基于梁体转角的高速铁路桥梁挠度测试方法研究

高速铁路桥梁设计由刚度控制,国内外规范多以设计荷载作用下的挠度作为限值指标。传统挠度测试方法对高速铁路桥梁存在适用性问题,通过倾角仪测量梁体转角以及简化振型函数法拟合得到桥梁挠度的方法,为高速铁路桥梁准静态挠度测量提供了一种新手段。对简化振型函数法进行有限元模型验证,建立包含数据采集和分析的测试系统,并进行现场试验验证。结果表明:基于梁体转角拟合的桥梁挠度测试方法能够满足工程上的对桥梁挠度测试的要求,测试系统不受桥梁跨度和地形的影响,可以用来测试跨越江河和峡谷等桥下较难以安装传统挠度测量传感器的大跨度桥梁的准静态挠度,测试系统适用性较强。

High Speed Bridge Deflection Measurement Based on Rotation Angle of Beam Body

Rigidity is a controlling parameter for the design of high speed bridges and the deflection under the design load is regarded as a limit indicator in domestic and overseas specifications of its kind. Since the traditional deflection measurement is not adaptable to high speed railways, a new measurement is provided in the paper by using the Inclinator to measure the rotation angle of the beam body and combing the simplified vibration mode function to get the deflection of bridge. The simplified vibration function is verified via the finite element model, and a test system integrating data acquisition and analysis is also established. The field test verification shows that the deflection measurement based on the rotation angle of the beam body fulfills related requirements;the test system is immune from the large bridge span and challenging geological conditions, so this method can be used to measure the quasi-static deflection of bridges crossing rivers and valleys where the traditional deflection measurement sensors cannot be installed and make measurement.