RU2516037C2 - Method to reinforce foundations of buildings and structures, prone to action of forces of frost heaving of soils - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to construction, in particular, to reconstruction of underground parts of buildings and structures with reinforcement of existing foundations, exposed to considerable deformation from action of frost heaving forces. Reinforcement of foundations of buildings and structures prone to action of sign-alternating loads of soil freezing and thawing. Reinforcement of the foundation by augercast piles is carried out at the moment of maximum possible lifting of a building or a structure by forces of frost heaving.

EFFECT: invention provides for liquidation of negative impact of forces of frost heaving at construction structures of buildings and structures.

3 dwg

Description

The invention relates to the field of construction and reconstruction of underground parts of buildings and structures, and in particular to a technology for strengthening the existing foundations of buildings and structures experiencing significant deformations from the action of frost heaving forces.

There is a method of reinforcing foundations in order to prevent frost heaving, which consists in hardening dusty clay soils with a high-pressure injection (cement, silt cement, cement-sand mortar) (see A. Polishchuk. Fundamentals of design and construction of foundations of reconstructed buildings. - Northampton: STT; Tomsk: STT, 2004. P. 378-379).

The disadvantages of this technical solution include the following. By pumping the solution into the soil through thin pile injectors, the thickness of the soil under the foundation is enhanced. In this case, the foundation body is not pierced by piles and the load is transferred to the underlying layers through the reinforced soil thickness: in this way, significant reinforcing mortar costs are required to reach deep-seated bedrock. High-quality distribution of the solution in the soil is possible only for loose (weakly gravelly) soils, which greatly complicates the application of the method in areas with a predominance of clay highly gravelly soils.

There is also known a method of strengthening the foundations of the foundations, involving the injection of quick-setting cement mortar into pipes installed in wells drilled through the supporting part of the foundation and soil. The pipes are made of elastic plastic with closed lower ends, and the middle part of these pipes is equipped with metal pipes located between the bottom of the foundation and the soil layers with increased bearing capacity (patent for invention 2335602, application 006144521/03, 13.12.2006).

The disadvantages of this technical solution include the need for accessible space on the surface of the foundation for the possibility of installing high-quality vertical wells under piles of a rather complex combined design.

The closest in technical essence and the achieved result is a way to strengthen the foundations by transferring the load from the foundation to the injection piles (see A. Polishchuk. Fundamentals of design and construction of foundations of reconstructed buildings. - Northampton: STT; Tomsk: STT, 2004. p. 352 -353).

The disadvantages of this technical solution include the need for a satisfactory condition of the slab part of the foundation and the high probability of further deformations of the foundation with an increase in frost heaving forces as the soil freezes.

The task to which the proposed technical solution is directed is to stop seasonal deformations of the foundation caused by the forces of frost heaving of the soil.

The technical result achieved when solving the problem is expressed in the removal of the load from the foundation from the weak, heaving soils of the base and its transfer to durable incompressible layers.

The problem is solved in that the foundation is reinforced with piercing piles piercing its body, resting on the underlying strong layers of soil, at the moment of the greatest seasonal rise of the base soil caused by frost heaving forces. Thus, with the disappearance of such forces with seasonal thawing of the soil, the foundation does not deform. In this way, the influence of frost heaving forces on the foundation is neutralized, and further cycles of freezing-thawing of the soil stratum do not affect the bearing capacity of the reinforced foundation, since it changes its volume at new volume boundaries.

A comparative analysis of the essential features of the proposed technical solution with the essential features of analogues and prototype indicates its compliance with the criterion of "novelty."

In this case, the distinguishing features of the claims solve the following functional tasks.

The sign "... reinforcement of the foundation with injection piles is carried out at the moment of the maximum possible raising of the building or structure by frost heave forces" ensures the prevention of further deformations of raising and lowering the foundation due to the absence of frost heaving forces at the base of the foundation, since the reinforcement is performed at the maximum height of soil outburst.

Figure 1 shows a diagram of a vertical section of the soil and the foundation. Figure 2 shows the same diagram at the time of maximum lifting of the soil of the base, under the action of frost heaving forces. Figure 3 shows the foundation reinforced with piercing piles piercing his body during the period of the beginning of seasonal thawing of the soil.

1 - Foundation.

2 - Downy soil.

3 - Incompressible soil.

4 - Bored injection pile.

5 - Emptiness resulting from thawing of the soil.

Strengthening the foundations of buildings and structures subject to alternating loads of freezing and thawing soils, characterized in that the foundation is reinforced with bored piles at the moment the building or structure is raised as much as possible by frost heaving.

Claims (1)

Strengthening the foundations of buildings and structures subject to alternating loads of freezing and thawing soils, characterized in that the foundation is reinforced with bored piles at the moment the building or structure is raised as much as possible by frost heaving.

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