- BASES AND FOUNDATIONS, UNDERGROUND STRUCTURES
- Providing the Durability of Hydrotechnical Piles Submerged by Compact Methods
- UDC 624.157
Anatoliy A. GONCHAROV, e-mail: goncharovaa@mgsu.ru
Moscow State University of Civil Engineering (National Research University), Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation
Abstract. The main factors of influence on the durability of piles immersed by impact methods and operated in contact with an aggressive environment are given. On the basis of the analysis of previous works on this issue and the conducted studies, the main activities that need to be carried out when designing and executing works for construction of pile foundations in the area of aggressive environment are formulated. The main condition for ensuring the integrity of piles when driving and the subsequent durability is to limit the dynamic stresses acting during installation. Modern hydraulic hammers make it possible to adjust the dynamic stresses within the specified admissible limits. To ensure that piles can be submerged at an increased value of the acting stresses, it is also necessary to increase the concrete strength class to a value not lower than B40. In this case, the pre-stress of the reinforcement should not exceed 0.23 of the prismatic strength of concrete. To prevent corrosion of reinforcement it is necessary to introduce additives-corrosion inhibitors into the concrete. When the pile comes into contact with a corrosive environment, waterproof coatings must be used during installation.
Key words: dynamic stresses, dynamic module of concrete elasticity, micro-destructions, boundaries of micro-cracks formation, shock pulse, healing of micro-defects, potentiometric measurements, depassivation of reinforcement. - REFERENCES
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