Papers abstract:

Offshore pipelines are frequently subjected to accidental impact loads, e.g., from anchors or trawl gear. A lot of parameters e including the pipe geometry, material properties, pipeline content, impact velocity, etc. e influence the course of such an impact. Some of these parameters have been studied quite extensively while others not so much. This study presents material and component tests on specimens taken from an X65 offshore pipeline. Empty pipes, as well as open and closed water-filled pipes, are impacted at different velocities. Results in terms of force-displacement curves are quite similar for the empty and open water-filled pipes, while the closed water-filled pipes react differently as a consequence of internal pressure build-up during impact. Computer simulations of the component tests are carried out using various numerical techniques for fluid discretization and for fluid-structure interaction. Numerical results are generally in good agreement with experimental observations and serve as a helpful aid when interpreting results.

Product Overview:
This tutorial introduces a practical simulation of an impact event on a water-filled steel pipe using Abaqus/Explicit, referencing geometry, material behavior, and findings from the ISI study. The model simplifies the scenario by using an open-ended pipe and SPH fluid modeling, allowing for efficient simulation of water behavior. Key simulation steps include:

• Modeling pipe, water, rigid impactor, and supports using revolved and extruded sketches.
• Assigning Johnson–Cook plasticity and EOS properties to materials.
• Applying SPH for fluid modeling and explicit element types for structure.
• Defining contact properties, boundary conditions, and velocity loads.
• Setting up dynamic explicit steps and running impact analysis.

In this tutorial, the dynamic impact of a rigid indenter onto an open-ended water-filled X65 steel pipe is simulated, according to data from the work of Kristoffersen et al., 2014.