3 message from center director

4 national transportation center of excellenceThe University of Connecticut was among seven institutions designated as a National Transportation Security Center of Excellence (NTSCOE) in the Improving America’s Security Act of 2007. 5 geomaterials & geomechanics Chemically stabilized soil can withstand heavy loads, such as those required for the levee systems, or intermittent uses such as high speed rail. Another facet involves prediction of soil and geo-structural responses to various normal and destructive loads.

7 structural monitoring & controlDevelopment of vibration reduction techniques and structural health monitoring to advance bridge safety. State-of-the-art structural control techniques will be able to diagnose problems and redirect the energy and vibrations in a way that predicts the severity of the damage. 9 advanced materials for infrastructure protection Strong, versatile metal structural materials that can successfully mitigate both explosive force and fire damage. A novel twist involves exploiting blast waves as a means to transform the materials into new materials capable of withstanding fire. 10 ultra-high performance concrete Revolutionary ultra-high performance concretes (UHPC) that provide superior strength, ductility, blast and fire resistance, as well as durability and resistance to environmental degradation relative to conventional concretes. 11 transportation network analysis Identification of vulnerable pieces of the transportation network, such as roads, bridges and fuel pipelines, through the use of game theory.

12 crti faculty

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The Center for Resilient Transportation Infrastructure (CRTI) was founded at the University of Connecticut in August 2008 as part of the Department of Homeland Security National Transportation Security Center of Excellence (NTSCOE). The mission of the NTSCOE is to develop new technologies to protect the nation’s multi-modal transportation infrastructure and to develop education and training programs for transportation security geared toward transportation employees and professionals. The goal of CRTI is to develop novel technologies to enable the next generation of sustainable and resilient transportation infrastructure. CRTI conducts basic and applied research that addresses infrastructure protection and risk management for complex transportation systems—comprising interconnected bridges, highways, tunnels, rail, geo-structures and other support structures—at both the individual component and overall network levels. CRTI’s focus is on the development of new materials, monitoring and control strategies and modeling and simulation capabilities to enhance infrastructure protection and emergency response and recovery strategies.

www.ntscoe.uconn.edu/crti

Welcome to the fall 2010 newsletter of the Center for Resilient Transportation Infrastructure (CRTI). I am pleased to have this opportunity to showcase the outstanding research being performed at the University of Connecticut in the area of transportation infrastructure protection and security. CRTI is one of seven institutions comprising the National Transportation Security Center of Excellence (NTSCOE) founded by the Department of Homeland Security in 2008. The mission of the NTSCOE is to support our nation’s homeland security enterprise through premier research, education, and training initiatives. In addition, the NTSCOE has set out to develop new technologies, effective tools and advanced methodologies to protect and increase the resilience of the nation’s multi-modal transportation infrastructure.

Within this broad mission, the focus of CRTI is to conduct basic and applied research that leads to the development of new technologies to protect physical infrastructure and new strategies for responding to and recovering from extreme events. Our research encompasses a multi-level strategy for transportation infrastructure from the development of new materials, advancing to monitoring and modeling at the structural level, and finally, leading to analysis and simulation of large-scale transportation networks. This newsletter highlights our achievements in these areas over the past year. In addition to our basic research mission, we continually welcome the opportunity to strengthen the impact of our work through strategic collaboration and partnering with state and federal agencies and the private sector. Please contact me if you are interested in learning more about CRTI and opportunities for collaboration.

Sincerely,

Michael accorsiCenter Director

Message from the Center Director

MICHAEl ACCORSI, PH.D.Director accorsi@engr.uconn.edu 860.486.5642

AMY SMITHAdministrative Services Specialistamys@engr.uconn.edu860.486.8026 KATE KURTINWriter

CHRISTOPHER laROSA Graphic Designer

Center for Resilient Transportation InfrastructureUniversity of ConnecticutSchool of Engineering261 Glenbrook Road, Unit 2037Storrs, CT 06269-2037www.ntscoe.uconn.edu/crti 3

