RU2826140C1 - Soil reinforcement method - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to construction (industrial and civil, road and airfield, special earthquake-resistant construction). Method of soil reinforcement using a vibratory milling machine equipped with a power drive, a working member in the form of a saw with endless chains with teeth and unbalancers installed on it with vibrators, with the possibility of changing the angle of inclination, wherein the saw is equipped with an injection tube and nozzles, which perform deep mixing of soil includes stages, at which the saw is installed in the required position, saw is immersed to a given processing depth with simultaneous separation of soil by rotating the saw in a vertical plane, to the saw simultaneously with the rotation by means of unbalancers vibrations are transmitted, after reaching a given depth, polymer-mineral composite mixtures are poured through injection tubes until homogeneous mass is achieved in trenches with simultaneous operation of the saw; the saw of the vibratory milling machine is removed when the required degree of soil reinforcement is achieved.

EFFECT: broader functional capabilities, higher efficiency in soil reinforcement.

9 cl, 6 dwg

Description

The invention relates to the field of construction (industrial and civil, road and airfield, special earthquake-resistant construction).

It can be used in engineering preparation of construction sites for new construction, reconstruction and repair, as well as for strengthening existing foundations of buildings and structures, dams; in road and airfield construction for deep massive stabilization and strengthening of soils, for strengthening the foundations of existing buildings and structures when solving problems of the bearing capacity of the foundation; in earthquake-resistant construction it can be used to reduce the seismicity of the site due to soil conditions.

Deep strengthening of the foundation soils of buildings and structures into a homogeneous massif with controlled characteristics.

State of the art.

Jet grouting, WJE (jet cementation method https://jet-grouting.ru/technologies/jet-grouting-struynaya-cementacia-gruntov/) is known from the state of the art. The method consists of mixing soil and cement mortar. Mixing is performed with a high-pressure liquid jet, which washes away the soil, turning it into a heavy quasi-fluid state, and mixes it with the cement mortar. After the cement hardens, a solid material is formed - soil concrete. Jet technology, due to the high supply pressure of the liquid component, is not effective in fixing small arrays; only wet strengthening is possible. Low speed of work (up to 25 ^m3 /h). Labor intensity for massive stabilization. Only wet mixing. Does not work for mixing, massive stabilization and strengthening of plastic, waterlogged, saline and organomineral waste soils.

The Cutter Soil Mixing technology is known from the prior art (https://www.malcolmdrilling.com/services/cutter-soil-mixing-csm/). The method involves mixing soil and cement mortar. A special drilling rig mixes loose soils by rotating two vertically mounted cutting discs rotating in opposite directions. The discs cut the surrounding soil, simultaneously mixing the injected cement mortar with the soil in place, and the mixing is supplemented by impregnation with cement mortar. As a result of mixing, a wall of modified soil with improved mechanical properties is formed. Ineffective for stabilizing thin arrays, only wet reinforcement. Low speed of work (up to 30 ^m3 /h). Ineffective for massive stabilization.

The ALLU soil stabilization system (DSM) is known from the state of the art (https://www.sautek.ru/soil_stabilization/). Universal hydraulic attachments for excavators, with the help of which the soil (or other stabilized mass)

Mixing is based on the horizontal arrangement of drums and the design of mixing elements. The drums move and mix the material in three directions simultaneously. Shallow depth (up to 5 m). The system is not effective for fixing massive thicknesses (depths), only dry strengthening is possible. Low speed of work (up to 90 ^m3 /h). The system is not effective for deep massive stabilization. Not effective for geotechnical measures.

The Columns/Mass technology (WRS, WRE) is known from the state of the art. A special drilling rig mixes loose soils by rotating the auger tip, and the mixing is supplemented by impregnation with cement mortar. As a result of mixing, a column of modified soil is formed. Installations equipped with interlocked (triple) augers allow for the production of rectangular columns, i.e. barrettes. After the cement hardens, a solid material is formed - soil concrete. Low production speed (up to 75 m3/h). Ineffective for deep massive stabilization. Only wet mixing is possible.

The prior art discloses a device for stabilizing soils with binders (RU 2467125 published 20.11.2012), which includes a vehicle, a rotating platform with drilling equipment and a feed control system for a drill mixer, a cement mixing unit with a receiving bin with a pneumatic loading system, a cement dispenser, a safety net, a mixer, and a water tank including a dosing device made of two chambers, each of which is connected through a dosing device to a mixer, a binder feed unit with a supply tank, a pressure pipeline, a three-way valve, and a binder feed control system. The control and regulating equipment is equipped with direct and feedback communication between humidity and pressure sensors installed in the lower part of the blades of the drill mixer and the working mechanisms of the device. The unit is equipped with a high-speed mixer and a weighing strain gauge batcher, as well as inclinometers installed on the vehicle frame and mast.

The disadvantage of this solution is its inefficiency for deep massive stabilization, and such a device only assumes wet mixing.

