Stochastic response of structures with fluid-containing appendages
Stochastic response of structures with fluid-containing appendages
复制标题
DOI：
10.1016/0022-460x(87)90405-6
复制
发表时间：
1987-12
影响因子：
4.7
通讯作者：
A. Kareem;W.-J. Sun
中科院分区：
文献类型：
--
作者：
A. Kareem;W.-J. Sun
研究了含流体附件对多自由度系统在随机环境载荷（例如地震、波浪或风）下的动态响应的影响。由连接到多自由度系统的含流体附件组成的系统的模态特性用主系统和辅助系统的单独动态特性来表达。主系统被建模为集中质量多自由度系统。晃动流体的等效集中质量模型用于表示二级系统。所有小于或等于一次系统基本固有频率的二次系统频率都包含在组合系统的动态分析中。系统的输入可以是静态或非静态白噪声或滤波白噪声矢量值激励。在这项研究中，通过利用模态脉冲响应函数并用阶梯单位脉冲函数逼近包络强度函数，计算在任何时间间隔对由非平稳滤波白噪声表示的地震的结构响应。这里提出的公式通过减少积分的重数使计算过程非常有效。使用该公式计算组合系统的响应分量的协方差矩阵。结构上任意水平处的峰值响应值可以通过遵循极值的演化分布来获得。组合系统的一个重要特征是，当辅助流体附件的晃动模式之一被调整到主系统的基本模式时，主系统的响应被抑制。使用一栋在地震激发下任意楼层都有水箱的建筑物来说明该方法。
The influence of fluid-containing appendages on the dynamic response of multi-degree-of-freedom systems subjected to stochastic environmental loads, e.g., earthquakes, waves, or winds, is investigated. The modal properties of a system comprising of a fluid-containing appendage attached to a multi-degree-of-freedom system are expressed in terms of the individual dynamic properties of the primary and secondary systems. The primary system is modeled as a lumped mass multi-degree-of-freedom system. An equivalent lumped mass model of the sloshing fluid is used to represent the secondary system. All the frequencies of the secondary system that are less than or equal to the fundamental natural frequency of the primary system are included in the dynamic analysis of the combined system. The input to the system may be a stationary or a non-stationary white or filtered white noise vector-valued excitation. In this study the structural response to an earthquake represented by a non-stationary filtered white noise is computed at any time interval by utilizing the modal impulse-response function and approximating the envelope intensity function with a staircase unit impulse function. The formulation presented here renders the computational procedure very efficient by reducing the multiplicity of the integrals. The covariance matrices of the response components of the combined system are computed by using this formulation. The peak response values at any level on the structure may be obtained by following the evolutionary distribution of the extreme values. An important feature of the combined system is that the response of the primary system is suppressed when one of the sloshing modes of the secondary fluid appendage is tuned to the fundamental mode of the primary system. A building with a water tank situated at any floor, excited by an earthquake, is used to illustrate the methodology.