火电厂钢筋混凝土侧煤仓结构的抗震性能分析

发布时间：2018-04-27 08:11

本文选题：钢筋混凝土侧煤仓结构 + 抗震性能　；参考：《西安建筑科技大学》2015年硕士论文

【摘要】：火电厂钢筋混凝土侧煤仓结构是一种新的结构形式,与钢结构侧煤仓结构相比,该结构体系中的钢筋混凝土能够为结构自身提供较大的抗侧刚度,大幅降低工程总造价,具有较好的应用前景。但由于其上部刚度增大,造成结构上下刚度比过大,其地震响应有可能较钢结构侧煤仓结构体系更加明显,因此,有必要开展钢筋混凝土侧煤仓结构体系抗震性能的研究。鉴于该类结构体系的特殊性及复杂性,有必要采用弹塑性时程分析方法对其抗震性能开展精细化研究。本文以某火电厂钢筋混凝土侧煤仓结构为工程背景,采用弹塑性时程分析方法分析结构的地震反应,主要工作包括以下几方面:(1)基于ABAQUS有限元分析软件,选用实体单元和杆单元分别模拟结构中的梁、柱以及剪力墙中的混凝土和钢筋,并对混凝土的本构选用塑性损伤模型;为了减小计算机的工作量同时满足工程精度要求,将楼板的荷载以质量点的方式耦合到相应的梁上,从而建立钢筋混凝土侧煤仓结构的空间精细化分析模型。(2)将分析模型的周期与PKPM模型的周期进行对比,结果比较吻合;对结构模型的动力特性分析表明,结构中体型收进及剪力墙的偏心布置等引起结构低阶振型的平动和扭转耦合作用明显。(3)选用有代表性的加速度时程曲线对分析模型进行不同地震作用下的弹塑性时程分析,根据能量响应结果初步评估结构的弹塑性响应;对分析模型的精细化分析结果表明,罕遇地震作用下结构的基底剪力、弹塑性层间位移角等满足相关规范要求;为了判断出结构真正的薄弱部位,根据El-Centro波作用后结构构件中混凝土的受压损伤、受拉损伤及钢筋的塑性变形等参数分析其损伤程度,分析结果表明,第1层为结构的薄弱层。(4)本文最后就此钢筋混凝土侧煤仓结构的优化提出以下几点建议:对结构的薄弱部位进行局部加强,如增大第1层梁、柱的截面尺寸;通过调整结构刚度,如减小剪力墙的尺寸等措施来减小结构上下刚度比。总之,对该类特殊结构应该采用空间结构模型对其抗震性能进行精细化分析,根据分析结果采取合理措施提高其抗震性能,同时,更应重视该类结构的抗震概念设计,采取合理的结构体系和构造措施,有效保障钢筋混凝土结构的抗震性能。
[Abstract]:The reinforced concrete side coal bunker structure in thermal power plant is a new structure form. Compared with the steel structure side coal bunker structure, the reinforced concrete in the structure system can provide the structure itself with greater lateral stiffness and greatly reduce the total project cost. It has good application prospect. However, due to the increase of upper stiffness, the ratio of upper and lower stiffness is too large, and the seismic response may be more obvious than that of steel side coal bunker structure system. Therefore, it is necessary to study the seismic behavior of reinforced concrete side coal bunker structure system. In view of the particularity and complexity of this kind of structural system, it is necessary to use elastoplastic time-history analysis method to study its seismic performance. In this paper, based on the reinforced concrete side coal bunker structure of a thermal power plant, the elastoplastic time-history analysis method is used to analyze the seismic response of the structure. The main work includes the following aspects: 1) based on ABAQUS finite element analysis software. The solid element and the bar element are used to simulate the concrete and steel bar in the beam, column and shear wall respectively, and the plastic damage model is used for the constitutive structure of the concrete, in order to reduce the workload of the computer and meet the requirements of engineering precision. The load of floor is coupled to the corresponding beam in the form of mass point, and then the spatial fine analysis model of reinforced concrete side coal bunker structure is established. (2) the period of the analysis model is compared with the period of PKPM model, and the results are in good agreement. The analysis of the dynamic characteristics of the structural model shows that, The coupling of translation and torsion of the low-order vibration modes of the structure caused by the shape intake and the eccentric arrangement of the shear wall is obvious. 3) the elastoplastic time-history analysis of the analysis model under different earthquake action is carried out by using the representative acceleration history curve. According to the energy response results, the elastoplastic response of the structure is preliminarily evaluated, and the detailed analysis results of the analytical model show that the base shear force and the elastic-plastic interstory displacement angle of the structure under rare earthquake can meet the requirements of the relevant codes. In order to determine the real weak part of the structure, the damage degree of concrete under compression, tensile damage and plastic deformation of steel bar is analyzed according to the parameters of El-Centro wave. The results show that, The first floor is the weak layer of the structure. (4) in the end of this paper, the following suggestions are put forward to optimize the structure of the reinforced concrete side coal bunker: the local strengthening of the weak part of the structure, such as increasing the cross-section size of the first story beam and column; The ratio of upper and lower stiffness of the structure is reduced by adjusting the stiffness of the structure, such as reducing the size of the shear wall. In a word, the spatial structure model should be used to analyze the seismic performance of the special structure, and reasonable measures should be taken to improve the seismic performance according to the results of the analysis. At the same time, more attention should be paid to the seismic conceptual design of this kind of structure. Reasonable structural system and structural measures are adopted to effectively guarantee the seismic performance of reinforced concrete structures.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU352.11;TU375

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