Reinforced thermoplastic pipes (RTP) are widely used in the offshore oil and gas production industry for their excellent flexibility, corrosion resistance and internal pressure resistance. RTPs inevitably experience extreme environmental loads including internal pressure and tensile load in the procedures of installation and operation, which influence the structural integrity and safety. Therefore, reinforced layers of RTP are designed to bear internal pressure and tensile load. Herein, the mechanical behavior of fiber-reinforced thermoplastic pipe that consisting of aramid fiber braid reinforced layers is investigated by combination of numerical simulation and experimental methods. The full-scale internal pressure bursting experiments of 1-inch aramid fiber RTPs were carried out to study the burst pressure and failure behavior. A finite element model of aramid fiber RTP is established using ABAQUS, which considers the material nonlinearities as well as frictional interactions between layers. Based on the finite element model which validated by the experimental results, the mechanical behavior of fiber reinforced thermoplastic pipe subjected to internal pressure and tensile load is investigated in detail. The current study compares the influence of braided angle of fiber-reinforced layers, friction coefficient between each layer and load conditions on the mechanical behavior of RTPs. The experiment results reveal that the bursting pressure of 1-inch aramid fiber RTPs is about 76.1 MPa. The failure of aramid fiber RTP under internal pressure is dictated by leakage due to the fracture of fiber-reinforced layers and the fracture of the internal layer at the end fitting. It is worth noting that the braiding angle renders an obvious influence on mechanical properties of fiber-reinforced RTPs, whereas the mechanical behavior remains insensitive to friction coefficient between layers. Moreover, the synergistic influence of internal pressure and tensile load significantly affects the mechanical behavior of fiber-reinforced RTPs. The current study shall serve as a reference for the design and application of fiber-reinforced thermoplastic pipes in marine oil and gas production.

增强热塑性管道（RTP）以其优异的柔韧性、耐腐蚀性和耐内压性被广泛应用于海上石油和天然气生产行业。RTP在安装和运行过程中不可避免地会承受包括内压和拉伸载荷在内的极端环境载荷，从而影响结构的完整性和安全性。因此，RTP 的增强层设计为承受内部压力和拉伸载荷。本文结合数值模拟和实验方法研究了由芳纶纤维编织增强层组成的纤维增强热塑性管道的力学行为。进行了1英寸芳纶纤维RTPs的全尺寸内压爆破实验，研究了爆破压力和破坏行为。使用ABAQUS建立芳纶纤维RTP有限元模型，该模型考虑了材料非线性以及层间摩擦相互作用。基于经实验验证的有限元模型，详细研究了纤维增强热塑性管在内压和拉伸载荷作用下的力学行为。目前的研究比较了纤维增强层的编织角度、每层之间的摩擦系数和负载条件对 RTP 机械性能的影响。实验结果表明，1英寸芳纶纤维RTP的爆破压力约为76.1 MPa。芳纶纤维 RTP 在内部压力下的失效是由纤维增强层断裂和端部接头处内层断裂导致的泄漏决定的。值得注意的是，编织角度对纤维增强 RTP 的机械性能有明显影响，而机械性能对层间摩擦系数不敏感。此外，内部压力和拉伸载荷的协同影响显着影响纤维增强 RTP 的机械性能。本研究可为纤维增强热塑性管道在海洋油气生产​​中的设计和应用提供参考。内部压力和拉伸载荷的协同影响显着影响纤维增强 RTP 的机械性能。本研究可为纤维增强热塑性管道在海洋油气生产​​中的设计和应用提供参考。内部压力和拉伸载荷的协同影响显着影响纤维增强 RTP 的机械性能。本研究可为纤维增强热塑性管道在海洋油气生产​​中的设计和应用提供参考。