Experimental Study On Seismic Performance Of A Foundation For 1000 MW Turbo Generator Set Under Multi-conditions

Buildings for electric power production are related to lifeline engineering,which play an important role in Disaster Prevention and Mitigation Engineering.Foundation for turbo generator set,as a kind of special structures,is a major part of electric power production buildings.The foundation for turbo generator set whose unit capacity is 300 MW and above should be divided into key fortification class buildings.Because turbo generator set.is a large,sophisticated and revolving dynamic machine,the foundation,which is used for bearing the set,is required to have strict limit values of dynamic characteristics,usually performing a special research.At present in China,abundant research achievements for the foundation have been acquired through in situ tests and physical model tests.However,there is definite otherness in structural design of this kind of foundations,because of deferent design and production standards for turbo generator set manufacturers.Therefore,it is still necessary to carry out a comprehensive study on the foundation with specific structure distribution.Object studied in this paper is a kind of reinforced concrete(RC)frame-type foundation,which is designed to bear 2×1000 MW ultra-supercritical turbo generator set in a thermal power plant.To get dynamic characteristics and seismic performance of the foundation,method of model test is adopted.First,with the foundation as prototype,a 1/10-scaled RC model is designed and constructed,based on principle of similitude.Then five kinds of researches are performed on the model,including:(a)modal test by using three-dimensional exciting method through vibration exciters;(b)dynamic response prediction of forced vibration based on vibration theory;(c)dynamic stiffness test on bearing beam by using hammering method;(d)pseudo-dynamic test by using a-method;(e)pseudo-static test by using deformation control mode.Finally,based on principle of similitude,get converted values for the prototype from results of model above.Study in this paper shows that the foundation basically has qualified dynamic characteristics and seismic performance,but increased vibration control of middle floor is still required.In addition,this paper proposes that design institute can appropriately reduce the longitudinal design bearing capacity of frame column at super high turbocharged area and high turbocharged area,under the premise of satisfying the requirements of dynamic characteristics.