On ductile rupture criteria for structural tear in the case of ship collision and grounding

Estimation of failure strain of EH36 high strength marine structural steel using average stress triaxiality

“…Using the deviatoric strain tensor, the von Mises equivalent strain ε eq can be defined using the deviatoric strain tensor as shown in Eq. (6). By subtracting the elastic strain from the total von Mises equivalent strain, the von Mises equivalent plastic strain ε p.eq can be obtained.…”

“…By examining trends in the marine industry, Lehmann and Yu [6] proposed a new fracture criterion called the rupture index. The rupture index is based on continuum damage mechanics (CDM) theory.…”

Failure strain formulation via average stress triaxiality of an EH36 high strength steel

“…Hancock and Mackenzie (1976) proved how the stress triaxility has an effect on the failure via tests of tensile specimens with a series of notches. Lehmann and Yu (1998) suggested a rupture index governed by the stress triaxility using continuum damage mechanics (CDM) wherein damage growth is defined as the function of stress triaxility. In the failure criteria of RTCL (Rice-Tracey and Cockcroft-Latham) presented by Urban (2003) and Törnqvist (2003), it was assumed that the growth of stress triaxility governs the failure of material under the tensile condition.…”

A review-analysis on material failure modeling in ship collision

“…For a low alloy carbon steel (St52-3 steel), the failure parameter was estimated to 0.7. Lehmann and Yu (1998) applied this failure criterion in the finite element modeling of the quasi static penetration test of stiffened double plate ship bottom, showing a good agreement with experimental results. Broekhuijsen (2003) also calibrated experimentally the rupture index of mild steel to model numerically the punching tests of 12 mm thick plates so giving a good prediction of failure when compared with experimental tests and demonstrating a good performance when material is subjected to various stresses states (ISSC, 2006).…”

“…A ductile failure criterion in naval structures that takes into account the triaxial state of stresses in fractured material was suggested by Lehmann and Yu (1998). It is based on the continuum damage mechanics and it adopts a rupture index I R as a critical damage parameter which governs material damage evolution until the rupture (Servis and Samuelides, 2006).…”