论文部分内容阅读
以双层球面网壳为研究对象,对其进行结构的几何优化设计和在地震荷载下的反应分析.首先分析了结构自振特性随几何参数变化的特点,研究了结构的基频随矢跨比、跨度、网格分割频数及网壳厚度变化的规律,然后采用N ewm ark积分法对其在多维地震作用下的反应进行了时程响应分析.研究结果表明,在结构跨度一定时,存在一个优化的矢跨比范围,约为1/3~1/4,该范围内,结构的整体刚度存在一极大值;对矢跨比一定的结构,结构跨度的增加将显著减低结构的整体刚度,从而减低结构的自振频率;对于跨度和矢跨比一定的结构,结构的基频随结构分割频数、网壳厚度的改变变化很小.
Taking the double-layer spherical reticulated shell as the research object, the geometry optimization design of the double-layer reticulated shell and the analysis of the response under the seismic load are carried out.First, the characteristics of the natural vibration of the structure varying with the geometric parameters are analyzed, The ratio of the length of the grid to the length of the grid, the frequency of the grid segmentation and the thickness of the reticulated shell, and then the time-history response of the response under the multi-dimensional seismic action is analyzed by using N ewm ark integration method.The results show that when the span of the structure is constant, An optimized ratio of pitch to span is about 1/3 to 1/4, within which the overall stiffness of the structure has a maximum value. For the structure with a certain aspect ratio, the increase of the span of the structure will significantly reduce the overall structure Stiffness of the structure, so as to reduce the natural frequency of the structure. For the structure with certain span and span ratio, the fundamental frequency of the structure changes little with the frequency of the structure and the thickness of the reticulated shell.