大型干式煤气柜的结构动力特性解析

煤气柜是煤气输送管网中被广泛应用的一种储气设备,其空间结构一般为高耸薄壁结构,对于地震及强风等动荷载较为敏感。为了保证煤气柜的安全,需对其进行抗震、抗风设计,而其前提则是必须了解煤气柜的结构动力特性。为此,应用现场实测和有限元分析方法对某300 000 m~3大型圆筒干式煤气柜的动力特性进行了研究。首先,在自然环境激励下进行了煤气柜加速度响应的现场实测,并对煤气柜的结构进行了动力特性参数识别,得到煤气柜活塞位于3/8柜体高度工况下的结构动力特性参数。其次,考虑到煤气柜柜体与柜顶的不同连接形式,建立了两种有限元分析模型,即有盖模型和无盖模型,分别对煤气柜结构动力特性参数进行了计算与分析。最后,将两种有限元模型计算得到的结果与现场实测结果进行了对比分析。结果表明,应用无盖模型计算得到的结构动力特性与现场实测结果更为吻合。该研究成果可为类似结构煤气柜的抗震、抗风设计提供参考。

Dynamic characteristics of a large-scale dry-type gas holder

A gas holder is widely used in gas pipeline network for storing gas, and spatially it is a thin-wall towering structure, which is very sensitive to dynamic loads, such as earthquake and strong wind. For security, earthquake and gale resistance design should be carried out on gas holders. As the precondition, it is necessary to know about the structural dynamic characteristics of gas holders. In this paper, field measurement and finite element analysis were conducted to identify the dynamic characteristics of a large-scale cylindrical dry-type gas holder with a volume of about 300 000 m³. First, the acceleration response of a gas holder was measured under the stimulation of natural environment, and dynamic characteristic parameters were identified on the structures of the gas holder. The parameters were obtained for the working conditions with gas holder piston located at three eighths of the total height. Second, two finite element models (with and without cover) were established for different connecting modes between its main body and the top, and used to calculate and analyze the dynamic characteristic parameters of the gas holder. Finally, comparative analysis was carried out between the finite element simulation results and field measurements. Results show that the dynamic characteristics obtained from the model without cover was more accordant with field measurements. The research results in this paper can act as a reference for the gas holder with similar structure in terms of seismic design and wind resistance design.