The University of Connecticut was among seven institutions designated as a National Transportation Security Center of Excellence (NTSCOE) in the Improving America’s Security Act of 2007. The Centers of Excellence are intended to conduct research and educational activities and to develop or provide professional security training to transportation professionals and transit employees. UConn is the research lead for the center while Tougaloo College and Texas Southern University oversee education and training programs, and petrochemical transportation security, respectively. The network also includes Rutgers University, Long Island Univer-sity, the University of Arkansas, and San Jose State University. The joint efforts of these seven national institutions are focused on transportation infrastructure and networks, and transportation sys-tems and operations. UConn’s research activities center on the development of novel materials, sensor capabilities, and computer models that can be applied to protect America’s infrastructure. After the events of 9/11, the U.S government formed the Department of Homeland Security (DHS) as a means “to secure the nation from the many threats we face” (www.dhs.gov). “After 9/11, people were looking at infrastructure development and saying that ‘we would need to build everything like fortresses,’” said Michael Accorsi, Director of UConn’s Center for Resilient Transportation Infrastructure. “You had people looking at the Twin Towers collapsing and wondering how we are going to protect all our buildings and bridges,” he finished. Living in fortresses is not a feasible option, leaving the question: ‘How do we build security into infrastructure so that our lifestyle is still enjoyable?’ With this aim as their primary objective, DHS chiefly commissions research that is concerned with managing risk and developing resilient infrastructure.

“DHS has a broad mission, but if you look at it scientifically, the question of how to build security into the engineer-ing process is extremely interesting,” Dr. Accorsi said. Structural design comes very naturally to engineers, but security is typically an afterthought, he noted. For that reason, NTSCOE is focused on resilient infrastructure. “There are many critical infrastructure components that have high risk,” Dr. Accorsi explained. “Due to this, it first requires increased protection against extreme events. Second, if there is a disaster, you must respond quickly and effectively. The third challenge involves recovery follow-ing infrastructure damage,” he finished. Following the 9/11 attacks the need to return to a semblance of ‘normalcy’ was a major challenge. It is for this reason that an emerging concept in the field is “minimizing consequences.” “Overall, with resilient infrastructure you are trying to minimize the loss of operational capacity over time. September 11th was a tragedy, but the impact continued for weeks after, with the economic loss during the recovery period.” In order to achieve these goals, UConn works in the area of infrastruc-ture protection by developing materials capable of withstanding extreme loads, such as blasts, fires, or earthquakes. Additionally, UConn researchers are developing sensors that are able to communicate what is happening inside of the structure. “If the structure can tell you what is going on, it allows you to act more effectively,” Dr. Accorsi said. The third research area that UConn researchers are focused on is modeling, computer simulation and transportation network simulation. This modeling allows researchers to realistically and reliably predict how a structure will respond to any number of loads. Additionally, network simulation allows researchers to predict what would happen to a network if one arm was disturbed.

national transportation center of excellence

The Next Generation of Resilient Transportation Infrastructure

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The scale of the center’s activities is large. During its second year, the center involved 14 faculty members from four engineering departments and 14 gradu-ate students and eight undergraduates. As director, Dr. Accorsi has several roles. The first is to keep a close partnership with DHS to make sure that UConn researchers know the department’s needs, address them through research, and then deliver. Second, Dr. Accorsi feels very strongly about his role in engaging UConn’s faculty in DHS’s mission. “Our work with DHS is a long-term effort,” Dr. Accorsi explained. “We would like the faculty to be able to leverage funding from other sources. Ideally, our faculty could take the idea that was generated by a DHS project and write a success-ful NSF proposal.” Dr. Accorsi’s third responsibility is to serve as a facilitator between UConn’s faculty and other agencies. “I try to arrange meetings with faculty and other agencies that work with DHS. This is all in an attempt to transi-

tion our research out of the lab and to make an impact,” he explained. One example of this is a new project with Drs. Christenson and Tang that involves scaled model testing at the Army Corps of Engineers. Dr. Accorsi works tirelessly to grow the center at UConn with the goal to make it sustainable. “I put the icing on the cake,” Dr. Accorsi said. “Sometimes I also work on the cake itself,” he said, referring to his own proj-ect on ultra-high performance concrete. The NTSCOE is initially a four-year engagement and UConn is currently finishing its second year. “The upcoming year is critical,” said Dr. Accorsi. “We have done really well with basic research; it was really strong and relevant, but this year we need to transition and increase our outreach,” Dr. Accorsi stated. “It is a tremendous pleasure to work with the dedicated personnel at DHS and the talented faculty and students at UConn on this important mission.”

aim: Chemically stabilized soil can withstand heavy loads,

such as those required for the levee systems, or

intermittent uses such as high speed rail. Another facet

involves prediction of soil and geo-structural responses

to various normal and destructive loads.

