Analisa Tegangan Mooring pada Floating Breakwater Tipe Gergaji dengan Pemodelan Fisik

https://doi.org/10.5614/jts.2021.28.3.6

Authors

  • Sujantoko Sujantoko Departemen Teknik Kelautan, Institut Teknologi Sepuluh Nopember
  • Eko Budi Djatmiko Departemen Teknik Kelautan, Institut Teknologi Sepuluh November
  • Wisnu Wardhana Departemen Teknik Kelautan, Institut Teknologi Sepuluh November
  • Aditya Hidayatullah Departemen Teknik Kelautan, Institut Teknologi Sepuluh November

Keywords:

Floating breakwater, model fisik, sudut mooring, tegangan mooring

Abstract

Abstrak

Floating breakwater dapat diaplikasikan sebagai alternatif dari fixed breakwater di perairan pantai dengan kondisi tertentu secara efisien dan efektif, desainnya dapat dielaborasi dengan fleksibel, dan instalasinya lebih mudah. Salah satu aspek dasar dalam desain floating breakwater adalah sistem mooring yang baik, sehingga struktur tersebut dapat berada pada posisinya dan kinerjanya meningkat. Penelitian ini bertujuan untuk menentukan besarnya tegangan mooring maksimum melalui eksperimen pada model floating breakwater tipe gergaji dan ponton. Model floating breakwater dibuat dari bahan polylactic acid dan model tali mooring digunakan jenis polyethylene. Pengujian fisik dilakukan dengan gelombang irreguler dan spektrum JONSWAP di wave flume. Selama pengujian dilakukan berbagai variasi input tinggi gelombang (Hs), periode gelombang (T), kedalaman air (d), dan sudut mooring (q). Hasil penelitian ini menunjukkan nilai tegangan mooring maksimum baik floating breakwater tipe gergaji dan ponton terjadi pada sudut mooring 30⁰ dan kedalaman air 45 cm secara berturut turut sebesar 5.28 N dan 4.91 N, sedangkan tegangan terkecil terjadi pada sudut mooring 60⁰ dan kedalaman air 41 cm yaitu 1,03 N dan 1,27 N. Perbandingan nilai tegangan mooring tipe gergaji pada sudut mooring (30o, 45o, 60o) adalah lebih besar 10.82%-19.71%, 24.00-40.94%, dan 22.2%-39.42% dari tipe ponton pada kedalaman air 41cm, 43cm dan 45cm.

Kata-kata kunci:  Floating breakwater, model fisik, sudut mooring, tegangan mooring.

Abstract

Floating breakwater can be applied as an alternative to the fixed breakwater in coastal waters with certain conditions efficiently and effectively, the design can be elaborated flexibly, and the installation is easier. One of the basic aspects in the design of a floating breakwater is a good mooring system so that the structure can be in position and its performance is increased. This study aims to determine the maximum mooring tension through experiments on the saw and pontoon-type floating breakwater models. The floating breakwater model is made of polylactic acid and the mooring rope model is made of polyethylene. Physical testing was carried out with irregular waves and the JONSWAP spectrum in the wave flume. During the test, various input variations of wave height (Hs), wave period (T), water depth (d), and mooring angle (q) were carried out. The results of this study indicate that the maximum mooring tension value for both saw and pontoon floating breakwater occurs at a mooring angle of 30⁰ and a water depth of 45 cm respectively 5.28 N and 4.91 N, while the smallest tension occurs at a mooring angle of 60⁰ and a water depth of 41 cm, namely 1 .03 N and 1.27 N. Comparison of saw-type mooring tension values ​​at mooring angles (30o, 45o, 60o) were 10.82%-1971%, 24.00-40.94%, and 22.2%-39.42% higher than the pontoon type at water depth 41cm, 43cm and 45cm.

Keywords:  Floating breakwater, physical model, mooring angle, mooring tension.

 

References

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Published

2022-01-04