Deadweight anchoring behavior for aquaculture longline
Author
Trujillo, Ernesto
León, Luis
Martínez, Guillermo
Full text
http://lajar.ucv.cl/index.php/rlajar/article/view/vol48-issue4-fulltext-232710.3856/vol48-issue4-fulltext-2327
Abstract
The similarity theory was used to study the behavior of five anchoring and one "rezon" type deadweight designs, using scale models. The surface sediments extracted from Charagato Bay, Cubagua Island, were characterized to evaluate the efficiency of these models on these substrates. A test structure consisting of a tank with a mixture of sediment and seawater, and a metal trestle was used. Tension variables were considered, using a 6 mm PE end section. Weights were added at one of its ends which represented the longline system's resistance force and at the other the model's force in the eyebolt (Tc) representing the gripping force due to the interaction of the anchoring design with the substrate, and the static rupture tension (Tr) upon the weight (Pm) of each model, against different anchoring attack angles (), aspect ratios (AR) 1/2.5; 1/3.0; 1/3.5, and 1/4.0; sail attack angles () of 0, 10, and 20°, and the efficiency index (EI) of each model. The Kruskal-Wallis contrast was used to detect the possible differences against different anchoring attack angles, and, to locate the differences between them; box and mustache graphs were used. The most effective model on very fine sand-type sediment was the pyramidal with the claw-like frame, followed by the pyramidal with the shovel-like frame and the "rezon" type traditionally used on Margarita Island.