geomaterials & geomechanics

Strengthening the Foundations of Our InfrastructureIt was a perfect union when the Department of Homeland Security (DHS) designated the UConn School of Engineering a National Transporta-tion Security Center of Excellence (NTSCOE). Civil & Environmental Engineering (CEE) faculty members Maria Chrysochoou, Dipanjan Basu, and Amvrossios Bagtzoglou had already begun to lay the foundation for research high on the priority list for DHS. The professors make up UConn’s geotechni-cal team with specialties in foundation materials, chemical soil stabilization and soil modeling. Meanwhile, DHS was interested in understanding and modeling soil responses to dynamic processes, levee systems, and explosions. The researchers took a two-pronged approach to the DHS challenge. Dr. Chrysochoou is looking at the mechanical responses different soil types

have to heavy loads or intermittent use (think of a high speed rai—sporadic bursts of speed and stops) and how to improve that response by substituting waste materials for expensive cement. This portion of the study also focuses on ways to use the newly constructed durable soil to build levee systems capable of sustaining natural attacks, such as those endured in hurricane Katrina. The second research prong, led by Dr. Basu, aims at developing a research framework that can accurately predict the response of soil and geo-structures (e.g., building and bridge foundations, tunnels, or embankments) to a variety of loads, such as high speed rail, blasts, or missile penetration. The current focus is on developing models that capture soil responses to blasts and aim to predict how the soil will react in an explosion.

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Photo by Rene Schwietzke

The general objective of the geotech-nical team’s research is to understand soils as foundation materials. “When you build any structure, say a bridge or levee, it rests on soil. Therefore, understanding how much load the soil can take, and how it responds to the load that has been placed on it, is the general objective,” Dr. Chrysochoou says. She notes that the project with DHS involves greater complexity, “If the natural soil lacks proper characteristics needed, then you have to do something to make it better. In general, that is what we call ground improvement,” Dr. Chrysochoou explains. To achieve these goals, one of the common industry practices is to add cement to the soil as a chemical addi-tive to stabilize it. The problem with this method is its high cost. “What the project is looking at is substituting waste products for cement to do the same job,” Dr. Chrysochoou explains. Examples include the waste produced from coal or steel manufacturing, “This process has been established in roadway construc-tion, but we have no good understanding of the dynamic properties of stabilized soil,” she says. In the course of the project, Dr. Chrysochoou and her team will look at how the chemically stabilized

waste-soil will respond to a high speed rail. A companion question is whether this waste-stabilized soil can be used to build levee systems. Due to the wide-spread failure of flood protection systems during hurricane Katrina, large amounts of materials are needed to facilitate re-pair. The final step involves the selection of locally-available industrial byproducts in lieu of commercial products to repair the levees. Meanwhile, Dr. Basu and his team are developing soil constitutive models as a predictive tool. Soil is a heterogeneous system, the researchers explain, and the individual components in soil—air, water and soil particles—display different properties under different loading condi-tions, making the overall soil response very difficult to predict. Because of this, a model that can predict soil response to a variety of loading using the most general principles of physics is extremely valuable to the future of site evaluations. Dr. Basu is interested particularly in modeling blasts, an area of deep concern for the DHS. Among the questions Dr. Basu is trying to answer are, if there is an explosion: “What would the dam-age be?” “How big a crater would be created?” And “How far down the road

will structures be affected?” Specialized experiments are currently underway on military bases to test the accuracy of Dr. Basu’s models in predicting those outcomes. At this stage, both research projects are off to great starts. First, Dr. Chryso-choou and her team have obtained pure soil and started testing a few waste chemicals in comparison to cement to see how they compete against the indus-try standard. In addition, suites of tests have been completed to understand the properties of the pure soil, such as how it responds to static loads as a function of water presence, and what the change in chemical composition is with time. The next steps are to look at its dynamic and hydraulic properties. To date, Dr. Basu and his team have developed a constitutive model that predicts fast and intense loading events.The model can predict both static and dynamic loads for sandy and clayey soils. There are many complexities involved, as already mentioned, and improvements are on the way to make the model the most general predictive model available to date.

When you build any structure, say a bridge or levee, it rests on soil. Therefore, understanding how much load the soil can take, and how it responds to the load that has been placed on it, is the general objective.

