Based On The Structural Safety Of The Vibration Frequency Control Method

Resonance severely influences the security application and duration of structure. When the resonance occurs, though the damping repressing the amplitude, the amplitude is magnified about several times or ten times and it can be found everywhere. With regard to the common building and constructional work the field eigenperiod and upper or built-in device can not be equal or approachable to the fundamental period of building .The thesis analyses parameter of stucture in order to controlling the frequency and not being equal to the frequency of environment.This paper mainly analyses the quantity and thickness of shearwall, the section of beam and column ,rider supporting height, and the angle between rider and floor, structure top mass, the center of gravity position affecting frequency, as well as frequency sensitivity due to the parameter change degree; at the same time, discussing concrete degree and structure height impaction on frequency, summing up the general laws as following:(1) Lower the center of structureLowering the center of structure markedly boost the self-frequency of structure. When two structures have similar figure, the low center of gravity has higher natural frequency.(2) Adding lateral bracesWhen the self-frequency of structure can't meet demand, adding lateral braces boost the whole stiffness of structure. The two factors :angle between ground and lateral braces and height of pivot point affect the stiffness of the whole structure. The higher the height of pivot point is,the bigger the stiffness is ;changing the angle between lateral braces and ground is not markedly to self-frequency.(3) Augment section moment of inertiaTo frame construction, changing section of beam and column decide self-frequency.(4) Decreasing the upper massMass, especially the upper mass, mostly decides self-frequency. Curtailing the upper mass can enhances frequency. When frequency can't meet demand , please decrease the upper mass.(5) Augment thickness and quantity of shearwallAdding the thickness and quantity of shearwall enhance frequency to frame and shearwall structure .Utilizing these laws, three Doppler towers which locate in Shangqiu andZhengzhou and Zhumadian are adjusted to satisfy the frequency of radar. The aids of this paper is structural computational software :ANSYS. It is essential to test the convergence of finite element.