【作者】 阎玉芹；

【导师】 程林；

【作者基本信息】 山东大学 ， 机械设计及理论， 2011， 博士

【摘要】 塔式起重机作为一类典型的大型工程机械,属于建筑施工中的一种高危特种设备。塔机发生故障,不仅需要专业人员进行维修、维护、机械停工,造成较大的经济损失,而且,一旦塔机发生倒塔事故,极有可能发生群死群伤的特大事故。塔机安全问题不仅涉及到个体生命的安全与健康,而且对社会稳定和经济发展也有着极为重要的影响。对塔机进行健康监测,及时发现塔机存在的安全隐患,提高塔机运行的可靠性,减少或消除事故,已成为业内关注的焦点问题。本文结合国内外结构健康监测领域的发展现状及研究热点,以实现塔式起重机钢结构在线损伤诊断为目的,对塔机钢结构损伤诊断技术进行了深入系统的研究,取得了以下成果：(1)对塔机塔身顶端倾角模型进行了系统研究。以塔身顶端倾角为特征量,建立了塔机正常状态顶端倾角特征模型；分析并建立了正常空载状态下塔身顶端倾角特征模型以及塔身钢结构损伤状态下顶端倾角特征模型；以此为基础建立了塔身钢结构损伤方位判断的倾角特征模型；研究了该模型的实现算法；通过实验验证了所建模型的正确性。建立的模型便于实现实时控制,可以作为一种控制模型使用。(2)提出了塔机钢结构完好状态的判断准则；建立了基于时间序列分析的塔机钢结构完好状态诊断时序刚度距模型、严重超载状态识别的时序刚度距模型以及人员违规操作识别的时序刚度距模型；编写了模型的Matlab程序。所建模型能够实现塔机钢结构损伤、严重超载以及人员违规操作等情况的识别。(3)系统研究了基于支持向量机的塔机钢结构损伤诊断方法。系统分析了位移变化率对结构损伤的灵敏程度。提出了基于位移变化率和支持向量机的塔机钢结构损伤识别方法。将位移变化率作为支持向量机的输入量,对塔机的塔身钢结构损伤进行诊断,获得了很好的损伤识别效果。(4)对塔机钢结构损伤诊断的实验研究。通过对采用高强螺栓连接的两个塔身标准节用主弦杆(主肢)模型进行损伤实验以及工地现场塔机整机实验,验证了用倾角测量传感器测得的塔身顶端倾角值作为特征量,进行塔机钢结构损伤识别的可行性,并证明了本文提出的基于位移变化率和支持向量机的塔机钢结构损伤诊断方法的有效性。(5)系统设计了塔式起重机综合监测系统,并开发了系统的管理软件。所开发的塔机综合监测系统集结构监测、健康诊断、管理评估于一体；能够实现塔机钢结构损伤的实时识别、塔机工作环境和使用过程各项性能指标的实时监控。开发的系统管理软件具有强大的数据管理功能,实现了结果的可视化；软件平台界面友好,操作简便。更多还原

【Abstract】 As a kind of typical large engineering machinery, the tower crane is high risky special equipment. It can cause tremendous economic loss because of the work of professionals to maintain and the shutdown of the machine when the tower crane goes wrong; more importantly, it can also cause fatal accidents when the tower crane falls down. The security problem of tower cranes will influence not only the individual safety and health, but also the social stability and economic development. It has become the focus to monitor health condition of the tower crane, find out the potential safety hazard on time, improve operation reliability and reduce or eliminate accident.In this paper, aimed at the online steel structural damage diagnosis of tower cranes, deeply and systematically researches are carried out for steel structural damage diagnosis of tower cranes by combining the current situation and the research focus of structural health monitoring. The main results are described as follows:Firstly, the tower body top inclination model is studied systematically. The tower body top inclination feature model, which characterizes the top inclination, is established in normal state; the tower body top inclination feature model in normal and no loading state and in steel structural damage state of tower bodies are analyzed and established. On the basis of this model, the top inclination feature model which can recognize the steel structural damage orientation of the tower body is established, too; and the implementation arithmetic of this model is investigated. The validity of this model is testified by experiments. This model is easy to realize real-time control, and it can be used as a kind of control model.Secondly, the judgment criterion of steel structural sound condition of tower cranes is proposed. Based on the time series method, the time series stiffness spacing model, which can recognize the steel structural sound condition, overloading state and violation operation, is established. The Matlab program for this model is compiled.Thirdly, the steel structural damage diagnosis method of tower crane based on support vector machine is investigated. The sensitivity of changing ratio of displacement to structural damage is analyzed. The steel structural damage diagnosis method based on the changing ratio of displacement and support vector machine is proposed. The changing ratio of displacement is taken as input data to diagnose the steel structural damage of tower crane; the effect of indentifying damage is good.Fourthly, the damage diagnosis test for the steel structure of tower cranes is carried out under ambient vibration. The feasibility of using the top inclination data of tower bodies measured by the inclination sensor as the output characteristic quantity to recognize the steel structural damage is testified by two experiments; one is the damage experiment of two main chords connected by high-strength bolt and the other is the damage experiment of the whole tower crane used in construction site. The validity of the steel structural damage diagnosis method, based on the changing ratio of displacement and the support vector machine, is verified in this paper.Fifthly, the integrated monitoring system of tower cranes is designed systematically, and the management software is developed. This system consists of functions such as the structure monitoring, health diagnosis and management evaluation; and it can recognize the steel structural damage of tower cranes and monitor the work environment and each performance index of tower cranes in real-time. The management software developed has powerful ability of data process, and can realize results visualization; also, this software has a friendly interface and is easy to operate.更多还原