摘要
涡激振动会引起海底管跨的疲劳失效,激振频率、固有频率及激振载荷等是其主要影响因素。固有频率是表征结构对荷载敏感程度的指标,管跨共振只可能在漩涡发放主频率接近管土结构的固有频率时才产生。分析了海底土壤力学特性、悬跨长度、管道尺寸、海流速度等对管跨涡激振动的影响规律,结果表明:随着管道覆盖层土壤硬度增大,管跨的最大应力部位逐渐从管跨中点向土壤和管跨的交界区域移动;当海流速度较大时,对于小管径海底管道,靠近管跨中点和管跨两端易发生疲劳失效。在工程设计校核过程中对易引发疲劳失效的部位予以关注,有助于提高海底管道的可靠性。
Vortex induced vibration can cause fatigue failure of submarine pipeline span, and the vibration frequency, natural frequency and vibration load are the main influencing factors. The natural frequency is the index to characterize the sensitive degree of structure to the load, and the pipeline span resonance can occur only when the vortex main issuing frequency is close to the natural frequency of pipe-soil structure. This paper analyzes the influence law of the mechanics properties of subsea soil, span length, pipe size, current velocity on vortex induced vibration of submarine pipeline spans, and the results show that with the increase of hardness of pipeline covering layer, the maximum stress location of a pipeline span gradually moves from the midpoint of the span to the interfacing area between the soil and the pipeline span. When the current velocity is greater, the fatigue failure easily occurs close to the midpoint of the span and two ends of the span for small diameter submarine pipelines, paying attention to the locations where fatigue failures easily occur in engineering design and verification process can help to improve the reliability of submarine pipelines. （3 Tables, 4 Figures, 7 References）
出处
《油气储运》
CAS
2013年第1期8-11,共4页
Oil & Gas Storage and Transportation
关键词
管跨
固有频率
涡激振动
疲劳失效
敏感性
pipeline span, natural frequency, vortex induced vibration, fatigue failure, sensitivity
