Optimal placement and innovative design of energy dissipation systems for civil engineering structures

In this dissertation, innovative methods of optimal placement and design of capacities of passive energy dissipation systems have been proposed. For large civil engineering, e.g., a tall building, the determination of optimal locations of dampers has been investigated through integer heuristic programming approach. In this approach, the integral optimization of damper placement problem is carried out through heuristic (intelligent) search methods. Three such methods namely, sequential search, worst-out-best-in (WOBI) search and exhaustive single point substitution (ESPS) search, have been identified. These search methods have been used for determining optimal locations of dampers by optimizing various objective functions, e.g., average dissipated energy by passive dampers, damping ratio of the fundamental mode, {dollar}Hsb2{dollar} cost for interstory drifts, maximum of peak of interstory drifts, etc. The application of proposed search methods has been investigated for four different types of building structures. Results of numerical simulations demonstrate that the proposed approach is very effective in improving the performance of passive energy dissipation system through placement at optimal locations.; Various advanced active control theories have been developed to shape vibration and dynamics of structures in a desirable form. We have investigated the applications of some of the advanced active control theories for the design of passive energy dissipation systems. For actual building structures, the stiffness of story units decreases from bottom to top story unit. Hence, it may be desirable to design capacities of dampers such that damping coefficients of dampers decrease with decrease in stiffness of story units. This task is easily achieved through the application of four proposed methods for innovative design of dampers. The performance characteristics of these methods have been investigated and it has been found that these methods economize the installation of dampers by reducing the required capacities of dampers without any degradation in performance.