Perpustakaan Digital ITB

The growing implementation of carbon capture, utilization, and storage (CCUS) has increased the need for safe and reliable carbon dioxide (CO?) transportation through high pressure pipelines. One major safety concern is long-running fracture, in which an initiated crack continues to propagate along the pipeline due to the sustained crack-driving force generated by internal pressure and CO? decompression. This study determines the minimum thickness of a carbon fibre reinforced polymer (CFRP) crack arrestor required to stop crack propagation in an API 5L X52 pipeline. Crack propagation was simulated numerically using the Extended Finite Element Method (XFEM) in Abaqus 2024. The model consisted of a three dimensional pipeline containing an initial 30 mm longitudinal through wall crack and subjected to an internal pressure of 8 MPa. Model accuracy was evaluated through mesh convergence and analytical validation using the Mode I stress intensity factor and reference stress. The CFRP arrestor was modelled as an external layered reinforcement with a [0/90] fibre orientation and thicknesses of 5.010, 5.845, 6.680, 7.515, and 10.020 mm. Arrest performance was evaluated based on the final crack length, crack velocity, and whether the crack remained within the reinforced region. The results showed that the 5.010 mm arrestor was unable to stop the crack, whereas all configurations with thicknesses of 5.845 mm and above successfully arrested crack propagation. The minimum successful thickness was therefore determined to be 5.845 mm, corresponding to 35 composite plies and a final fully opened crack length of 65 mm. Increasing the arrestor thickness improved its performance, with the 10.020 mm configuration producing the shortest final crack length of 59 mm. These findings demonstrate that increasing CFRP thickness enhances local stiffness, reduces crack-tip deformation, and limits the distance of crack propagation in API 5L X52 CO? pipelines.