The article is devoted to the problem of the scope of surveys to be carried out when inspecting construction sites of large-size steel tanks, which are composed of poorly bearing inhomogeneous soils. The information on tank accidents with oil product leakage and the main causes of such accidents is provided. It is shown that non-design loads caused by the process of uneven settling of the tank structure create zones of increased stresses and development of inadmissible deformations, which is the main cause of accidents at oil and oil products storage facilities. The reasons for the appearance of inhomogeneity zones are discussed. It is shown that the main cause may be erroneously planned and performed engineering surveys. The requirements of domestic and foreign regulations in terms of assigning the scope of survey works at the construction sites of large-sized vertical steel tanks have been analyzed. The geometrical approach to determination of probability of survey borehole hitting the inhomogeneity zone having a random location inside the contour of the tank was used. The generalization of previously performed calculations using the finite element method has been carried out and dependences of the acting equivalent stresses on the value of the vertical component of the non-uniform settlement of the central part of the bottom have been obtained. The dependence of the probability of getting a well (wells) into the inhomogeneity zone on the value of the radius of the zone of inhomogeneity for tanks of the most widespread standard sizes of tank is plotted. Conceptual approaches and ways to completely exclude the probability of development of local heterogeneity zones are proposed. One of them is based on application of multiview georadiotomography technology – scanning of continuous media by an antenna array with distributed receiving and transmitting high-frequency antennas of a wide range.
References
1. Chepur P.V., Napryazhenno-deformirovannoe sostoyanie rezervuara pri razvitii neravnomernykh osadok ego osnovaniya (Stress-strain state of the tank in the development of non-uniform drafts of its foundation): thesis of candidate of technical science, Moscow, 2015.
2. Tarasenko A.A., Gruchenkova A.A., Tarasenko M.A., Analysis of differences in the requirements of national regulations and USA standards in the development of the tank bottom differential subsidence (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 8, pp. 132-135.
3. Rukovodstvo po bezopasnosti vertikal'nykh tsilindricheskikh stal'nykh rezervuarov dlya nefti i nefteproduktov (Guide to the safety of vertical cylindrical steel tanks for oil and petroleum products), Moscow: Publ. of NTTs PB, 2013, 240 p.
4. Gruchenkova A.A., Napryazhenno-deformirovannoe sostoyanie rezervuarov pri lokal'noy neodnorodnosti gruntovogo osnovaniya (Stress-strain state of reservoirs with local inhomogeneity of the soil base): thesis of candidate of technical science, Tyumen, 2020.
5. Spravochnik geotekhnika. Osnovaniya, fundamenty i podzemnye sooruzheniya (Handbook of geotechnician. Subfoundation, foundations and underground structures): edited by Il'ichev V.A., Mangushev R.A., Moscow: ASV Publ., 2014, 728 p.
6. Romanov D.B., Zykov A.A., Fedyanin I.S., Sukhobok Yu.A., Experimental investigations of a possibility of determining the physical and electrophysical properties of multilayer media using radiowave tomography (In Russ.), Izvestiya vuzov. Fizika = Russian Physics Journal, 2020, V. 63, no. 2(746), pp. 30-35, DOI: https://doi.org/10.17223/00213411/63/2/30
