Research On The Dampers Optimization Of Passive Collision Of Retractable Roof Structures Based On Genetic Algorithm

As a perfect combination of Mechanical Engineering and Structural Engineering, retractable roof will be largely extended and applied widely in large public building. At present, the research on retractable roof focus mainly on static analysis, but further research should be centered on mechanism of collision and reactive safety technology of anti-collision, because the retractable roof movement causes structure collision, and the collision causes structural response which is stronger than seismic response and wind-induced response.Genetic Algorithm has been widely used in structural optimal design. In this paper the dampers optimization is solved with Genetic Algorithm, and programmed with APDL; a suitable fitness function is chosen which takes two factors that largest energy dissipation and economy into consideration; the condition that retractable roof collides with fixed roof is analyzed and calculated; optimal layout and amount of dampers are got .At the same time, through parametric analysis the effects on optimal results are got according to different damping coefficient, different collision velocity and different rise span ratios.Research indicates that ,when retractable roof collides with fixed roof at a certain speed ,dampers arrange in the top chord and flank rod positions ,while bottom chord positions arrange almost no damper;And it is useful for energy dissipation that dampers arrange around roof support or mid-span. On the whole, the percentage of energy dissipation increases with the number of dampers; on the contrary, the average energy dissipation decreases with the number of dampers increasing. Then, energy dissipation and energy dissipation efficiency for each damper declines. When retractable roof collides with fixed roof, damping coefficient has nothing to with the optimal layout and amount of dampers; collision velocity and rise span ratio has the same effects on the dampers optimization, that the dampers optimization is concerned with collision velocity when the amount of dampers is small, in contrast, collision velocity has little effects on the dampers optimization when the amount of dampers is big.