Meshfree simulations of large scale ductile fracture of stiffened ship hull plates during ship stranding

In this work, we have developed a systematic computational methodology to directly simulate the ductile fracture of ship hull structure during ship stranding based on the meshfree Reproducing Kernel Particle Method. The whole computational algorithm has four parts: The first part is establishing interpolation shape functions of RKPM; the second part is the meshfree computational algorithm for simulation of three-dimensional crack propagation; The third part is a computational algorithm for detecting contact and calculating interaction force during ship stranding or grounding, and the last part is the constitutive modeling and update procedure during simulation for ship hull structure material. In this work, we adopt the Gurson-Tvergaard-Needleman model to model large scale ship hull structures. To validate above modeling and computational methodology, a large scale simulation of ship hull structure indentation test is carried out to directly comparing with the experimental test conducted by Alsos and Amdahl (Int J Impact Eng 36(6):799-807, 2009). The comparison between numerical results and experimental test results have been carefully analyzed. Subsequently, the simulations of simplified stranding processes in three different cases are performed. The results from numerical simulations indicate that the proposed computational algorithm is capable of capturing the plastic deformation and damage of ship hull structure subjected to grounding impact.