Performance of Suspension Bridges During Strong Earthquake

在本项目中， 文森特号上和附近的加速度计 1987年惠蒂尔地震期间的托马斯桥将被 研究了 该研究将：（一）确定代表性和 适当相关的非同步支撑运动，（ii） 验证现有的分析模型和地震分析，㈢ 开发系统识别技术， 多输入多输出模型（线性和 非线性），（iv）评估桥梁在 地震，（五）优化仪器的回报 投资和提高记录响应的有用性 （六）提出一个总体方案，加强或 现有缆索支撑桥梁的改造，（vii）获得 阻尼值的信息作为振动的函数， 振幅，（八）获得有关土壤结构的信息 这种大规模结构相互作用，（ix）发展弹性 塞子或其他特殊装置，以抑制 地震和风力。 这项研究将满足对全面 对这些独特的历史响应记录的调查 为了确保吊桥的安全， 在全国地震带广泛使用。 研究 结果对于加强现有的 缆索支撑桥梁（以及设计新结构， 以及升级和安装新的监控 仪器）。

In this project the strong motion records taken from the 26 accelerographs located on and in the vicinity of the Vincent Thomas Bridge during the 1987 Whittier Earthquake will be studied. The study will: (i) define representative and appropriately correlated non-synchronous support motions, (ii) validate existing analytical modelling and seismic analysis, (iii) develop system identification techniques that deal with multiple-input multiple-output models (both linear and nonlinear), (iv) evaluate the bridge performance during the earthquake, (v) optimize the return on the instrumentation investment and improve the usefulness of the recorded-response data, (vi) propose a general program for strengthening or retrofitting of existing cable-supported bridges, (vii) obtain information on damping values as a function of the vibrational amplitudes, (viii) obtain information on the soil-structure interaction of this massive structure, (ix) develop elastic stoppers or other special devices to dampen the effects of seismic and wind forces. The study will fulfill an urgent need for comprehensive investigations of these unique and historical response records to insure the safety of suspension bridges which have been widely in use across the nation's seismic zones. The research results will be of extreme importance to strengthen existing cable-supported bridges (as well as to design new structure, and for up-grading and installing new monitoring instrumentation).