Seismic demand models for probabilistic risk analysis of near fault vertical ground motion effects on ordinary highway bridges
Seismic demand models for probabilistic risk analysis of near fault vertical ground motion effects on ordinary highway bridges
复制标题
DOI：
10.1002/eqe.1123
复制
发表时间：
2012-02
影响因子：
4.5
通讯作者：
Zeynep Gulerce;E. Erduran;S. Kunnath;N. Abrahamson
中科院分区：
文献类型：
--
作者：
Zeynep Gulerce;E. Erduran;S. Kunnath;N. Abrahamson
竖向地震动对公路桥梁地震反应的影响还不是很清楚。最近的研究表明，竖向地震动可以大大增加桥梁柱和梁的力和力矩需求，在桥梁结构的抗震设计中不能忽视。为了评估竖向地震动对单弯两跨公路桥响应的影响，需要结合关键工程需求参数（EDP）和地震动强度测量（IM）进行系统研究。一个参数研究的范围内的公路桥梁配置进行选定的水平和垂直地面运动的结果被用来确定结构参数，显着放大的垂直激励。这些参数中的放大使用简单的方程来建模，该方程是桥梁相应水平和垂直基本周期处的水平和垂直谱加速度的函数。本文介绍了推导地震需求模型开发的典型公路立交桥的关键EDPs和水平和垂直地面运动IM的综合影响，取决于类型的参数和结构的周期。这些模型可以单独用作基于风险的设计工具，以确定超过预定水平的地面震动的EDP临界水平的概率，或者可以明确地包括在概率地震风险评估中。版权所有© 2011约翰威利父子有限公司.
The influence of vertical ground motions on the seismic response of highway bridges is not very well understood. Recent studies suggest that vertical ground motions can substantially increase force and moment demands on bridge columns and girders and cannot be overlooked in seismic design of bridge structures. For an evaluation of vertical ground motion effects on the response of single‐bent two‐span highway bridges, a systematic study combining the critical engineering demand parameters (EDPs) and ground motion intensity measures (IMs) is required. Results of a parametric study examining a range of highway bridge configurations subjected to selected sets of horizontal and vertical ground motions are used to determine the structural parameters that are significantly amplified by the vertical excitations. The amplification in these parameters is modeled using simple equations that are functions of horizontal and vertical spectral accelerations at the corresponding horizontal and vertical fundamental periods of the bridge. This paper describes the derivation of seismic demand models developed for typical highway overcrossings by incorporating critical EDPs and combined effects of horizontal and vertical ground motion IMs depending on the type of the parameter and the period of the structure. These models may be used individually as risk‐based design tools to determine the probability of exceeding the critical levels of EDP for pre‐determined levels of ground shaking or may be included explicitly in probabilistic seismic risk assessments. Copyright © 2011 John Wiley & Sons, Ltd.