Perilaku Deformasi Pemecah Gelombang Kantong Pasir Tipe Tenggelam
Keywords:
Sandbag breakwater, Deformation, Dimension and Density of sandbags.Abstract
Abstract. Breakwater is one of coastal structures to overcome problems of abrasion. Due to difficulties in obtaining rock material at the coast area, so the using of sandbags as a breakwater providing advantages in utilizing local materials. Therefore, the problem of the rock material supply can be overcome. The environmentally oriented conservation of the coastal protection is necessarily built without damaging the beauty of the coast itself. That is why this research on behavior of the stability of submerged sandbag breakwater is carried out this experimental research conducted in 2-D physical model and take place on the flume tank of Laboratory Ocean Engineering Department, ITS Surabaya for stability test, it shows that the deformation of the sandbags is influenced by the elasticity of sandbags which depends on its dimension and density. The sandbags size influences the grip zone. As a result, the deformation of sandbag depends on the wave forces, as a consequence of the change of slope and cross areas due to sandbags shape and formation type. The formation of SK1 has relatively high stability; the structure with mild slope is more stable, and the sandbag shapes B1 more stable than B2Abstrak. Pemecah gelombang merupakan salah satu struktur pantai yang digunakan untuk mengatasi permasalahan abrasi. Namun sering sulit ditemukan material batuan di lokasi tersebut, maka penggunaan kantong pasir sebagai pemecah gelombang menguntung karena menggunakan material lokal. Sehingga permasalahan suplai material batuan dapat terselesaikan. Pengaman pantai yang berwawasan lingkungan sangat diperlukan untuk mengamankan pantai tanpa merusak pemandangan pantai. Oleh sebab itu penelitian ini melakukan studi mengenai perilaku stabilitas pemecah gelombang kantong pasir tipe tenggelam.Penelitian ini berbentuk pengujian model fisik 2-D skala lab, yang dilakukan di Flume Tank Laboratorium Jurusan Teknik Kelautan, ITS Surabaya. Pada uji stabilitas menunjukkan bahwa respon kantong pasir dipengaruhi oleh elastisitas kantong pasir, sedangkan elastisitas kantong pasir tergantung pada dimensi kantong dan kepadatan kantong. Ukuran kantong berpengaruh terhadap zona jepitan, dimana zona jepitan ini dipengaruhi oleh perbandingan panjang dan tebal kantong. Perilaku deformasi kantong pasir tergantung pada elastisitas kantong. Sesuai hasil pengujian, deformasi kantong pasir tergantung pada gaya yang bekerja pada kantong, jadi deformasi kantong dipengaruhi oleh kemiringan dan luas penampang kantong, sebagai akibat perubahan bentuk kantong dan jenis
susunan. Jenis susunan SK1 mempunyai stabilitas relatif tinggi; struktur dengan kemiringan landai lebih stabil, dan bentuk kantong B1 lebih stabil dibandingkan bentuk B2 untuk susunan yang sama.
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