Impact of sea waves on underwater fish-breeding cages

• Main Authors: Pilyaev Sergey Ivanovich, Gubina Nadezhda Andreevna
• Format: Article
• Language: English
• Published: Moscow State University of Civil Engineering (MGSU) 2014-02-01
• Series: Vestnik MGSU
• Subjects: mariculture; fishes culture; underwater fishing cages; hydrobiotechnical constructions
• Online Access: http://vestnikmgsu.ru/files/archive/issues/2014/2/ru/20.pdf

Cultivation of sea objects is of great importance while solving the problems of providing the constantly growing requirements of the national economy with sea products. Cultivation of sea objects uses special hydrobiotechnical constructions. As the practice showed, cultivation of seafood is commercially impossible without solving the questions of calculating and designing such constructions. In special literature these questions are poorly covered or not considered at all. In the article the results of theoretical and pilot studies of waves influence on hydrobiotechnical constructions is provided, in particular on underwater fish-breeding cages.This article offers the theoretical solution to the problem of determining the efforts of the ropes holding the fish tank under wave influences. In order to solve this problem, the equations of hard drives movements were set up and the differential equations of free oscillations of buzz were obtained.When determining the horizontal movements, the four different configurations of connections and the system motion directions in general are possible in case of waveoscillations. Next step is the solution of the differential equations and determination of natural oscillation frequency in the direction of the vertical axis. Defining efforts in the ropes from their own weight (static calculation) is self-explanatory, it should be noted that accounting for the weighing influence of water on such structures does not have significant influence.Further the authors defined loading and efforts from the regular waves’ impacts.Modeling of the waves influence on submersible fish tank was carried by Fraud method. The studies were conducted with two models with large and small mesh. The signals of strain gauge sensors were registered by electronic measuring equipment.When comparing the theoretical and experimental data, satisfactory results have been obtained. It was determined that in order to improve the calculation methods it is appropriate to carry out an additional series of experiments for the refinement of the permeability coefficient, which is included in the calculation of the wave load.