Dynamic Time-History Analysis of a Steel Meteorological Tower under Seldom Occurred Earthquake Considering P-△ Effect

In virtue of the finite element software SAP2000,the dynamic character and nonlinear time-history analysis for a steel meteorological tower under seldom occurred earthquake were conducted to obtain the time history displacement,time history velocity and time history acceleration.The analysis had shown that the error to predict the natural period of high-rise tower with the empirical formula in the load code of building structures is comparatively large;and the whipping effect of the backstay on the top of the tower is very obvious and the several weaknesses occur because of the mass concentration and the stiffness mutation of the tower platforms. So some earthquake mitigations were suggested,which can be taken in the backstay and those tower platform.