A methodology for the development of design tools for direct estimation of peak inelastic response in reduced-degree-of-freedom (RDOF) isolation and energy dissipation systems is presented. The suggested procedure is an extension of an earlier method addressing purely hysteretic isolation systems. Herein, the dynamic equation of motion is first normalised to reduce the number of design parameters that significantly affect the response. The sensitivity of normalised response quantities to the amplitude of the ground motion is then investigated through extensive parametric nonlinear dynamic analyses of isolated single-degree-of-freedom (SDOF) systems with linear viscous damping using code-based target spectra. Regression analysis is subsequently employed to develop generalised design equations (GDEs) suitable for design. Further investigations are made to address nonlinear viscous damping and the effect of the transverse component of seismic action in two-degree-of freedom (2DOF) systems under bidirectional excitation, making the procedure applicable to common bridge isolation schemes. GDEs constitute an alternative to equivalent linearisation approaches commonly adopted by codes, informing the selection among alternative isolation and energy dissipations schemes without requiring iterative analysis. The approach is incorporated in the Deformation-Based Design methodology for seismically isolated bridges in a forthcoming paper.

中文翻译：

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减自由度隔离和能量耗散系统中地震响应的直接估计

介绍了一种开发设计工具的方法，用于直接估计自由度降低 (RDOF) 隔离和能量耗散系统中的峰值非弹性响应。建议的程序是针对纯滞后隔离系统的早期方法的扩展。在此，首先对动态运动方程进行归一化，以减少对响应有显着影响的设计参数的数量。然后，通过使用基于代码的目标谱对具有线性粘性阻尼的孤立单自由度 (SDOF) 系统进行广泛的参数非线性动力学分析，研究归一化响应量对地震动幅度的敏感性。随后采用回归分析来开发适用于设计的广义设计方程 (GDE)。进一步研究了在双向激励下的二自由度 (2DOF) 系统中非线性粘性阻尼和地震作用横向分量的影响，使该程序适用于常见的桥梁隔震方案。GDE 构成了代码通常采用的等效线性化方法的替代方案，告知在替代隔离和能量耗散方案之间进行选择，而无需迭代分析。在即将发表的一篇论文中，该方法被纳入了地震隔离桥梁的基于变形的设计方法中。GDE 构成了代码通常采用的等效线性化方法的替代方案，告知在替代隔离和能量耗散方案之间进行选择，而无需迭代分析。在即将发表的一篇论文中，该方法被纳入了地震隔离桥梁的基于变形的设计方法中。GDE 构成了代码通常采用的等效线性化方法的替代方案，告知在替代隔离和能量耗散方案之间进行选择，而无需迭代分析。在即将发表的一篇论文中，该方法被纳入了地震隔离桥梁的基于变形的设计方法中。