《Earthquake Engineering and Structural Dynamics》杂志刊登“装有类似隔震装置轴承组件的公路桥抗震性能研究”

作者：Evgueni T. Filipov,  Jessica R. Revell, Larry A. Fahnestock,  James M. LaFave, Jerome F. Hajjar,  Douglas A. Foutch, Joshua S. Steelman

刊物：《Earthquake Engineering and Structural Dynamics》，2013年，42卷第9期，1375-1394页

关键词：隔震；类似隔震装置；公路桥；滑动轴承；地震响应时程分析

摘要：在伊利诺斯州，现代公路桥上一般都装有允许上部结构热运动的经济弹性轴承、钢固定轴承，以及能够限制正常使用下产生大变形的横向保护器。地震发生时，轴承系统能够提供类似隔震的作用，滑动的轴承能够引起周期的延长，从而降低了下部结构所受荷载。本文建立了一个与预期非线性行为校准过的计算模型，对其参数进行了研究，其可以用于评价类似隔震的桥梁行为。同时调查了不同上部结构形式、下部结构形式、下部结构高度、基础类型以及弹性轴承类型。随后，在新马德里地震带发现只有很少的桥梁省略了设计地震输入，这也表明大多数伊利诺斯州的结构在其设计周期内没有经受过严重损伤。然而，在某种情况下，由于省略了中等和强地震输入的Ⅱ型轴承系统（包括了弹性支撑和PTFE滑动器）而导致了临界损伤。由很多桥梁案例的损伤序列可知，支墩的屈服发生在低水平地震激励条件下。这是由于高强度固定轴承构件造成的，也进一步证明校准类似隔震设计方法的合理性。最后发现地震动类型、桥墩高度、轴承类型都能显著的影响整体桥梁响应。

Seismic performance of highway bridges with fusing bearing components for quasi-isolation

Authors: Evgueni T. Filipov, Jessica R. Revell, Larry A. Fahnestock, James M. LaFave, Jerome F. Hajjar,  Douglas A. Foutch, Joshua S. Steelman

Journal: Earthquake Engineering and Structural Dynamics, Volume 42, Issue 9, pages1375-1394, 25 July 2013

Key words: seismic isolation; quasi-isolation; highway bridges; sliding bearings; earthquake response history analysis

Abstract: Modern highway bridges in Illinois are often installed with economical elastomeric bearings that allow for thermal movement of the superstructure, and steel fixed bearings and transverse retainers that prevent excessive movement from service-level loadings. In the event of an earthquake, the bearing system has the potential to provide a quasi-isolated response where failure of sacrificial elements and sliding of the bearings can cause a period elongation and reduce or cap the force demands on the substructure. A computational model that has been calibrated for the expected nonlinear behaviors is used to carry out a parametric study to evaluate quasi-isolated bridge behavior. The study investigates different superstructure types, substructure types, substructure heights, foundation types, and elastomeric bearing types. Overall, only a few bridge variants were noted to unseat for design-level seismic input in the New Madrid Seismic Zone, indicating that most structures in Illinois would not experience severe damage during their typical design life. However, Type II bearing systems, which consist of an elastomeric bearing and a flat PTFE slider, would in some cases result in critical damage from unseating at moderate and high seismic input. The sequence of damage for many bridge cases indicates yielding of piers at low-level seismic input. This is caused by the high strength of the fixed bearing element, which justifies further calibration of the quasi-isolation design approach. Finally, the type of ground motion, pier height, and bearing type were noted to have significant influence on the global bridge response.

原文链接：http://onlinelibrary.wiley.com/doi/10.1002/eqe.2277/abstract