大气除尘装备支承钢结构墙板—立柱结构体系承载机理与设计理论研究

The air dust precipitator is the key environmental protection facility to eliminate the dust in atmosphere which is widely used in the industries of power plant, metallurgy, chemical engineering and building material. At present, since the configuration and loads of the bearing steel structure of dust precipitator are very complex, the load bearing mechanism and design theory of precipitator steel structure have been lack of research. Focusing on the structural system composed of stiffened steel wall and column of dust precipitator casing, in sufficient consideration of initial geometrical imperfections and residual stress, two problems are investigated by the combined methods of test, finite element computation and theoretical analysis. Firstly, in consideration of the diaphragm effect of stiffened steel plate wall of casing, the stability of column is investigated and the stability design methods system is produced. Secondly, the stability of stiffened steel wall of casing subjected to combined loads is investigated, and then the corresponding design and evaluation methods are produced. The research results will improve the structural theory of diaphragm supported structral system. Besides, the research results will produce the scientific bases to the constitution of structural design specification of dust precipitator and will be great helpful to heighten the design and manufacture level of environmental protection facility. In a word, this research has both the great theoretical significance and the great engineering application value.

大气除尘装备是广泛应用于电力、冶金、化工和建材等行业的用于消除烟尘的重要环保装备。除尘装备支承钢结构构造与荷载情况复杂，目前对其承载机理和结构设计方法研究较少。本项目围绕除尘装备壳体的加劲钢板墙板-立柱结构体系，采用试验研究、有限元数值计算和理论分析等方法，充分考虑初始几何缺陷和残余应力影响，研究在考虑加劲钢墙板蒙皮作用时壳体立柱稳定性，提出立柱稳定性设计方法体系；研究处在复杂荷载作用下的壳体加劲钢墙板稳定性，提出墙板稳定性设计计算方法。研究成果将发展和完善蒙皮支撑结构体系的结构理论和设计方法，为制定除尘装备钢结构设计规范提供科学依据，对于提高我国环保装备设计制造水平，保护环境具有重要的理论意义和工程应用价值。

本项目以我国大气除尘装备壳体围护结构为研究背景，结合其结构特征、荷载情况与工艺特点，采用理论分析、数值计算和试验研究的方法，研究了除尘器壳体围护结构采用墙板-立柱结构体系时，立柱的稳定性、壳体围护墙板的承载性能、壳体顶梁的优化设计方法以及壳体底部灰斗支承梁的承载性能。充分考虑壳体墙板对于骨架立柱的受力蒙皮作用，探索初始几何缺陷和焊接缺陷对于壳体立柱稳定性的影响，明确了最不利缺陷形式，在此基础上发展了用于壳体立柱稳定性研究的数值计算模型。明确了墙板、立柱构造和荷载情况对于壳体立柱在仅受轴压、仅受横向荷载以及轴向和横向荷载共同作用时稳定性的定量影响规律，总结提出了壳体立柱稳定性设计建议。研究了加劲钢板和压型钢板墙板发挥受力蒙皮作用时的破坏形式，以及结构参数对于墙板承载能力的影响规律，提出了墙板承载能力的计算建议。研究了利用壳体顶部保温箱的结构作用以改造壳体顶梁的优化设计方法，提出了内力计算方法、最不利荷载情况、优化后梁系合理构形，就承载性能较为复杂的下弦拉弯构件的承载性能展开深入研究，对其加劲肋强度、加劲肋布置和稳定性设计提出建议。进行了灰斗底梁承载性能试验，结合计算与分析结果，提出了底梁稳定性和强度设计建议。本项目研究既为除尘装备支承结构设计提供了可靠合理的设计计算方法，提高了除尘装备设计制造的安全性和经济性；同时发展了蒙皮支撑结构承载理论，因此具有工程实践价值和学术理论意义。