基于激光测距仪的薄壳结构初始缺陷测量系统

薄壳结构的屈曲通常对初始缺陷十分敏感,因此对几何初始缺陷的精确测量是高质量的壳体屈曲试验的必要环节。本研究旨在开发一套基于激光测距仪的初始缺陷测量系统,以实现对壳体结构的快速、精确、非接触的测量。本文详细介绍该系统的设计思想及实现方法,包括激光测距仪的选择、转动与直线运动的实现、数据采集与计算机自动控制技术等。利用该系统对两个柱支承钢筒仓模型进行了仔细的初始缺陷三维测量,验证了系统的适用性和可靠性。文中还提出了利用二重傅立叶分解技术分析实测缺陷的方法。本文成果与方法为薄壳结构屈曲试验奠定了基础。

An Imperfection Measurement System for Thin-Shell Structures Based on a Laser Displacement Meter

Buckling of thin shells is generally sensitive to geometric imperfections,so precise surveys of initial geometric imperfections are essential for high quality shell buckling experiments.This study aims to establish an experimental facility for imperfection measurement employing a laser displacement meter,which can provide fast,accurate and non-contact measurement for shell structures.The design consideration and development of the measurement system is described,including the selection of laser displacement meter,realization of rotational andlinear motion,and techniques for data acquisition and computer control.Threedimensional surveys are carefully conducted on two column-supported steel silo models using the present system,and its applicability and reliability is verified.A method for the analysis of measured imperfections utilizing the doubleFourier decomposition technique is also proposed.Results from this study provide important basis for buckling experiments of thin shell structures.