ABSTRACT

For the tridirectional time histories for seismic analysis, current codes and standards cannot guarantee isotropy in the horizontal directions, the code formula for statistical independence between components is not rigorous, and the bounds are arbitrary. In this paper, three conditions are defined for the horizontal inputs to be isotropic. Orthogonality is proposed to replace the statistical independence for the tridirectional components. Furthermore, the importance of a proper rate of mobilization of the excitation energy of a generated time history is discussed and emphasized, and an acceptance region is proposed for practical applications.

中文翻译：

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地震设计加速度图的方向分量

摘要

对于地震分析的三向时程，现行规范和标准不能保证水平方向的各向同性，分量间统计独立性的规范公式不严谨，界限随意。在本文中，定义了水平输入各向同性的三个条件。提出了正交性来代替三向分量的统计独立性。此外，讨论并强调了生成时程的激发能量的适当动员率的重要性，并提出了实际应用的接受区域。