摘要
针对大口径煤气管道由于支架地基严重沉降而引起的自内力和强度安全问题,进行有限元模拟、强度评定和沉降规律研究。计算实际支架相对沉降导致的管道变形和应力分布,基于塑性失效等安全裕度准则,对应力进行分类强度评定。通过试探加载法,估算出中间支架单个鞍座的下拉载荷约等于管道自重的三倍。绘出管道底部典型位置的最大当量应力随中间支架相对沉降量的变化曲线,结果显示各处当量应力对支架沉降的响应基本呈线性规律,表明支架沉降引起的管道自内力相当于比例加载。同时发现,应力越高的位置对支架沉降越敏感,即随相对沉降量的增加会变得更加危险(?)据此提出垫高鞍座和局部补强的改造措施并获得良好效果。
By using finite element simulation, the estimation of strength and the study of settlement law for a large-diameter gas pipe were performed, concerning with the strength safety problem induced by the relative settlement of its support frames. The deformation and stress state under the condition of actual settlement was detailed calculated and the estimation of strength was carried out by the method of stress classification assessment based on the plastic failure criteria. Using the method of testing load, the drop-dowu load of an individual saddle of middle support frame was calculated and it was found that this load is as big as three times of the pipe weight. Furthermore, the variation curves are plotted about the maximum equivalent stress in three specific locations at the bottom of the pipe versus the relative settlement displacement based on the calculation. The curves indicate that the internal force in the pipe caused by the settlement of the support frames is to be equivalent to the proportional loading, according to the linear variation of equivalent stress versus the settlement displacement. It is also found that the position of higher stress is more sensitive to settlement, and it becomes more dangerous with the increment of support frames settlement. Based on the above analysis, improving advices, which had been proved to be with good effect, were proposed, including to raise the saddle and to partially reinforce the pipe.
出处
《化工设备与管道》
CAS
2010年第6期55-63,共9页
Process Equipment & Piping
关键词
大口径管道
支架沉降
强度评定
有限元法
large-diameter pipe
settlement of support frame
strength estimation
finite element method
