Civil structures such as sports stadiums, arenas and auditoriums are usually built for venues where hundreds or even thousands of people assemble. A possible collapse of roof dome of this type of structure may risk many lives. This research focuses on an automatic structural health monitoring system for large domes that can provide early warning of structural problems from instability or damage to structural members resulting in collapse. Early warning can facilitate decision-making on repair or demolition, leading to worry-free structures for both the general public and the owners. The system has potential use to protect historical structures (e.g., cathedrals), to verify the appropriateness of repairs of dome structures, and to evaluate the health condition of these structures after an earthquake or a strong wind event.
The objective of this research is to develop innovative yet practical approaches to detect damage and instability in space structures under operational or multi-hazard environments. This research objective will be achieved through three research tasks: 1) develop an approach to detect damage based on the status of fractal patterns of structural member configuration using fractal geometry; 2) develop different approaches to detect instabilities, including individual members buckling, nodal snap-through instability or dynamic instability; and 3) integrate these approaches through a wireless sensor network with multi-metric measurements (tilt angles, strains and/or accelerations) to form a structural health monitoring system. The goal is to achieve automatic early-warning of damage, instability and potential collapse. Although projected approaches work on the shape/pattern changes of the structure, no direct displacement measurements will be required. The shape/pattern changes are strategically reflected in tilt angles, strains and accelerations, which can be measured easily. These approaches also do not require baseline response data. The developed structural health monitoring system can detect instability and can work under multi-hazard environments.
