Sensing, Monitoring, Control and Intelligent Systems
As advances in sensing, networking and new materials have made continuous monitoring and control of structural functions a realizable goal, the idea of the intelligent or smart system, originally applied to electrical, mechanical and aerospace systems, has now extended to include civil structures.
By definition, an intelligent structure has the ability to identify its status and optimally adapt its function to stimuli. Research focuses on mainly two areas: Identification of structural behavior or properties (e.g., deformation, energy usage and damage evaluation); and control of structural response to external (e.g., wind, earthquake) or internal (e.g., acoustics, temperature variation) stimuli. Some recent catastrophic structural failures due to natural events (such as the California earthquakes, hurricanes in the Southeast and blizzards in the Northeast and Midwest) have amply demonstrated the need for rapid assessment of structural integrity after such events, and a need to control and minimize damage.
Much of the research in the United States and abroad has gone toward the development of active control systems for structures subjected to extreme external excitations with the primary objective of maintaining structural and occupant safety. With recent advances in micromachined sensors, wireless communications devices and improved imbedded computation tools, considerable attention has also been focused on the development of near-real-time damage monitoring systems. Furthermore, the development of distributed actuation systems and better sensors and microprocessors is providing the tools for achieving optimal levels of controlled structural functionality. Advancements include smart materials fabricated to incorporate embedded computing tools such as sensors and microprocessors, and new classes of structural materials that offer the opportunity to revolutionize many aspects of civil engineering construction.
High-performance materials include applications of high-performance steels, concrete or fiber-reinforced plastics for structural frames, cement-based soil-mixing for site modification, etc., as well as special protective devices such as seismic isolators and dampers, geosynthetic membranes, etc. These new materials provide important opportunities for the design of new structures and the rehabilitation of aging or damaged structures with easier, less costly and more durable construction than conventional materials.
This area of research crosses over several fields of expertise and requires that the research from these fields be integrated in a coherent manner. For example, the design of an imbedded damage monitoring or actively controlled system requires expertise in sensor technology, radio transmission and communication, advanced computational methods, nonlinear structural dynamic behavior, smart materials, and the design of modern software and hardware systems. There is a strong focus on collaborative research with Departments of Mechanical Engineering, Electrical Engineering, Computer Science, Material Science and Engineering, and Aeronautics and Astronautics.