基于桥梁结构动力特性的静力性能预测

桥梁荷载试验法是对桥梁结构工作状态进行直接测试的一种检定手段,通过动、静荷载试验测试出桥梁结构的各种动、静载响应,评定桥梁实际承载能力和受力性能,是评价桥梁性能最可靠的一种方法。基于环境振动的动载试验具有无须贵重的激励设备,不打断结构的正常使用,方便省时,只需测定响应数据等优点,已经广泛的应用于桥梁结构检测之中。静载试验通常所需要的周期长、费用大、评定结果稳定可靠,而动载试验相对来讲周期短,费用较小,并且对于多跨桥梁可以评价整桥的结构性能,各有优缺点。本文基于环境振动试验测试桥梁在动载作用下的响应,得到桥梁的频率、阻尼和振型等模态参数,将桥梁结构的模态参数和静载试验结果相互联系起来,用结构的模态参数来预测结构的承载能力,对结构的可靠性进行评估,从而可以减少结构荷载试验的费用。

The Static Characters Forecast by Dynamical Parameters of Structures

Loading test method is a tool for checking and assessment bridge structural active state.By dynamical and static loading test the responses of bridge can be obtained,which can be used to assess the practical carrying capacity and stress performance of structures.The loading test is the most reliable method for assessing the performance of bridge.The static tests usually need more time and cost.But ambient bridge vibration test has an advantage of being simple,fast and cheap,which be implemented by only measuring the responses data.The ambient vibration test had been extensive used in bridge structural detection.This paper proposed a new analysis method which will forecast the structural static characters by the dynamical parameters of structures.This method can reduce the loading test cost.The structural performance can be forecasted only by the dynamical parameters.At first the structural dynamical parameters,for example frequencies,damping and model shape,can be obtained from the ambient test of structures.Then the relation between the static characters and dynamical parameters will be established.At last the static performance can be forecasted by the dynamical parameters.