New Scenario-Based Cumulative Absolute Velocity Models for Shallow Crustal Tectonic Settings
New Scenario-Based Cumulative Absolute Velocity Models for Shallow Crustal Tectonic Settings
复制标题
新的基于情景的浅地壳构造环境累积绝对速度模型
DOI：
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Chenying Liu
中科院分区：
文献类型：
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作者：
J. Macedo;N. Abrahamson;Chenying Liu
太平洋地震工程研究中心的下一代衰减-West 2数据库被用来推导一个新的条件地面运动模型（CGMM）和一组用于估计地壳浅部构造环境中地震的累积绝对速度（CAV）的基于ARBO的模型。进行随机效应回归以开发条件模型，其中随机效应跨越不同的地震。CAV的估计取决于估计的峰值地面加速度（PGA）、顶部30 m处的时间平均剪切波速度（VS 30）、地震震级（Mw）和破裂距离（Rmax）。通过结合条件CAV模型与地震动模型（GMM）在地壳浅部地震带PGA，新的基于ARMIO的模型估计的中值CAV及其标准差，直接从地震场景和场地条件。一个基于CAVO的CAV模型固有地捕捉复杂的地面运动的缩放效应，包括在GSTMI的频谱加速度，它是基于，如沉积物的深度效应，土壤的非线性效应，和区域化的影响。该方法还确保了估计的CAV值与设计谱加速度反应谱之间的一致性。介绍了CAV的条件模型和基于神经网络的CAV估计模型，并比较了基于神经网络的CAV估计模型和传统CAV估计模型的发展趋势。有趣的是，我们发现一个显着的一致性之间的基于MIMO和传统的无条件CAV模型，当底层的频谱GMM用于实现的基于MIMO的模型是适当的约束。最后，我们提供的例子中使用的条件和基于神经网络的模型在基于性能的地震工程。
The Pacific Earthquake Engineering Research Center Next Generation Attenuation-West2 database is used to derive a new conditional ground-motion model (CGMM) and a set of scenario-based models for estimating cumulative absolute velocity (CAV) for earthquakes in shallow crustal tectonic settings. Random-effects regressions were performed to develop the conditional model, with random effects across different earthquakes. The estimate of CAV is conditioned on the estimated peak ground acceleration (PGA), the time averaged shear-wave velocity in the top 30 m (VS30), the earthquake magnitude (Mw), and the rupture distance (Rrup). By combining the conditional CAV model with ground-motion models (GMM) in shallow crustal earthquake zones for PGA, new scenario-based models are developed for estimating the median CAV and its standard deviation, directly from an earthquake scenario and site conditions. A scenario-based CAV model captures inherently the complex ground-motion scaling effects included in the GMMs for spectral accelerations on which it is based on, such as, sediment-depth effects, soil nonlinearity effects, and regionalization effects. This approach also ensures consistency between the estimated CAV values and a design spectral acceleration response spectrum. The conditional and scenario-based models to estimate CAV are presented, and trends of the developed scenario-based models and previous traditional models for CAV are compared. Interestingly, we found a remarkable consistency between scenario-based and traditional nonconditional CAV models, when the underlain spectral GMM used in the implementation of the scenario-based model is properly constrained. Finally, we provide examples for the use of the conditional and scenario-based models in performance-based earthquake engineering.