The prior art discloses a method and device for feeding binders for soil strengthening (RU 2715783 published 03.03.2020). The method for feeding a binder for soil strengthening is characterized by the fact that the binder feeding device is activated, the soil is crushed, the binders are fed and mixed with the soil, and the binder feeding device is removed from the soil. Before adding binders, their parameters and quantity are calculated, during the soil crushing process, part of the soil is removed from under the binder feeding device, dry bulk substances and viscous suspensions with the addition of drilling mud are fed to strengthen the soil from different containers through pipelines connected to the binder feeding device by one main line. Also known is a device for feeding binders for soil strengthening, comprising a mixing device with blades for loosening and mixing the soil, a feeding device and a container for the binder, characterized in that the mixing device comprises conical drums mounted on a lifting and turning device, screw ridges of augers are made on the surface of the drums, along the ridges of which blades for loosening and mixing the soil are mounted, a pipeline for feeding binders is mounted between the conical drums, connected to the feeding device, made in the form of a screw pump unit, inside which there are main lines for sludge and bulk products, connected at the inlet and outlet of the screw pump unit to a common main line and separated from each other and from the common main line by shut-off valves, an auger is mounted inside the main line for sludge, the screw pump unit is connected by pipelines to parallel-located dosing units for bulk substances and drilling mud, separated from each other by shut-off valves fittings, the bulk solids dosing unit is connected to the bulk solids storage silo, the drill cuttings dosing unit is connected to the drill cuttings tank.

The disadvantage of this solution is its inefficiency for deep massive stabilization, and such a device only assumes dry mixing.

Disclosure of invention

The problem that the claimed invention is aimed at solving is the possibility of strengthening the soil without removing the material being strengthened, as well as the possibility of using both wet and dry mixing technology.

The technical result of the claimed technical solution consists in expanding the functional capabilities and increasing the efficiency in soil strengthening.

This is achieved by the fact that the claimed method is for strengthening the soil using a vibratory milling machine equipped with a power drive, a working element in the form of a saw with endless chains with teeth and unbalancers-vibrators installed on it, with the ability to change the angle of inclination, while the saw is equipped with an injection tube and nozzles that perform deep mixing of the soil, including the stages at which the saw is installed in the required position, the saw is immersed to a specified depth of processing with simultaneous separation of the soil by rotating the saw in a vertical plane, simultaneously with the rotation of the saw, vibration oscillations are transmitted using unbalancers, after reaching the specified depth, polymer-mineral composite mixtures are poured through injection tubes until a homogeneous mass is achieved in the trenches with the simultaneous operation of the saw, the saw of the vibratory milling machine is removed upon reaching the required degree of soil strengthening.

In particular, the solution feed rate is 300 ^m3 /h.

In particular, the solution feed rate is 800 ^m3 /h.

In a particular embodiment of the invention, polymer-mineral composite mixtures are poured until a homogeneous mass is achieved before the stage of immersing the saw to a given depth.

In a particular embodiment of the invention, polymer-mineral composite mixtures are poured until a homogeneous mass is achieved at the immersion stage with the possibility of partially or completely replacing the composition of the massif with concrete mortar.

In particular, the introduction of cement paste or mortar is carried out until a homogeneous mass is achieved when the vibratory milling machine is immersed to a given processing depth, with the possibility of partially or completely replacing the composition of the massif with concrete mortar.

In particular, vibrators can be electrohydraulic, electromechanical, electromagnetic, pneumatic, hydraulic, motor.

In particular, polymer-mineral composite mixtures are poured through injection tubes until a homogeneous mass is achieved in trenches using compressed air.

In particular, polymer-mineral composite mixtures are poured through injection tubes until a homogeneous mass is achieved in trenches using water.

The invention is illustrated by drawings:

Fig. 1 – General view of the vibratory milling machine;

Fig. 2 – General view of the soil strengthening process;

Fig. 3 – Schematic representation of the process of soil strengthening using a vibratory milling machine;

Fig. 4 – Display of the operating process of the working element of the vibratory milling saw;

Fig. 5 – General view of the working element in the form of a saw with endless chains;

Fig. 6 – Block diagram of the method implementation.

The following structural elements are indicated by numbers on the figures:

1 – stage of installing the saw in the required working position perpendicular to the ground, 2 – stage of immersing the saw, 3 – stage of transmitting vibration oscillations using unbalancers, 4 – stage of extracting the saw of the vibratory milling machine upon reaching the required degree of soil strengthening.

Implementation of the invention

This invention uses the principle of mixing with a power drive and a working element in the form of a saw with endless chains with teeth. The endless chain is equipped with extenders up to 1 m to increase the speed and volume of processing of deep arrays. The saw blades are rotated by means of a system of two chains, the saw itself is controlled from the driver's cabin. Due to the location of the blades, the soil is not removed, but mixed with the solution on site. This invention allows to reduce preparatory and construction work using a minimum amount of binder, namely, polymer-mineral composite mixtures. Allows to arrange strong and water-blocking soil-cement walls in one pass by mixing natural soil with a pumped cement suspension and / or dry components. Deep mixing can be carried out both wet and dry.

