以用于水下铺设的纤维缠绕增强复合管(RTP)为主要研究对象,考虑风浪流环境力作用及铺管平台运动等动态环境的影响,以及管道自身轴向拉力和弯曲的作用,采用悬链线理论方法及数值软件模拟计算方法,提出一套对大口径RTP的水下铺设设计的安全评估方法.对铺设的关键参数——材料属性、铺设角度、管线形态、端部张力、浮块重量、铺设深度等进行分析,研究RTP与浮式平台在环境力作用下运动及受力的非线性问题,以及大口径RTP轴向拉伸和弯曲剪切失效模式.结果表明:所提出的安全评估方法能够有效、真实地评估水下铺设过程中RTP的安全性能,能够为RTP安全评估提供符合工程实际的参考建议.
With the fiber-reinforced thermoplastic flexible pipe (RTP) used in underwater pipe-lay as the object of the research, considering the effects of wind, wave and current load and the motion of pipe-lay platforms as well as the axial tension and bending shear of RTP, a safety assessment method on the underwater pipe-lay design of the big RTP installation was given by using the catenary theory and hydrodynamic calculation method. The critical parameters of the RTP including material property, laid angle, pipeline shape, top tension, buoyant weight and laid depth were analyzed, the nonlinear problems of RTP and pipe-lay platform under the dynamic action of environmental loads were studied, and the failure modes of axial tension and bending shear of the big RTP were mastered. The results show that the theoretical guidance and failure analysis method can be used to assess the safety of RTP during the installation procedure under sea effectively and truly. Finally some reference advises of engineering practice for safety assessment were proposed.