Determination of Long-Term Strength of Frozen Soils and Bearing Capacity of Piles by Means of Cone Penetration Test

In the Russian Federation and abroad, great attention is traditionally paid to the development of field methods of soil testing, which is certainly a positive factor that contributes to improving the quality and efficiency of engineering and geological surveys. Unfortunately, in a number of articles published today, mostly by young authors, there is a general negative trend – their insufficient quality due to the lack of knowledge of the results of studies of domestic specialists carried out in previous years (sometimes completely ignored); insufficient understanding of basic terms and positions of soil mechanics, bases and foundations. On the example of one of such articles, in the context of the discussion on the issue addressed therein, analyse these shortcomings. Brief historical data on Cone Penetration Testing (CPT) of plastic-frozen soils with Relaxation-Creep Test (RCT) are given. The difference between CPT stabilization curves and long-term strength curves, Relaxation-Creep Test and laboratory dynamometric testing is shown. Based on the analysis, it was concluded that the authors of the article had a strange understanding of such key terms as “relaxation-creep test,” “relaxation test”, “stress relaxation”, “dynamometric method”, “pile ground base”, “unit long-term resistance of frozen soil under pile end”, “unit long-term resistance of frozen soil to shear along frozen surface of the pile”, “long-term compression strength”, “long-term shear strength”. Recommendations are given to authors to improve the quality of scientific articles. It is noted that when deciding to publish an article, it should always be remembered that any scientific article also performs an educational function – teaches and forms the level of the reader as a specialist.

I.B. RYZHKOV¹, Doctor of Sciences (Engineering), (This email address is being protected from spambots. You need JavaScript enabled to view it.);
M.A. MINKIN², Doctor of Sciences (Geology and Mineralogy), (This email address is being protected from spambots. You need JavaScript enabled to view it.);
O.N. ISAEV³, Doctor of Sciences (Engineering), (This email address is being protected from spambots. You need JavaScript enabled to view it.)

¹ GUP “Institute BashNIIstroy” (3, Konstitutsii Street, Ufa, 450064, Russian Federation)
² “Fundamentproekt” JSC (1, bldg. 1, Volokolamskoye Highway, Moscow, 125080, Russian Federation)
³ Research Institute of Bases and Underground Structures (NIIOSP) named after N.M. Gersevanov, Research Center of Construction JSC (59, Ryazanskiy Avenue, Moscow, 109428, Russian Federation)

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