Subsea steel pipelines are often coated with external polymer coatings. While primarily applied for corrosion protection and thermal insulation, such coatings have been shown to contribute significantly to the energy absorption during impact events. However, due to the lack of reliable models accounting for the complex coating features, positive contributions from the coating to the mechanical response of the pipeline are often omitted in design. In a previous study, samples of a typical polymer coating were scanned using X-ray micro computed tomography (XRMCT) and the density mappings were applied to build finite element (FE) models of the porous morphology. These FE models were then used to calibrate a constitutive material model, which takes the porosity of the coating into account. It was concluded that the constitutive model may be applied in large-scale FE simulations of coated pipelines. In this work, the calibrated constitutive model is used to simulate the response of quasi-static indentation and impact tests performed on full-scale offshore pipeline components with and without multi-layered polymeric coating. The objectives of the work are to evaluate the performance of the originally presented model and to implement modifications essential in capturing the physical phenomena of the problem. The original model is seen to describe the early parts of the deformation very well. However, some deviations are seen as the coating becomes severely compressed between the indenter and the steel pipe. A strain- and porosity-based fracture criterion is therefore implemented, which alleviates the problem and produces a good correspondence between simulations and experiments. Modifications are also made to the coating model to include dependencies of strain-rate and temperature in the coating material response. The modified model is calibrated to strain-rate and temperature data retrieved from a similar polymer material found in the literature. Case studies with simulations of impact events under various strain-rate and temperature conditions are performed. The simulation results are compared to quasi-static indentation and impact tests presented in previous works. These results give indications that the strain-rate and thermal sensitivity of the coating material should be further explored.

海底钢质管道通常涂有外部聚合物涂层。虽然主要用于腐蚀防护和隔热，但已证明此类涂层在冲击事件期间对能量吸收有显着贡献。然而，由于缺乏可靠的模型来解释复杂的涂层特征，因此在设计中常常忽略了涂层对管道机械响应的积极贡献。在以前的研究中，使用X射线微计算机断层扫描（XRMCT）扫描了典型聚合物涂层的样品，并应用了密度图来建立多孔形态的有限元（FE）模型。然后将这些有限元模型用于校准本构材料模型，该模型考虑了涂层的孔隙率。结论是，本构模型可应​​用于涂层管道的大规模有限元模拟中。在这项工作中，使用校准后的本构模型来模拟准静态压痕的响应以及在有或没有多层聚合物涂层的情况下对满量程海上管道组件进行的冲击测试。这项工作的目的是评估最初提出的模型的性能，并对捕获问题的物理现象进行必要的修改。可以看到原始模型很好地描述了变形的早期部分。但是，随着涂层在压头和钢管之间被严重压缩，可以看到一些偏差。因此，实施了基于应变和孔隙率的断裂准则，这样可以缓解该问题，并在模拟和实验之间产生良好的对应关系。还对涂层模型进行了修改，以包括涂层材料响应中应变率和温度的依赖性。修改后的模型经过校准，可以从文献中发现的类似聚合物材料中检索出应变率和温度数据。进行了在各种应变率和温度条件下模拟冲击事件的案例研究。将模拟结果与先前工作中提出的准静态压痕和冲击测试进行了比较。这些结果表明应进一步探索涂层材料的应变率和热敏感性。还对涂层模型进行了修改，以包括涂层材料响应中应变率和温度的依赖性。修改后的模型经过校准，可以从文献中发现的类似聚合物材料中检索出应变率和温度数据。进行了在各种应变率和温度条件下模拟冲击事件的案例研究。将模拟结果与先前工作中提出的准静态压痕和冲击测试进行了比较。这些结果表明应进一步探索涂层材料的应变率和热敏感性。还对涂层模型进行了修改，以包括涂层材料响应中应变率和温度的依赖性。修改后的模型经过校准，可以从文献中发现的类似聚合物材料中检索出应变率和温度数据。进行了在各种应变率和温度条件下模拟冲击事件的案例研究。将模拟结果与先前工作中提出的准静态压痕和冲击测试进行了比较。这些结果表明应进一步探索涂层材料的应变率和热敏感性。进行了在各种应变率和温度条件下模拟冲击事件的案例研究。将模拟结果与先前工作中提出的准静态压痕和冲击测试进行了比较。这些结果表明应进一步探索涂层材料的应变率和热敏感性。进行了在各种应变率和温度条件下模拟冲击事件的案例研究。将模拟结果与先前工作中提出的准静态压痕和冲击测试进行了比较。这些结果表明应进一步探索涂层材料的应变率和热敏感性。