This paper aims at presenting the guidelines to follow in order to set up an identification procedure which is able to determine the axial force, the flexural rigidity and the rotational end stiffnesses of slender and tensioned structural elements, based on measurements of their natural frequencies and mode shapes. First of all, when such an element is slightly affected by bending stiffness effects, perturbation methods can be applied to get a composite approximation for its natural frequencies and an asymptotic expression for its mode shapes. These simple analytical formulas allow to understand the role played by each model parameter in the modal response and show that the axial force, the flexural rigidity and the rotational end stiffnesses can be correctly identified under some conditions, which are established and provided in this document. Among others, it is necessary that the identification procedure relies on the first few natural frequencies and mode shapes, which are measured near each extremity of the element, as well as some natural frequencies associated with higher modes.

本文旨在提出要遵循的准则，以建立一个识别程序，该程序能够根据对细长和张拉结构元件的固有频率和模态的测量来确定其轴向力、弯曲刚度和旋转端刚度。形状。首先，当这种单元受到弯曲刚度效应的轻微影响时，可以应用微扰方法来获得其固有频率的复合近似值和其模态振型的渐近表达式。这些简单的分析公式可以理解每个模型参数在模态响应中的作用，并表明在某些条件下可以正确识别轴向力、弯曲刚度和旋转端刚度，这些条件在本文档中建立和提供。