PSI - Issue 27

Aditya Rio Prabowo et al. / Procedia Structural Integrity 27 (2020) 171–178 Prabowo et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Table 2. Configuration of the struck vessel. Dimensions

Value 85.92 78.00 15.00

Length over all (m)

Length between perpendicular (m)

Breadth moulded (m)

Design draft (m)

4.30

Depth (m)

10.40

Frame spacing (m)

0.60

During the risk analysis, collision frequencies are determined, and limitations are recognized in the damage estimates using traditional approaches. The interested parties want to have a better understanding of collision resistance accounting for different striking vessels, various collision speed and angles, different structural arrangements, and different failure criteria. These requirements effectively drove the analysis of the consequences of applying the detailed finite element analysis (FEA) for calculating structural damage.

Table 3. Material properties for numerical simulation. Properties

Material Class Low-carbon steel

Medium-carbon steel

Alloy Steel

Density (kg/m 3 )

7865

7850

7850

Young’s modulus (MPa)

200,000

210,000

200,000

Poisson’s ratio

0.27 310 440

0.30 440 525

0.29 315 585

Yield strength (MPa) Ultimate strength (MPa)

Fig. 2 . Illustration of target point’s location on the struck vessel.

The results of these simulations depend on two main factors, namely the longitudinal location of the target points in each region and the implemented material type on the struck vessel. These factors, together with the striking bow shape and the assumption of perpendicular collision angle, identify the collision scenarios to be investigated in this section. The location of the target points is presented in Fig. 2. Four different collision cases based on different collision regions and the longitudinal position of target points together with three collision cases depending on material type are accounted into nonlinear finite element analyses. The velocity of the striking vessel is 6.17 m/sec, and the total simulation time is 0.567 sec. In the virtual simulation process, the struck ship will be considered as a deformable