Investigation On Seismic Response Of Liquid Storage Tanks On Seasonally Frozen Ground

Our country have the far-flung frozen earth territory, it is the third in the four countries that have the broadest frozen earth area. There are 5.14 million sq.km seasonally frozen ground in our country, it is about 54% of the country. The soil of the frozen ground transit from un-frost state to frost state or on the reverse cycle, property of the soil will occur a great transformation and the strength target will increase or decrease dramatically. The same place of Dedu region in Heilongjiang province happened twice earthquakes over 5 grade in the spring and summer in 1986 ,the seismic damages were polarity. The thickness of the frost-thaw layer in the northeast, northchina and the most area in the northwest exceed 1.5m, the intensity exceed 7 degree. Trough the investigation of freeze damages mechanism and dynamic characteristics, the seismic damages can be decreased to the lowest degree and the theory gist can be provided for improving the earthquake resist character of the tanks. So the investigation on seismic response of liquid storage tanks on seasonally frozen ground has a great significance in theory and engineering practice.So this paper takes the tanks on seasonally frozen ground as study object to complete the investigations as follow:Chapter 1:To ascertain earthquake parameters of the seasonally frozen ground and the characteristic ofthese parameters and sum up the changing character of the Poisson ratio , shear modulus and dampratio that change from un-frost state to frost state.Chapter 2:To ascertain the predigest mechanics model and math model that same with the engineeringpractice .ascertain the movement and the control equation and give the calculating formula of shearingforce and bending moment on tanks' base.Chapter 3:To study the seismic response of the tanks on 8 seasonally frozen grounds and compare theseismic response of the tanks on the un-frozen ground with the seismic response of the tanks on thefrozen ground., then prove that the existence of the seasonally frozen ground affect the seismicresponse characteristic of the tanks.Chapter 4: To study the theory analysis method of the seismic response of the tanks on the seasonallyfrozen ground and compare the results of this method with the results of numerical analysis of chapter3 to approve the validity of this method.Through the study, we can get the results and practical values as follow:1. Provide the theory analysis basis for earthquake resist design of the tanks on the seasonally frozen ground;2. Establish the science theory method for the engineering practical computation;...