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Richard Christenson (Civil & Environ-mental Engineering) and Jiong Tang (Mechanical Engineering), both special-ists in structural dynamics, control and monitoring, are joining forces on a proj-ect that takes advantage of their differing disciplines. Dr. Christenson’s primary area of expertise is the overall behavior of civil structures subjected to dynamic loading. Meanwhile, Dr. Tang focuses on the behavior of mechanical systems and the local behavior of such systems. Sharing a common interest in reducing damaging vibrations and identifying the structural health through vibration measurements brought the two researchers together. Specifically, Dr. Tang introduced Dr. Christenson to the piezo electric sensors used in mechanical engineering to transport information about global, as well as local, structural damage. Meanwhile, Dr. Christenson is sharing his knowledge of applying such technologies to large-scale civil structures. “This project came together through the idea that bridge health monitor-ing and structural control in a broader sense can be leveraged to better improve the performance of each component,” Dr. Christenson explains. “Whereas traditionally they have been looked at separately, our intent is to study them as one unit in a synergistic sense,” he finished. This interdisciplinary approach

rests on the old saying, ‘the whole is greater than the sum of its parts.’ By looking at structural con-

trol and health monitoring individually, it is possible to get good performance; however, if you look at the whole, the parts not only help themselves, but also one another. On a technical level, structural control asks: ‘How do we apply exter-nal forces to the structure to reduce the vibrations and response of the structure to some excitation?’ Continuing on,

structural health monitoring poses the question: ‘How can you use vibration response of the structure to identify the structural health?’ Piezo electric sensors can be used in both structural control and health monitoring. In practice, if the structural health monitoring component identifies damage on a certain element, structural control may be able to react accordingly and help protect, or favor, that element. An additional benefit to this fusion of structural control and health moni-toring, Dr. Christenson explains, is the unknown excitation factor. Alone, health monitoring can look only at the output effect of heavy blast loadings on a bridge; it does not convey the size or weight of the blast. Including structural control provides the ability to excite the structure offering known input. “Bridge structural health monitoring is often put into terms of human health,” Dr. Christenson clari-fies. “If you are running along and you sprain your ankle, one thing you can do to diagnose the injury would be to put some weight on your ankle or try and run a little bit to see how bad it is. In a similar way, the structural control moni-tor could sense that something is wrong and redirect the energy and vibrations to query it to decide if you really have damage, and how bad the damage is.” In application, it is the piezo electric sensor that can excite the structure at a high frequency, allowing it to precisely diagnose the damage. This project began really as a discus-sion between the researchers long before pen was put to paper. The conversa-tion was transformed into action by the School of Engineering’s selection as a Department of Homeland Security (DHS) National Transportation Secu-rity Center of Excellence (NTSCOE). Bridge structural integrity is an area of keen interest for DHS, so it provided a perfect opportunity for Drs. Christenson and Tang. “We had talked about doing a project on this and when NTSCOE came along it was our chance to

aim: Development of vibration reduction techniques

and structural health monitoring to advance bridge

safety. State-of-the-art structural control techniques

will be able to diagnose problems and redirect the energy and vibrations in a

way that predicts the severity of the damage.

structural monitoring & control

Bridging Disciplines

This project came together through the idea that bridge health monitoring and structural control in a broader sense can be leveraged to better improve the performance of each component

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actually look at this, so we started down that road,” says Dr. Christenson. Specifically, DHS is focused on so-called multi-hazards. “If you have this control and monitoring system, you can design the system to be multi-hazard —to look for damage due to traffic or seismic events like earthquakes or blasts,” Dr. Christenson explains. Continuing with the example of an earthquake, Dr. Christenson illustrates, “First off, during the earthquake you can control the responses—try to reduce the damage right then. Following the earthquake, you could determine whether there was damage to the structure or not.” This is of vital importance to DHS. It would indicate if the structure was stable enough to withstand the weight of the vehicles currently on the structure. In addition, it would accurately show if the structure was strong enough for first responders to cross over, or if they needed to find an alternate route.

A second point of interest for DHS is how to build structures to withstand heavy blast loads from terrorist attacks or natural disasters. The control and moni-toring system being developed by Drs. Christenson and Tang would allow the greatest ability to assess damage to the structure. “During a blast it very difficult to get an estimate for structural control because it is immediate, but immediately after the blast you can use this synergistic control and monitoring to identify dam-age, and if there is damage, try to redis-tribute the load to make the structure as safe as possible,” says Dr. Christenson. With these structural monitoring and control goals in mind, the general framework the researchers are looking at is multi-hazard protection. At the current stage in their research, a 12-foot high-way bridge model has been assembled, complete with piezo electric sensors. The researchers intend to start proof of concept demonstrations on the model in the upcoming months.

