A project of concrete stabilized spar buoy as a coastal environmental observation and maritime safety platform

Abstract

Feasibility study of a long-lived autonomous sea observatory on the basis of a stabilized spar buoy is presented. The buoy design is developed to sustain harsh weather and hydrodynamic conditions of near-shore of the North-Eastern Black Sea with expected life-time over 10\xa0years. It has the following dimensions: diameter of 2.4\xa0m, length of 45\xa0m, prestressed concrete bearing structure length of 33\xa0m, floating draft of 30\xa0m, 12\xa0m steel mast, dry weight of about 120\xa0tonnes. The buoy is equipped with mooring anchors and three submerged floatages for its stabilization and minimization of an observational noise during measurements. To perform design testing, elaborate technical requirements and adopt particular technological and logistical solutions numerical simulations are conducted. The strength and durability of the buoy are assessed primarily through a random response analysis of its stress-strain state under irregular wind-wave conditions with requirements of actual standards and codes also taken into consideration. Characteristics of near-shore environment, in particular, mean and extreme wind-wave conditions, are specified for a site of the Field Research Facility of the Southern Branch of the P.P. Shirshov Institute of Oceanology of Russian Academy of Sciences (the Gelendzhik Bay, Russia) using historical data and theoretical models of wind-wave growth in the near-shore. Low-cost concrete buoys of the proposed design can be used both as autonomous sea stations and as units of networks for marine studies and sea environment monitoring. Dynamical characteristics of the buoy ensure high-precision measurements and its applications in telecommunication, maritime safety, etc.