For rational solutions against seismic excitations of masonry bridges, the capability of 3D soil–structure interaction (SSI) modeling with experimental evidence has been insufficiently researched up to now. This is also valid for the effects of near- and far-fault earthquakes. Hence, the spectral responses measured by microtremors have been compared with the ones of 3D SSI analysis under the effects of near- and far-fault earthquakes for a historical masonry arch bridge in this article. The 3D SSI modeling of bridge and substructure soil was built with elastic finite element model using solid element and viscous boundary. The SSI analysis has been performed by direct approach using time-history analysis. The earthquake motions (near fault, far fault) were selected in accordance with the tectonic setting of the bridge’s region. From the study, it is possible to confirm that microtremors are able to detect spectral responses of the bridge by the presence of SSI influences. By the evidence of amplifications and soil–structure resonance, the microtremor measurements experimentally promise that: (i) the bridge can be adequately identified by SSI analysis compared to fixed base, (ii) the elastic model can satisfactorily provide information about the bridge’s responses (amplitudes, spectral response, stress distribution) under earthquake effect, and (iii) the far-fault motion especially due to SSI modeling is significant for the seismic responses. The study indicates that regarding the SSI influences into seismic computation has become quite efficient for determination of a possibility of various adverse effects (high displacements, critical stresses, resonance). Moreover, diagnosing the historical bridge well as a result of microtremors together with SSI modeling strongly proposes protection of the bridge with an appropriate retrofitting.

中文翻译：

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近断层地震和远断层地震作用下砌体拱桥的微震测量和3D动态土-结构相互作用分析

对于针对砌体桥梁地震激励的合理解决方案，到目前为止，尚未充分研究具有实验证据的3D土-结构相互作用（SSI）建模的能力。这对于近断层和远断层地震也是有效的。因此，本文将历史建筑砌体拱桥在近震和远震的影响下，通过微震测量的光谱响应与3D SSI分析进行了比较。桥梁和下部结构土的3D SSI建模是利用实体单元和粘性边界的弹性有限元模型建立的。SSI分析已通过使用时程分析的直接方法进行。根据桥梁区域的构造背景选择了地震运动（近断层，远断层）。从研究中 有可能证实微震能够通过存在SSI影响来检测桥梁的光谱响应。通过放大和土壤结构共振的证据，微震测量通过实验证明：（i）与固定基础相比，可以通过SSI分析充分识别桥梁，（ii）弹性模型可以令人满意地提供有关桥梁反应的信息（地震作用下的振幅，频谱响应，应力分布），以及（iii）尤其是由于SSI建模引起的远断运动对于地震响应具有重要意义。研究表明，对于SSI而言，地震计算的影响对于确定各种不利影响（高位移，临界应力，共振）的可能性已经变得非常有效。此外，