DETERMINATION OF THE BEARING CAPACITY OF A PILE-SCREW FOUNDATION IN A CRYOLITHOZONE

Abstract

The relevance of the study lies in the problem of calculating the bearing capacity of pile-screw foundations in the conditions of cryolithozone propagation under the influence of static pulling and pressing loads. Pile-screw foundations are a fairly new type in construction, although the first mention of them dates back to the late XVIII – early XIX centuries. This technology has proven itself from the best side. In recent years, screw piles have gained wide popularity in the construction of various facilities, but still occupy a relatively small share in foundation construction. The potential of this technology is poorly disclosed, the definition of load-bearing capacity in domestic standards is not regulated. Objective to analyze the existing methods and develop recommendations for calculating the bearing capacity of pile-screw foundations in cryolithozone conditions, comparing the results of calculations of the ultimate resistances of this type of foundation obtained by various methods with full-scale field tests and drilling piles. Methods: systematization, analysis of domestic and foreign experience in calculating screw piles in the areas of permafrost distribution; collection and processing of materials for field testing of soils with screw piles in the area of arrangement of the Bovanenkovskoe field; performing calculations of bearing capacity by various methods and comparing the results with data from field tests and drilling piles; description of the methodology for conducting field tests of piles in the conditions of the cryolithozone. Results. The authors have carried out the calculations of the bearing capacity of screw piles under cryolithozone conditions by various methods described in the literature and their comparison with the data of field tests of soils, a comparative assessment of the bearing capacity of screw piles with metal drill piles with a tip in the same geocryological conditions, revealed the advantages and disadvantages of the methods considered and various types of pile foundations. Based on the results obtained, conclusions are drawn about the possibility of using screw piles in cryolithozones and obtaining the necessary and sufficient information for their design.

Keywords

• pile-screw foundations
• cryolithozone
• full-scale field tests
• bearing capacity
• static loads
• settlement
• outlet
• lateral surface
• tip
• blade
• calculation methods
• comparative analysis
• permissible load
• soil temperature