Effects of Collision Damage on the Ultimate Strength of FPSO Vessels

Authors

Muhammad Zubair Muis Alie, Faculty of Engineering, Department of Ocean Engineering, Universitas Hasanuddin, Makassar 90245, IndonesiaFollow
Dian Ramasari, Faculty of Engineering, Department of Ocean Engineering, Universitas Hasanuddin, Makassar 90245, Indonesia
Taufiqur Rachman, Faculty of Engineering, Department of Ocean Engineering, Universitas Hasanuddin, Makassar 90245, Indonesia
Ristiyanto Adiputra, Faculty of Engineering, Kyushu University, Fukuoka, 819-0395, Jepang

Abstract

Floating production storage offloading (FPSO) vessels are movable offshore structures. These structures are designed with large dimensions, and their decks are loaded with several types of equipment. During collision damage, the hull and deck parts loaded with equipment are severely affected. Therefore, the ultimate strength of FPSO vessels should be thoroughly checked and evaluated. The objective of the present study is to analyze the ultimate strength of FPSO vessels against collision damage characterized by hogging and sagging under longitudinal bending. The cross section of an FPSO vessel is modeled with elements composed of stiffened and unstiffened plates. The vessel length is assumed to occupy one frame space. The ultimate strength of FPSO vessels against collision damage is determined by performing a numerical analysis under hogging and sagging conditions. Multipoint constraint is applied to both sides of the cross section, and the material properties are set to be constant. Collision damage is represented by the loss of element stiffness, and it represents the percentage of the ship’s depth. For the extent of transversal damage, B/16 is set to be constant. The minimum and maximum collision damages are taken as 10% and 60% of the ship’s depth, respectively. Numerical results show that the ultimate strength of FPSO vessels and their bending stiffness decrease under collision.

Bahasa Abstract

Pengaruh Kerusakan Tubrukan terhadap Kekuatan Kapal FPSO. FPSO adalah floating production storage offloading, salah satu struktur offshore dengan karakteristik bergerak. Struktur tersebut didesain dengan dimensi besar yang terdiri dari banyak peralatan di geladak. Ketika tubrukan terjadi, lambung kapal tidak hanya menerima dampaknya, tetapi juga geladak dimana banyak peralatan di tempatkan pada daerah tersebut. Oleh karena itu, kejadian ini harus diperiksa dan dievaluasi untuk kekuatan kapal. Tujuan dari penelitian ini adalah untuk menganalisis kekuatan kapal FPSO yang disebabkan oleh kerusakan tubrukan pada kondisi hogging dan sagging dalam arah membujur. Penampang kapal FPSO dimodelkan dengan memilki elemen yang terdiri dari pelat dan pelat berpenegar. Panjang kapal diasumsikan dengan satu jarak gading. Kekuatan kapal FPSO yang disebabkan oleh tubrukan dianalisis dengan menggunakan analisis numerik pada kondisi hogging dan sagging. MPC dtempatkan pada kedua sisi penampang kapal dan properti material dibuat konstan. Kerusakan tubrukan digambarkan oleh hilangnya kekakuan elemen dan merepresentasikan persentasi dari tinggi kapal. Pada arah melintang bagian geladak kapal, kerusakan tubrukan diambil B/16. Kerusakan tubrukan diambil 10% dan 60% untuk nilai minimum dan maksimum dari tinggi kapal secara berturut-turut. Hasil diperoleh bahwa kekuatan kapal yang disebabkan oleh kerusakan tubrukan dengan solusi numerik berkurang termasuk kekakuan lenturnya.

References

1. S. Zhang, R. Villavicencio, L. Zhu, P.T. Pedersen, Mar. Struct. 63 (2019) 239.
2. M.Z.M. Alie, Makara J. Technol. 20 (2016) 7.
3. J. Parunov, S. Rudan, B.B. Primorac, Eng. Struct. 148 (2017) 704.
4. M.Z.M. Alie, Int. J. Offshore Polar Eng. 28 (2018) 200.
5. B. Liu, R. Villavicencio, C.G. Soares, Mar. Struct. 40 (2015) 267.
6. B. Liu, R. Villavicencio, S. Zhang, C.G. Soares, Ocean Eng. 141 (2017) 326.
7. A. Campanile, V. Piscopo, A. Scamardella, Mar. Struct. 58 (2018) 321.
8. A. Campanile, V. Piscopo, A. Scamardella, Ocean Eng. 130 (2017) 371.
9. M.Z.M. Alie, S.I. Latumahina, Int. J. Technol. 10 (2019) 1065.
10. X. Li, W. Tang, Ocean Eng. 171 (2019) 332.
11. J.M. Underwood, A.J. Sobey, J.I.R Blake, R.A. Shenoi, Thin-Walled Struct. 106 (2016) 346.
12. A. Prestileo, E. Rizzuto, A.P. Teixeira, S.G. Soares, Mar. Struct. 33 (2013) 33.
13. D. Saydam, D.M. Frangopol, Ocean Eng. 68 (2013) 65.
14. M.Z.M. Alie, G. Sitepu, J. Sade, W. Mustafa, A.M. Nugraha, A.B.M. Saleh, ASME. OMAE201654041 (2016) V003T02A083.
15. Z. Gao, Z. Hu, G. Wang, Z. Jiang, Ocean Eng. 87 (2014) 121.

Recommended Citation

Alie, Muhammad Zubair Muis; Ramasari, Dian; Rachman, Taufiqur; and Adiputra, Ristiyanto (2020) "Effects of Collision Damage on the Ultimate Strength of FPSO Vessels," Makara Journal of Technology: Vol. 24: Iss. 1, Article 1.
DOI: 10.7454/mst.v24i1.3732
Available at: https://scholarhub.ui.ac.id/mjt/vol24/iss1/1