Abstract
A method for global simultaneous optimization of oil, hysteretic and inertial dampers is proposed for building structures using a real-valued genetic algorithm and local search. Oil dampers has the property that they can reduce both displacement and acceleration without significant change of natural frequencies and hysteretic dampers possess the characteristic that they can absorb energy efficiently and reduce displacement effectively in compensation for the increase of acceleration. On the other hand, inertial dampers can change (prolong) the natural periods with negative stiffness and reduce the effective input and the maximum acceleration in compensation for the increase of deformation. By using the proposed simultaneous optimization method, structural designers can select the best choice of these three dampers from the viewpoints of cost and performance indices (displacement, acceleration). For attaining the global optimal solution which cannot be attained by the conventional sensitivity-based approach, a method including a real-valued genetic algorithm and local search is devised. In the first stage, a real-valued genetic algorithm is used for searching an approximate global optimal solution. Then a local search procedure is activated for enhancing the optimal character of the solutions by reducing the total quantity of three types of dampers. It is demonstrated that a better design from the viewpoint of global optimality can be obtained by the proposed method and the preference of damper selection strongly depends on the design target (displacement, acceleration). Finally, a multi-objective optimization for the minimum deformation and acceleration is investigated.
Highlights
Passive dampers are becoming innovative and inevitable technologies for reducing the vibration of structures and infrastructure against natural disturbances, e.g. earthquakes, strong winds
A local search is conducted for high accuracy after the search by the real-valued genetic algorithm (GA)
It seems that the proposed approach including the real-valued GA prevents from attaining a local minimum which is often reached by the sensitivity-based approach
Summary
Passive dampers are becoming innovative and inevitable technologies for reducing the vibration of structures and infrastructure against natural disturbances, e.g. earthquakes, strong winds. Large-scale structures, e.g. high-rise buildings, cannot be designed in earthquakeprone or hurricane (typhoon)-prone countries without passive dampers. The problem of damper optimization has been investigated extensively since the milestone research due to Zhang and Soong (1992) where a sensitivity-based approach (or sequential allocation approach) was developed by including a simple sequential algorithm of damper allocation. The sensitivity-based approach was advanced afterward for elastic building structures with linear oil dampers by incorporating the mathematical and mechanics-based backgrounds (Takewaki 1997; Takewaki et al, 1999). Adachi et al (2013) extended this approach to the optimal allocation of nonlinear oil dampers
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