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In 2002, as a response to the September 11 terrorist attacks, President Bush announced the establishment of the Department of Homeland Security (DHS) to coordinate “homeland security” efforts. The mission of the office and collaborative partners is to “prevent terrorist attacks within the United States; reduce the vulnerability of the United States to terrorism; minimize the damage, and assist in the recovery from terrorist attacks that do occur within the United States” (www.dhs.gov). Compelling these efforts was the catastrophic failure of the Twin Towers in response to the explosive force of the striking airplanes and the subsequent fire that resulted from the attack. Until 9/11, structural studies had focused on the development of buildings capable of withstanding either blast loading or exposure to fire; however, structural materials that can successfully mitigate both threats have yet to be developed. Responding to this need, Rainer Hebert, Bryan Huey, and George Rossetti—all Chemical, Materials & Biomolecular Engineering (CBME) professors from UConn; Jeong-Ho Kim, of UConn’s Civil & Environmental Engineering (CEE) department; Richard Riman (Rutgers University) and Arun Shukla (University of Rhode Island) put together a proposal to develop new material concepts for combined blast and fire resistance. “What we have in mind is to essentially take advantage of the blast waves,” Dr. Hebert explained. “Instead of looking at the blast waves as detrimental, we propose to see them as transforming the materials that we have developed into new materials that can then withstand fire.” The proposal was accepted in early 2010 and the team is initiating work on this exciting project. With the official kick-off in July 2010, this is still a very young project, but both the research team and their contacts in DHS are clear on their objectives. “The goal of the research is primarily to develop long-range concepts

more than quick solutions that can be commercialized in the near term,” Dr. Hebert observed. Working on these solutions, Dr. Hebert’s primary task is synthesis—how to make the materials to be used, and specifically, how to combine and select composite materials. Drs. Huey and Rossetti are collaborating on the characteristics side and on micro-struc-tures. Dr. Kim will perform computer modeling of the new materials at the microstructure level which will provide the team with a unprecedented under-standing of the material behavior. At Rutgers, meanwhile, Dr. Riman is in charge of developing advanced oxide materials and on attaching them to the metal. Dr. Shukla, a blast expert, will expose the sample materials to blast loadings in his specialized laboratory at the University of Rhode Island. The team is looking at purely metallic materials. Other research has used poly-meric, elastomeric, or textile materials but none can protect against the high fire temperatures as well as metal. “Most polymers cannot survive 800-900 degrees Celsius, which is a very realistic tempera-ture,” Dr. Hebert explained. As of now, there is no designated industry standard for this level of protective materials; the closest is a composite material. “Protect-ing against blast and fire is certainly the novelty. There is a community that looks at blasts, and a community that looks at fire, and they don’t necessarily care about each other’s research. The combination is novel,” Dr. Hebert said. These researchers are not the first to attempt to create a safer building material, and Dr. Hebert explained that most of the materials research on blast resistance is restricted to national labs and the private sector and therefore not widely disseminated among the public. The team remains undaunted, thanks to the varied and high level of expertise among its members who are confident they will be able to bring something new to the table in the next two years.

aim: Strong, versatile metal structural materials that can

successfully mitigate both explosive force and fire damage. A novel twist

involves exploiting blast waves as a means to

transform the materials into new materials capable of

withstanding fire.

advanced materials for infrastructure protection

New Materials for Protecting Our Infrastructure

9

aim: Revolutionary ultra-high performance concretes (UHPC) that provide superior strength,

ductility, blast and fire resistance, as well as

durability and resistance to environmental

degradation relative to conventional concretes.

