Experimental Study On Seismic Behavior And The Optimization Designing About The Steel Frame-Bent Structure Of The Large-Scale Thermal Power Plant

The destructions of the electric power plant under the earthquake will directlyresult in huge economic losses, lead to many secondary disasters, and also can makerescue difficulty after the earthquake. Considering the special technology, electric powerplants’ arrangements are often more complex than civil buildings’. There are manyweak links, lack of the balance of stiffnesses and qualities, and low of security reserves,etc. For making the structures have great seismic performances and avoid the damage ofthe building during the earthquake, it is an important practical significance to studyseismic performances of the thermal power plants with the frame-bent structure and itsoptimization design.According to test seismic performances of the horizontal steel frame-bent structureof the large-scale thermal power plant, the pseudo-dynamic and pseudo staticexperiments about the model structure with1/10scale was conducted. This papermainly covers the following aspects: the mechanism behavior of the structure underdifferent horizontal earthquake load, including hysteretic energy-dissipated capacity, thedeformed performance of the whole structures and the every layer; the changing rule ofstructural stiffness degradation, ductility of the structures, and shear distributingbetween the frame structure and the structure of the bent frame in different experimentalstages. The results shows that the structure meets the three level fortification criterionand has the seismic capacity to resist the rare earthquake of magnitude of9, but it wastoo safe to make properties of the materials play fully. It proves that the testing original structure is conservative using the design method and has great optimization space.Because the original structure is too safe, the finite element software ANSYS wasused to optimize the original structure and finite element models were built which setcomponent section size as design variables. Component section sizes of the lateralframe-bent structure without shores were optimized which sets minimum volume as asingle objective function and ones of the shores system were also optimized which setsminimum volume and the strain energy minimum as multi-objective objective function.Then, check deformation of the optimized structure under the frequent earthquake andthe rare earthquake, and that were compared with the experimental results. Thesimulated results show that the optimization design could save steel19.03%and achievesignificant effect of optimization. So the design optimizations which reduce thestructure volume ensure the lateral stiffness of the whole structure which still has a goodseismic capacity. It proves that the optimization ideas and methods are feasible in thispaper.