中文摘要：

以桥梁模态测试研究为工程背景,为解决桥梁模型模态测试中常规激振装置存在的不足,研制了一种小型惯性式激振器。该激振装置主要由步进电机、驱动器、控制器、齿轮传动部件、一对偏心质量块及底座组成。对某大跨度悬索桥模型进行激振,通过动力放大系数峰值处激振频率确定共振时模态频率,并与ANSYS有限元模型计算、锤击自由振动实验结果对比,证明了该激振器在桥梁模型模态测试中的适用性。该激振器具有质量轻、体积小、激振频率精准可控的特点,除在模型模态测试中的应用,还为实验教学及实际桥梁的激振提供了新的思路和方法。

英文摘要：

This paper presents the design,structure and test results of a new small-scale inertial vibration exciter. Under the engineering background of the modal tests of bridges,this paper describes the development of the exciter to solve some deficiencies of ordinary exciters. The device is made of stepping motor,motor driver,motor controller,gear set,counter-rotating dual-rotor and base. According to the modal test of a long-span suspension bridge model,the resonance modal frequency is determined by the frequency in which the dynamic magnification factor is maximum,and the test results of the inertial vibration exciter are compared with those of numerical calculation of ANSYS and hammering tests.It proves that this new small-scale inertial vibration exciter is applicative to the modal tests of bridge models. With the advantages of lightness,small volume and precisely controllable frequency of force,this exciter not only is applicative in modal tests of bridge models but also provides new idea and method for experiments teaching as well as excitation of real bridges.