RU2459041C2 - Aseismic pile - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: aseismic pile comprises a cylindrical fabricated structure made of reinforced concrete placed into a sand concrete hollow reinforced cylinder, on the bottom of which there is granite sand, with a layer of around one metre. The space between the reinforced cylindrical structure and the sand concrete reinforced cylinder is filled with sand for the height of the hollow cylinder.

EFFECT: invention provides for foundation reliability, reinforcement, preventing building damage in case of considerable earth oscillations under seismically dangerous conditions, lower material intensity.

1 dwg

Description

The present invention relates to the field of construction, in particular to devices used to strengthen the foundation of buildings and structures, to prevent their destruction, in seismically disadvantaged areas.

Known bored pile made of concrete and metal, which is installed in the well obtained by drilling to a considerable depth, to the rocky base (1-2).

The disadvantage of such a pile is its insignificant support area, as a result of which it is not a reliable strengthening of the building during tremors, since during movements in the base of the buildings reactions occur that can both destroy the pile and pull it out of the base.

In addition, this type of piles requires special costs, since a significant amount of concrete and metal is used in their production.

A floating pile is known, which is a structure in the form of a beam-like frame using metal wedges that are not fixed at a certain depth, but are, as it were, a “floating support” of a building that accepts the load, holds the foundation, preventing its destruction (3-4).

The production and installation of this design is an expensive and difficult to install procedure, it takes a significant amount of metal necessary for the manufacture of a metal frame in the form of wedges.

During earthquakes, the use of floating piles does not exclude the possibility of “tearing them out”, since such structures are not directly fixed anywhere, therefore, in terms of their shape and features, these installations cannot be a reliable means of strengthening the foundation of a building.

The objective of the invention is to strengthen the foundation of high-rise buildings, public buildings of large volume and number of storeys, structures in complex military facilities, the use of the proposed structure will prevent the destruction of buildings even with significant fluctuations of the earth in seismically dangerous areas.

The problem is solved by creating a seismically insulating pile, consisting of a reinforced concrete structure mounted on a sand cushion.

A seismic insulating pile is depicted in the drawing, where the positions indicated:

1 - reinforced concrete cylindrical structure;

2 - well;

3 - sand concrete hollow reinforced cylinder;

4 - granite sand.

A seismic insulating pile consists of a reinforced concrete cylindrical structure (1) installed in a sand-concrete hollow reinforced cylinder (3), on the bottom of which granite sand is poured (4).

Further technology for the manufacture and installation of seismic insulating piles is as follows.

Initially, a well (2) is drilled with a diameter of 1.8 m to 2 m, a depth of 10 to 12 m. The bottom and walls of the well (2) are reinforced with knitted frames, a casing is installed in the well (2), cavities between the drilled well (2) and coarse casing are concreted under pressure by a sand-blasting device with a cement-sand mass, the wall thickness of the well is calculated. The casing is removed.

As a result, a sand-concrete hollow reinforced cylinder (3) is formed. Granite sand (GOST 8736-93) (4) is poured at the bottom of the obtained cylinder (3) (layer height from 800 to 1000 mm (calculated).

In a sand-concrete hollow reinforced cylinder (3), a reinforced concrete cylindrical structure (1) with a clearance of 200 mm, made in the factory, made of reinforced concrete with special additives that increase the grade and water resistance of concrete, is installed on the formed “sand cushion”. An empty cavity (gap) between the obtained sand concrete reinforced hollow cylinder (3) and the reinforced concrete structure (1) is filled with granite sand (GOST 8736-93) (4) to the height of the hollow cylinder.

The proposed seismically insulating pile allows you to strengthen the foundation, to prevent the destruction of the building, even with significant fluctuations of the earth in seismically dangerous conditions.

Sand is an ideal material giving zero draft to a building. In the case of an earthquake, due to the special structure of the seismic insulating pile and the properties of granite sand, which has a compressive strength of more than 40 MPa, frost resistance (up to F200), water permeability (up to W-4), resistance to abrasion and aggressive environments, the proposed design will act as a giant the shock absorber, earth vibrations will be suppressed in the foundation of the building and the possibility of destruction will be minimized.

The estimated permissible pile drilling depth, calculated for a pile cut with a jerk of 8-9 points on the Richter scale, is from 10 ÷ 12 m (with an earthquake, there is a high probability of a pile cut that is set below the indicated mark).

Installation of seismic insulating piles is carried out at an optimally safe depth, which implies significant savings, since there is no need to drill a well to a greater depth (the base of the pile cone can be increased to the required diameter).

The use of the proposed seismic insulating piles does not require additional costs, since the maximum safety level of a building is achieved by using a significantly smaller number of piles compared to the most commonly used piles.

The use of the proposed seismic insulating piles to strengthen the foundation of buildings, mainly high-rise ones, is the most optimal, because in the event of an earthquake, the concrete structure will act as a giant shock absorber, preventing the destruction of the building and minimizing the devastating consequences.

Given the minimum level of costs during production and installation, reliability and a clear advantage over other types of piles, the use of this pile in seismically unfavorable areas is the most relevant.

Information sources

1. SNiP 2.02.03-85 "Pile foundations."

2. SNiP 11-7-81 "Construction in seismic areas." - Part II, chap. 7.

3. The manual on seismic microzoning. / Ed. O.V. Pavlova. M .: Nauka, 1988.

4. SP 50-101-2004. "Design and construction of foundations and foundations of buildings and structures."

Claims (1)

A seismic-insulating pile, including a factory-made cylindrical structure made of reinforced concrete, placed in a sand-concrete hollow reinforced cylinder, granite sand is poured on the bottom with a layer of the order of one meter, and the space between the reinforced concrete cylindrical structure and the sand-reinforced concrete cylinder is filled to a height of half the sand cylinder.

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