As an archipelago country that has the longest beach in the world, Indonesia requires a lot of breakwaters (including groin and revetment) not only to protect coasts from scouring but also to keep water in port basins still enough for ship maneuvers and loading-unloading operations. However, up till now in Indonesia,many constructions of breakwater and revetment do not consider coastal engineering and management carefully. There were many breakwaters, groins and revetment built to protect critical beaches, but the design and construction methods were unprofessional so that they did not last long. The closest example is coast of Tanjung Bunga, Makassar. Some groins built on Akkarena beach, were destroyed only after several years. A breakwater built using concrete cylinders, collapsed before it was finished. The cause of the scarcity of building breakwaters are high cost required due to the difficulty of work at sea and the amount of material needed. This study will look for a way out in the form of composite breakwaters by concrete piles, rubble-mound and box-beams. It is known that rubble-mound breakwaters are the most effective for absorbing wave energy, and even if broken they still can function; with light repair to the damage, they will return to even better functioning. The main problem is material required for a rubble-mound breakwater is so much and some shall be in great size. This material is usually obtained from blasting rocky mountain of good quality rock, which is now difficult to do because of environmental issues. By vertical breakwaters, the size and amount of stone required will be much reduced.
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