A Research On Seismic Protection Performance And Strategy For The Frame Structure Turbine Generator Foundation At Power Plant

An investigation on seismic response is performed for the rigid and the spring supported frame structure turbine generator foundations at power plant based on the finite element method with an international common software in the paper. Under the action of the same seismic peak ground acceleration, the amplification for the response acceleration at the operation floor is calculated and compared for two foundations, and the seismic protection strategies of turbine generator foundation is discussed. Compared with the rigid foundation, the spring supported foundation is able to highly decrease the amplification at the operation floor basically with the lower first order of horizontal basic frequency, at the same time some additional viscous dampers can be easily added to increase damping ratio, which is also able to highly decrease the amplification. The amplification is about3.0for the rigid foundation, no matter the type of the site being of class Ⅰ, or class Ⅱ,or class Ⅲ, or class IV, and less than1.0for the spring foundation for the site from class I to class Ⅲ, and about1.3for class Ⅳ. As a result, the spring foundation can perfectly improve the seismic protection performance for the T/G machine due to decreasing the amplification.