Deep mixing is performed by mechanically dividing the soil by moving the working tool, with the introduction of polymer-mineral composite mixtures o, which is homogenized with the soil during immersion and/or extraction. In the dry mixing method, the introduction of polymer-mineral composite mixtures is usually performed using compressed air thanks to an air compressor and an air drying unit. In the wet mixing method, the introduction of the binder, namely polymer-mineral composite mixtures, is usually performed using water thanks to a pressure pump.

Mixing can be performed with simultaneous deep vibration of the massif by means of special-purpose equipment used for compaction of the mixture, by means of oscillatory (vibrating) action of vibratory pressing plates and/or deep immersion vibrators in combination, mounted on the working tool, providing compaction of the side walls and the massif being strengthened, which will eliminate air bubbles and cavities where the solution has not entered, which lead to a decrease in the strength of the mixture, deterioration of its quality and reduction of its service life. Unbalancers are located on the body of the working tool and, during its operation, create oscillatory movements transmitted to the vibrator. The vibrator mount on the body of the working tool along its entire length acts as a bridge transmitting vibrations from the engine to the vibrator. The mover in the vibrator serves as a source of energy that sets the shaft with unbalancers in motion. Depending on the method of obtaining energy, the mover can have an electromechanical, pneumatic, electromagnetic, hydraulic or motor drive.

The basic principle of operation of concrete vibrators is the impact of vibrations of a vibrating nature on the building solution, leading to the compaction of the constituent particles of the concrete solution, created, in particular, with the help of a concrete mixer.

When on the working tool in the strengthened massif, the work is supplemented by vibration, transmitting the energy of vibration oscillations to the adjacent layers of the mixture. As a result, the viscosity of the composition decreases, and the mixture acquires the properties of a heavy flowing liquid. At the same time, like all liquid substances, it tends to fill all available cavities and holes, displacing air. At the same time, under the influence of gravity, the vibrating particles of the mixture tend to take the most stable position relative to each other. The result is a homogeneous, dense structure of the stone, without air cavities and, as a consequence, more durable and high-quality indicators of the deep massif.

Vibrators can be electrohydraulic, electromechanical, electromagnetic, pneumatic, hydraulic, motor.

The addition of additives can be carried out on the surface of the working element, at the immersion stage, after immersion, with the possibility of partially or completely replacing the composition of the massif with concrete mortar.

The dry mixing procedure must follow the design specifications.

The given design capabilities achieve the technical result of expanding the functional capabilities and increasing the efficiency in soil strengthening.

Claims (14)

1. A method for strengthening soil using a vibratory milling machine equipped with a power drive, a working element in the form of a saw with endless chains with teeth and unbalancers with vibrators installed on it with the ability to change the angle of inclination, while the saw is equipped with an injection tube and nozzles that perform deep mixing of the soil, including the stages at which: - set the saw to the required position; - the saw is immersed to a specified processing depth with simultaneous separation of the soil by rotating the saw in a vertical plane; - simultaneously with the rotation of the saw, vibration oscillations are transmitted using unbalancers; - after reaching the specified depth, polymer-mineral composite mixtures are poured through injection tubes until a homogeneous mass is achieved in the trenches while the saw is operating simultaneously; - remove the saw of the vibratory milling machine when the required degree of soil strengthening is achieved. 2. The method of strengthening the soil according to paragraph 1, characterized in that the solution feed rate is equal to 300 ^m3 /h. 3. The method for strengthening soil according to paragraph 1, characterized in that the solution feed rate is equal to 800 ^m3 /h. 4. The method of strengthening the soil according to paragraph 1, characterized in that polymer-mineral composite mixtures are introduced until a homogeneous mass is achieved before the stage of immersing the saw to a given depth. 5. A method for strengthening soil according to paragraph 1, characterized in that polymer-mineral composite mixtures are introduced until a homogeneous mass is achieved at the immersion stage with the possibility of partially or completely replacing the composition of the massif with concrete mortar. 6. A method for strengthening soil according to paragraph 1, characterized in that cement paste or mortar is introduced until a homogeneous mass is achieved when the vibratory milling machine is immersed to a given processing depth with the possibility of partially or completely replacing the composition of the massif with concrete mortar. 7. A method for strengthening soil according to any of paragraphs 1-6, characterized in that the vibrators are electro-hydraulic, electromechanical, or electromagnetic, or pneumatic, or hydraulic, or motorized. 8. A method for strengthening soil according to any of paragraphs 1-7, characterized in that polymer-mineral composite mixtures are poured through injection tubes until a homogeneous mass is achieved in trenches using compressed air. 9. A method for strengthening soil according to any of paragraphs 1-7, characterized in that polymer-mineral composite mixtures are poured through injection tubes until a homogeneous mass is achieved in trenches using water.