Study of marine hydraulic structures under seismic effects

Abstract

Abstract A new era of development in the oil and gas sector of Azerbaijan, started from the moment of signing a contract with the world's leading oil companies, predetermines the intensive design and construction of new and modernization of existing oilfield facilities. The development of new oil and gas fields at great depths (Н≥500m) is largely associated with the construction of flexible hydraulic structures, one of the main features of which is their affiliation with flexible structures, which determines the need for dynamic calculations when designing for the joint effects of seismic, taking into account the load from waves, wind, currents. On the other hand, it is known that the Caspian region is a seismically active zone, which confirms the latest seismic disturbances with the epicenter in the Caspian Sea. This puts more stringent and high requirements for the calculation of seismic resistance and seismic resistance of such important, and one might say, strategic objects as offshore fixed platforms. Thus, it is possible to determine the seismic stresses for a given movement for each block support, taking into account the physical and mechanical properties of the soil and the depth of the foundation. During the study, earthquakes that occurred in the region were analyzed and their accelerograms were used as input data. The applied analytical methods in solving boundary value problems and the numerical implementation of analytical solutions give accurate results. On the basis of the conducted research and in-depth analysis of the data, the following were determined: the influence of the deck load on seismic stability; the internal forces of multi-tiered structures with various elements of diaphragms were calculated; calculation models of platforms were selected, both for the drilling phase and for the production phase; the dynamic characteristics of deep-water platforms in the vertical direction were modeled; seismic load distributions in elements of offshore platforms are calculated; computer programs have been developed for calculating the support block.