动力机器地基基础振动研究

发布时间：2018-05-30 11:52

本文选题：动力机器 + 层状地基　；参考：《广西科技大学》2015年硕士论文

【摘要】：随着工业技术及我国社会经济迅速发展,像一些如超高压压缩机、高转速汽轮机等等这样的大型动力机器的应用越来越普遍。这种大规模的动力机器需要一个稳定的基础支持,所以动力机器基础的设计已经成为整个工厂设计的重要部分。其设计标准要求许多方面都满足要求(如环保和工业布置等),因此要严格限制基础振动的频率。动力机器在运转时,会产生较大的振动,过大的振动会影响到一些仪器、设备的正常运行,还会影响到周围环境,所以,机器基础的设计要合理,必须使在正常工作中可能出现的振动位移限制在允许范围之内。本文参照国内外有关文献以及在前人研究成果的基础上进行了如下研究:首先对动力机器基础竖向振动进行研究,根据弹性半空间理论建立波动方程,然后依据积分变换(Hankel变换和反变换),并结合边界条件导出了半空间表面上基础竖向振动的运动方程;其次,基于弹性动力学基本理论,采用Fourier变换理论,推导了两节点谱单元和单节点谱单元;然后考虑层间完全连续,建立了n层土体结构的整体刚度矩阵,研究了动力荷载作用下层状土体的动力响应问题。最后进行机器基础和地基协同工作的动力分析:①分析了天然地基动力参数,利用弹性半空间计算模式实用化法进行天然地基动力参数计算,将其结果与规范规定得出的结果进行了比较;②建立有限元模型,研究动力机器基础与地基协同工作的动力分析。通过以上研究,本文得到了机器基础竖向振动的运动方程;推导出了单节点谱单元和双节点谱单元,得出基础底面各点竖向位移由于底层模量、层厚及荷载频率的不同而受到的影响规律;根据机器基础和地基相互作用的分析,得出在机器基础设计时考虑地基基础相互作用的重要性;根据机器基础的动力分析,得出最大振动线位移发生的规律特征,可推测出动力机器在正常工作中有可能出现的共振区域,尽可能的使外部激励远离这部分共振区域,避免使其出现共振。
[Abstract]:With the rapid development of industrial technology and China's social economy, the application of some large power machines such as ultra-high pressure compressors, high speed steam turbines and so on is becoming more and more common. This kind of large-scale power machine needs a stable foundation support, so the design of power machine foundation has become an important part of the whole plant design. The design standard requires many aspects to meet the requirements (such as environmental protection and industrial layout, etc.), so the frequency of foundation vibration should be strictly limited. When the power machine is in operation, it will produce larger vibration, too much vibration will affect the normal operation of some instruments, equipment, and the surrounding environment. Therefore, the design of the machine foundation should be reasonable. Vibration displacements that may occur during normal operation must be limited to the allowable range. In this paper, the following studies are carried out on the basis of domestic and foreign literatures and previous research results: firstly, the vertical vibration of the power machine foundation is studied, and the wave equation is established according to the elastic half-space theory. Then, according to the integral transformation and inverse transformation, and combining with boundary conditions, the motion equations of vertical vibration of foundation on the surface of half-space are derived. Secondly, based on the basic theory of elastic dynamics, the theory of Fourier transformation is adopted. Two point spectral elements and one point spectral element are derived, and then the global stiffness matrix of n-story soil structure is established considering the complete continuity between layers, and the dynamic response of layered soil under dynamic load is studied. Finally, the dynamic analysis of the machine foundation and the foundation is carried out. The dynamic parameters of the natural foundation are analyzed by 1: 1, and the dynamic parameters of the natural foundation are calculated by the practical method of elastic half-space calculation. The finite element model is established to study the dynamic analysis of dynamic machine foundation and foundation. Through the above research, the motion equation of vertical vibration of machine foundation is obtained, and the single node spectral element and the double node point spectrum element are derived, and the vertical displacement of each point on the bottom surface of the foundation is obtained due to the underlying modulus. According to the analysis of the interaction between the machine foundation and the foundation, the importance of considering the interaction between the foundation and the foundation in the design of the machine foundation, the dynamic analysis of the machine foundation, The characteristics of the maximum vibration line displacement are obtained, and the resonance region which may occur in the normal operation of the power machine can be inferred, and the external excitation is far away from this part of the resonance region as far as possible, and the resonance can be avoided.
【学位授予单位】：广西科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU476.1

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