大跨圆拱屋盖结构的风致响应分析

大跨屋盖特征值问题的求解是结构动力响应分析中最繁琐的一个环节，而且一些对结构响应贡献较大的高阶模态容易在传统的模态叠加法中被忽略。本文以典型的大跨圆拱屋盖为例，将里兹向量直接叠加法应用于屋盖系统特征值问题计算和风致响应分析，其特点是在误差逼近的基础上自动生成一组正交的里兹向量并用于缩减系统自由度数。与传统模态叠加法算得的结果相比，里兹向量直接叠加法只用很少数目的向量就可以得到较精确的结果，而且高阶模态的贡献不会被忽略。该方法不仅大幅度地减少了机时，而且提供了动力分析的误差估计。

Analysis of Wind-Induced Response for Large-Span Dome Roofs

The solution of the eigenvalue problem for large-span roof structure is of the most costly phase of dynamic response analyses. And some specific modes that have dominant contributions to the structural response are easily overlooked because of their higher position of modal order while using the traditional modal superposition method. In this paper as an example of a typical large-span dome roof, the direct superposition method of Ritz vectors are used in the solution of the eigenvalue problem and the calculation of wind-induced response of the roofs. It is a feature that a sequence of orthogonal Ritz vectors is generated automatically based on the error minimization and employed to reduce the size of the system. Compared by the response obtained by the traditional mode superposition method, the direct superposition method of Ritz vectors yields more accurate results with fewer vectors and the contributions of higher modes are not overlooked. The proposed method not only reduces computation time significantly but also provides error estimation for the dynamic analysis.