ultra-high performance concrete

Building Blocks for American Infrastructure

As a National Transportation Secu-rity Center of Excellence (NTSCOE), UConn’s School of Engineering engages in a range of research projects centered on securing our nation’s transportation infrastructure. NTSCOE was created by the Department of Homeland Security (DHS) in an effort to fund research and training on transportation security issues. With expertise in laboratory characteriza-tion of infrastructure materials, model-ing and construction, Adam Zofka and Michael Accorsi (Civil & Environmen-tal Engineering) and James Mahoney, Executive Director of the Connecticut Transportation Institute, have teamed up to study a material that is one of the primary building blocks of American infrastructure—concrete. “There has been a lot of work done recently that is completely changing the chemistry of concrete to make it radically different, which will have a big impact on structures,” Dr. Accorsi says. The focus of this research is on char-acterization of ultra-high performance concretes (UHPC) and the development of predictive tools to enable the design of next generation transportation infrastruc-

ture. This work is prerequisite and complementary to other integra-tive technolo-

gies aimed at protecting our nation’s infrastructure. “Ultra-high performance concretes are a revolutionary class of cementitious materials that provide superior strength, ductility, blast and fire resistance, as well as durability and resistance to environmental degradation as compared to conventional concretes,” explains Dr. Zofka. UHPC has been completely redesigned at the micro-struc-tural level. “Instead of using standard materials, UHPCs are very fine particles that include no coarse aggregates and are a much denser and stronger concrete,” explains Dr. Accorsi.

To date, the use of UHPC in structures has been limited, and basic research is needed to accelerate its widespread usage. Because of this, there are many questions about its perfor-mance. One specific question posed by DHS is how this new UHPC will stand up to extreme temperatures, such as may occur with an explosion or a fire. Because the microstructure of UHPC is so dense, when you heat it up the moisture cannot escape, allowing steam to build up and leading to potential disintegration and eventually structural failure. An example application is a tunnel fire. Dr. Accorsi explains, “Most tunnels are built of concrete. So if a vehicle full of gasoline explodes in a tunnel, tempera-tures of 1000ºC can result.” Under those conditions, he said, any concrete would lose its bearing capacity and integrity. Knowing this, the researchers intend to conduct at-temperature mechanical testing of UHPC specimens in a 1000ºC furnace. The results of this testing will be used to advance the team’s abilities to analytically model the behavior of UHPC. Furthermore, the team will conduct laboratory tests with digital image correlation to validate the model-ing capability. All of this is in an effort to characterize the UHPC in order to be able to predict and model if and when a UHPC structure will fail. The final stage of this research will be to conduct large-scale benchmark simulations, such as building a tunnel in a computer program and to model how it will behave at different extreme temperatures. When completed, this research will change the foundation of basic transportation and construction-based infrastructure. “This pioneering work will provide the necessary foundation for accelerated usage of UHPC in next gen-eration infrastructure,” says Dr. Zofka.

There has been a lot of work done recently that is completely changing the chemistry of concrete to make it radically different, which will have a big impact on structures

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“Have you ever heard of ‘game theory’?” Nicholas Lownes (Civil & Environ-mental Engineering) asks as he starts to explain his current Department of Homeland Security (DHS) sponsored research grant with Reda Ammar, Department Head of Computer Science & Engineering, and Sanguthevar Rajasekaran, UTC Professor of Computer Science & Engineering. He is referring to the theory that attempts to mathematically capture behavior in strategic situations, in which an individual’s success in making choices depends on the choices of others. Drs. Lownes, Ammar and Rajasekaran are applying game theory to identify critical risks in our nation’s transportation networks. In 2008, UConn was named one of DHS’s National Transportation Centers of Excellence (NTSCOE) and was given the task of researching and developing new technologies that will protect the nation’s multi-modal surface transportation infrastructure. This multidisciplinary effort fit the DHS mission perfectly. “The idea of our project is to use mathematical models to help us identify pieces of the transporta-tion network, like roads, bridges, rail and even pipelines, which are more vulnerable because of the number of people that travel over them or because of a geographic location, for example,” Dr. Lownes explains. He continues, “Our system looks at the way the entire network is built to try to identify pieces that a terrorist might try to disable or destroy.” In essence, the researchers are taking DHS’ mission of protection and making it a little bit easier. “What we are trying to do is prevent such incidents from ever happening,” Dr. Lownes explains. Applying game theory, the research-ers have created a computer program that plays a game between a benevolent character, who wants to help people travel safely, and an evil character, who is trying to disrupt the network as much as possible. In this computer program,

