海洋纤维增强复合柔性管拉伸性能

Tensile properties of marine fiber reinforced composite flexible pipes

纤维增强复合材料柔性管取代传统的碳素钢管是海洋油气选管的趋势。以热塑性纤维缠绕复合材料柔性管(RTPs)为研究对象,将弹塑性材料的本构关系与应力连续条件相结合,建立拉伸作用下任意增强层数RTPs的力学模型。在此基础上分析缠绕角、纤维增强层纤维含量、泊松比等参数对RTPs拉伸性能的影响,并开展拉伸试验进行验证。结果表明:纤维增强层的缠绕角是影响RTPs拉伸性能的主要因素,缠绕角度的降低显著提高了RTPs的纵向强度,缠绕角度小于±45°时纵向强度较高;增加纤维含量不能有效提高RTPs在有效应变范围内的整体抗拉强度,泊松比对RTPs的整体拉伸性能影响并不明显,试验结果与数值模拟结果吻合较好。

Replacement of composite flexible pipes made of fiber-reinforced composites instead of traditional carbon steel pipes is the trend of offshore oil and gas selection.A study on the tensile properties of reinforced thermoplastic pipes(RTPs)was presented.A mechanical model of RTPs with an arbitrary number of reinforced layers in tension was constructed by combining the constitutive relationship of elastoplastic materials with the stress continuity condition.On this basis,the effects of various parameters such as the winding angle,the fiber content of structurally reinforced layers,and the Poisson's ratio on the tensile properties of the RTPs were analyzed,and then a tensile test was carried out for validation.The results show that the winding angle of the structurally reinforced layers is the main factor affecting an RTP's tensile performance,where the decrease of the winding angle significantly improves the longitudinal strength.The winding angle which is less than±45°results in a higher strength in the longitudinal direction.In addition,the increase of the fiber content of structurally reinforced layers cannot effectively improve the overall tensile strength of RTPs within the effective strain range.The Poisson's ratio has little effect on the overall tensile properties of the RTPs.The experimental results are in good agreement with the numerical simulation results.