摘要
地震荷载下桥梁间的相互碰撞是一个复杂的非线性过程。通过对正弦荷载和10个地震荷载下的响应分析,提出了用一个简化的线性计算方法(等效位移阻尼法)来分析这一复杂的碰撞过程。等效位移阻尼法是从最大位移等效的角度,用一个具有等效位移阻尼比的线性无碰撞体系来简化非线性的桥梁碰撞系统的计算方法。其中的等效位移阻尼比是伸缩缝间距、结构动力特性和地震荷载特性的函数。等效位移阻尼比的设计公式是通过对1个简单的碰撞体系在10个地震荷载下的反应统计分析得出的。并且通过对实桥A-237R的有限元分析,验证了这一公式的准确性和实用性。
Pounding between bridges is a complicated non-linear effect under strong earthquakes.An equivalent displacement damping concept to simplify linear analysis of the bridge systems in a harmonic and 10 earthquake excitations is developed.Equivalent displacement damping method is to capture the max displacement of the nonlinear pounding system with using a linear non-pounding analysis.The equivalent displacement damping is a function of the gap width between bridges,also the characteristics of earthquake excitations and system.Design equations for equivalent damping were developed under various conditions of 10 earthquake excitations.Bridge A-237R was used to verify the design equations for engineering accuracy.
引文
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