the benevolent character and the evil character are able to make decisions based on real city maps and networks much like a game of chess. First the benevolent character makes a move based on safety; this is followed by the evil character’s response. This volley goes on until there are no moves left to make. This activity can then be graphed and an output is created detailing the most vulnerable links in the network. “From a practical standpoint, we have used this game to try to identify vulnerable links and to provide the graphic outputs to a state Department of Transportation or a transportation engineer or planner. This provides valu-able insight into the most critical points in the network that warrant monitoring or strengthening,” says Dr. Lownes. The intent of this research is to allow the recipients of this information to make better decisions in deploying secu-rity technology, whether it is sensors or improving the infrastructure by making it stronger. “This is designed as a deci-sion support tool,” clarifies Dr. Lownes. The breadth of this research requires a multidisciplinary approach. For example, Dr. Lownes’ background is in transportation network modeling; Drs. Ammar and Rajasekaran both have a computer science background and specialize in software, theory, and efficient algorithms. In terms of the project timeline, the researchers have laid the foundation for both game theory and graph theory, “the meat behind the interface,” as Dr. Lownes calls it, and are beginning to develop the software tool. “The tool itself is in development, and now we are at a point where we can start to integrate additional factors including broader network structures and some safety modeling aspects; essentially, a more robust definition of vulnerability,” says Dr. Lownes. As a final step the team will create a software tool that allows users to upload their own networks and be able to identify where they need to focus their security efforts.

aim: Identification of vulnerable pieces of

the transportation network, such as roads, bridges and fuel pipelines, through the

use of game theory.

transportation network analysis

Transportation Network Games

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Michael accorsiDirector, Center for Resilient Transportation InfrastructureProfessor, Civil & Environmental EngineeringComputational Mechanics, Finite Element Methods, Constitutive Modeling

reda aMMarProfessor, Computer Science & Engineering Software Performance Engineering, Parallel and Distributed Computing, Real-Time Systems

aMvrossios BagtzoglouProfessor, Civil & Environmental EngineeringWater Resources and Hydrology, Geoenvironmental Engineering, Numerical Analysis, Geostatistical Simulation

dipanjan BasuAssistant Professor, Civil & Environmental EngineeringGeomechanics, Foundation Engineering, Soil-Structure Interaction, Soil/Foundation Dynamics, Ground Improvement

richard christensonAssociate Professor, Civil & Environmental EngineeringSmart Structures, Hazard Mitigation, Semiactive Stiffness and Damping Technology, Performance-Based Engineering, Structural Dynamics, Structural Control, Earthquake Engineering

Maria chrysochoouAssistant Professor, Civil & Environmental EngineeringMicro- and Nano-scale Characteriza-tion of Complex Media, Stabilization/ Solidification of Soil and Dredged Sediments, Recycling and Reuse of Industrial Waste, Geotechnical Stabilization of Expansive Soils and Waste

rainer heBertAssistant Professor, Chemical, Materials & Biomolecular EngineeringSynthesis and Microstructure Control of Amorphous and Nanostructured Alloys and Composites

Bryan hueyAssociate Professor, Chemical, Materials & Biomolecular EngineeringNovel Scanning Probe Microscopy Methods for Nanoscale Materials Property Characterization, Mapping, and Manipulation

john ivanProfessor, Civil & Environmental EngineeringStatistical Modeling of Transporta-tion systems, Highway Crash Predic-tion, Traffic Flow Characteristics and Safety, Highway Safety and land Use

jeong-ho KiMAssociate Professor, Civil & Environmental EngineeringComputational Fracture Mechanics, Functionally Graded Materials, Finite Element Methods, Structural Analysis

nicholas lownesAssistant Professor, Civil & Environmental Engineering Traffic Engineering, Traffic Simulation, Public Transportation Systems

jaMes MahoneyExecutive Director, Connecticut Transportation InstituteCharacterization and Experimental Testing of Bituminous Materials, Asphalt Pavements

sanguthevar rajaseKaranProfessor, Computer Science & Engineering Parallel Algorithms, Randomized Algorithms, Computational Geometry, Parsing Algorithms

george rossettiAssociate Professor, Chemical, Materials & Biomolecular EngineeringStructure-Processing-Property Relations in Electroceramic Materials and their Applications in Sensing, Actuation, Energy Transduction and Storage

jiong tangAssociate Professor, Mechanical EngineeringStructure and System Dynamics, Controls, Sensing and Monitoring

adaM zofKaAssistant Professor, Civil & Environmental EngineeringPavement Design, Characterization and Experimental Testing of Bituminous Materials, Reclaimed Asphalt Pavements, Theory of Viscoelasticity, Composite Materials and Micromechanics

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