This study introduces simple piecewise linearisation in time series (SPLiTS), for time‐domain inversion (TDI) to estimate the physical parameters of nonlinear structures. SPLiTS considers a nonlinear structure to be a set of piecewise linearised structures based on each half‐cycle wave in the displacement response data. For the linearisation, SPLiTS intentionally minimises the effect of the central point shift that damaged structures commonly display. After theoretically introducing SPLiTS to the response data of single‐/multi‐degree‐of‐freedom (SDOF/MDOF) structures, parameter estimations are performed for data obtained from numerical simulations and experiments. The efficiency of consideration of the central‐point shift is demonstrated in parameter estimations for numerical simulations where response data are obtained by a nonlinear SDOF structure having a trilinear hysteretic spring. SPLiTS is then applied to experimental data from shaking table tests, in which a specimen, imitating a one‐storey structure, displayed yielding behaviour. TDI with SPLiTS reasonably estimates physical parameters that show increased damping and decreased stiffness in time series at the inelastic range. Next, SPLiTS is applied to experimental data from shaking table tests conducted for a full‐scale, three‐storey structure at E‐Defense in 2013. The damping coefficient and stiffness of each storey are reasonably estimated for the specimen under different amplitudes. For these experimental data, estimated structural energy absorption calculated by damping in the time series corresponds well with the structural damage of the specimens. Thus, structural energy absorption is proven to be a useful index for indicating structural damage.

中文翻译：

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时间序列中的时间序列简单分段线性化，以估计非线性结构的物理参数

本研究介绍了时间序列中的简单分段线性化（SPLiTS），用于时域反演（TDI）以估计非线性结构的物理参数。SPLiTS根据位移响应数据中的每个半周期波将非线性结构视为一组分段线性化的结构。对于线性化，SPLiTS故意将损坏的结构通常显示的中心点偏移的影响最小化。从理论上将SPLiTS引入单/多自由度（SDOF / MDOF）结构的响应数据后，将对通过数值模拟和实验获得的数据进行参数估计。在数值模拟的参数估计中证明了考虑中心点偏移的效率，其中数值响应是通过具有三线性滞后弹簧的非线性SDOF结构获得的。然后将SPLiTS应用于振动台测试的实验数据，在该数据中，模仿一层结构的标本显示出屈服行为。带有SPLiTS的TDI合理地估计了物理参数，这些参数在非弹性范围内按时间序列显示出增加的阻尼和降低的刚度。接下来，将SPLiTS应用于2013年在E-Defense进行的针对三层全尺寸结构的振动台测试的实验数据。合理估算了不同振幅下样品的各层的阻尼系数和刚度。对于这些实验数据，通过时间序列中的阻尼计算得出的估计结构能量吸收与样品的结构损伤非常吻合。因此，事实证明，结构能吸收是指示结构破坏的有用指标。