xi’an, China, he is once again studying GNPs to develop cement sensors that can be embedded in concrete structures. He hopes to show that cement sensors with intrinsic strain- and damage-sensing capabilities can be a more practical and sustainable alternative to monitor the health of concrete structures.
“The capabilities of these advanced alloys and composites really represent the future of high-performance materials,” stated Ozbulut. “We’re showing that they are durable, adaptable and reliable, representing a real step forward in our abilities to improve the health of existing structures and create better ways for new construction projects to be more sustainable.”
Ozbulut is an assistant professor in the department of civil and environmental engineering at the University of Virginia. He earned M.S. and Ph.D. degrees in civil engineering from Texas A&M University and was a post-doctoral research associate with the Texas Transportation Institute.
Ozbulut may be contacted at email@example.com.
Reports and papers referenced in this article include:
- Structural enhancements of cementitious composites (MATS UTC Final Report)
- SMA-fiber reinforced polymer composites (Materials & Design)
- SMA-fiber reinforced cementitious composites (Cement and Concrete Research)
- Electrical properties and piezoresistive characteristics of graphene nanoplatelets (MATS UTC Final Report)
- Fiber reinforced plastic FRP wraps (MATS UTC Project Overview)