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, . 22, (495) 316-39-64, a.buslov@yandex.ru;
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390000,
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, . 26/53, alexandrabakulina@yandex.
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а
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//
. 2012.
№
4.
. 63—68.
А.S. Buslov, A.A. Bakulina
INFLUENCE OF A ROUND CAP ON THE BEARING CAPACITY OF A LATERALLY LOADED PILE
Foundations of laterally loaded single piles are widely used as part of power transmission lines, wind power stations, highway structures, etc. Ongoing pressure applied to a laterally loaded pile, particularly at the ground level, causes the soil deformation characterized by the bulging of the soil surface.
In the majority of cases, the deformation strength of a pile depends on the front-face soil resis-tance, Horizontal beams, ground caps or rigid plates are used to increase the pile resistance. An ef-fective method of pressure reduction contemplates the use of a rigid round cap at the front-face or upper level of the soil.
In this paper, the authors analyse the data to examine how a round cap installed at the ground level impacts the bearing capacity of a single pile.
This research based on the methodology developed by the authors demonstrates that a later-ally loaded pile, supported by a rigid cap at the ground level, is exposed to increased resistance due to the following factors, including the passive pressure along the cap side that creates an un-loading effect for a horizontally-loaded pile. The cap acts as a vertical soil rebuff creating an addi-tional resistance moment; the horizontal shear of the cap causes supplementary lateral resistance of a pile.
The following initial geometric and elastic material properties of the single pile are applied: to-tal length L = 5.0 meters (3.0 m above and 2.0 m below the ground surface); pile diameter d = 40 centimeters; circle plates of various diameters D = 60; 70; 80 and 100 cm and their thickness
Elastic properties of the soil are assumed to be constant at each point below the surface of the ground, they are listed below: bulk modulus of soil Es=20 MPa; Poisson's ratio μ=0,37; unit
Weight γ=18,5 kN/m3; cohesion c=0,05 MPa; angle of internal friction φ=20°.
The data has proven that cap-covered piles are substantially more economical (over 40 %) in terms of materials consumption rate if compared to constant cross-section piles (cap-free or broad-ening piles), all other factors being equal.
Key words: single pile footing, lateral load, rigid round cap, bearing capacity.
References
1. Normy proektirovaniya kontaktnoy seti [Overhead Contact System Design Standards]. 141-99. MPS RF. Moscow, 2001.
2. Matus N.Yu. K raschetu gorizontal'no nagruzhennoy svai-kolonny s nizkim
rostverkom-ogolovkom [About the Design of a Laterally Loaded Pile-Column with Deep Grid Pile Foundation]. OOO HT Project — Ukraina, Odessa, 8 p.
3. Buslov A.S., Tulakov E.S. Raschet gorizontal'no nagruzhennykh odnostoechnykh opor po ustoy-chivosti [Stability Design of Laterally Loaded Single Footings]. Osnovaniya, fundamenty i mekhanika gruntov [Beddings, Foundations, and Soil Mechanics]. Moscow, 2004, no. 3, pp. 6—9.
A b o u t t h e a u t h o r s : Buslov Anatoliy Semenovich, Moscow State Open University named after V.S. Chernomyrdin, 22 Pavla Karchagina St., Moscow, 129626, Russian Federation; a.buslov@yandex.ru; 8 (495) 316-39-64;
Bakulina Aleksandra Aleksandrovna, Ryazan’ Branch,Moscow State Open University named after V.S. Chernomyrdin; 26/53 Pravo-Lybedskaya St., 390000, Ryazan’, Russian Federation; alexan-drabakulina@yandex.ru.
