考虑边界土体性质悬跨管道振动特性分析

海底管道是海洋油气传输的生命线,其悬跨段的固有频率是决定动力响应状态的关键.建立了考虑边界土体性质的悬跨管道计算模型,通过土弹簧动刚度的变化描述海床土性质的变异.在此基础上进行悬跨管道的固有振动特性分析,分别讨论了边界土体性质、外部环境荷载、管道轴向力以及悬跨长度等变化对管道固有频率的影响.结果显示:跨长对管道固有频率影响最为明显,且对于不同的影响因素,悬跨管道的频率呈现不同的变化特征.

Analysis of vibration characteristics of free span pipeline considering boundary soil property

Submarine pipelines are regarded as the lifeline of sub-sea oil and gas transmission, and natural frequency of free span is a key factor for evaluating its dynamic response condition. Soil property which is used to establish analytical model of free span pipeline can be simulated by means of altering dynamic stiffness of soil spring. Based on the proposed model, the fundamental vibration characteristics are studied. The effects of various factors, such as soil property, external environmental load, axial force and span length on natural frequencies are discussed in detail. The results show that span length has the largest effect on natural frequencies and the frequencies have different features corresponding to different factors.