BG60523B1 - Method for the preparation of a pile and instrument for its making - Google Patents

Abstract

The method and the instrument are applied in the reconstruction of buildings. They improve the carrying capacity and reduce the building time. The method includes the supply of hardening material (6) in the hole (1) or in the foundation by the excitation of high voltage electric discharges in the material (6) and shifting the zone (7) for feeding the material and excitation of the high voltage electric discharges at the height of the formed pile. The summation energy of the high voltage electric discharges at a specific depth ensures the enlargement of the respective section in hole (1) of the foundation up to the preset diameter of the pile at that depth. A zone (8) with reinforced base of increased strength and a zone (9) with the compacted base with improved civil engineering qualities are formed around the formed pile under the effect of the high voltage electric discharges. The instrument has tube (3) for feeding the material and electric discharger with electrodes (10 & 11) fitted coaxially and divided between them, fitted to the insulation rod (15) getting inside the first electrode (10). The latter is connected to the end of the tube (3) inside of which its outlet hole (17) is found, so that its axis shall be parallel to the axis of the tube. The distance from the second electrode (11) to the outlet hole (17) of the tube (3) is no less than the size of the clearance (16) between the electrodes.

Description

(57) The method and the tool are used in the reconstruction of buildings. They increase the load-bearing capacity and reduce construction time. The method involves feeding the solidifying material (6) into the hole (1) or at the base with the excitation of high-voltage electrical discharges into the material (6) and moving the area (7) to feed the material and initiating high-voltage electrical discharges at the height of the formed pilot. The total energy from high-voltage electrical discharges at a certain depth provides an extension of the corresponding section in the orifice (1) or base to the predetermined pilot diameter for that depth. Under the action of high-voltage electrical discharges, an area (8) with a reinforced base with increased strength and a zone (9) with a compacted base with improved construction properties are created around the formed pilot. The instrument has a tube (3) for supplying the material and an electrical arrester with coaxially arranged and separated electrodes (10 and 11) attached to the insulating rod (15) passing inside the first electrode (10). The latter is connected to the end of the tube (3) on which its outlet (17) is located so that its axis is parallel to its axis. The distance from the second electrode (11) to the outlet (17) of the tube (3) ) is not less than the size of the electrode gap (16).

claims, 6 figures

(54) METHOD OF MANUFACTURING THE PILOT AND THE INSTRUMENT FOR ITS IMPLEMENTATION

The invention relates to a method and tool for the manufacture of piles, which are used in the construction of pilot foundations in the construction process and in the reconstruction of buildings and engineering facilities.

There is a known method for making a pilot / DE, C, 2651023 / which is used to strengthen the existing foundations and includes drilling a borehole with machines with shock-and-drilling under protection with casing, fitting and inserting into the pipe opening for injection of cement-sand mortar. After injection of the mortar prior to its hardening, an injection pipe is passed through it, under which a cement mortar is forced under increased pressure to form an expansion at the base of the formed pilot.

The disadvantage of this method is the low bearing capacity of the pilot on its lateral surface, since the drilling hole is formed by excavation of the soil and a layer of undamaged soil is created on its wall, which does not cooperate with the pilot. For this reason, the countertop should be of great length to support its lower end at the solid base (rock, moraine).

The disadvantage of this method is also the low productivity due to the need to consistently perform the drilling operations of the hole, installation of casing, removal of the drilling tool, installation in the pipe opening for injection of cement sand, pouring the hole with this solution, removal of casing and pipes for injection of cement-sand mortar, mounting in the opening of injection pipe and injection of cement, mortar, wherein between any two of said successors Our operations should be subject to a technological break in connection with the hardening of the pilot material, which acts as a seal for high pressure injection of cement mortar.

A tool is known for making a pilot / US, A, 4060994 / which has a tube for supplying the solidified solution connected to the solution pump. The pipe is inserted into the opening and pressurized into it by the solidified material that forms the body of the pilot, while simultaneously removing the pipe according to the degree of filling of the opening with the material.

The disadvantage of the tool is that the pilot produced by the pilot has a low bearing capacity, since the tool ensures only the feed of material into the hole without sealing the surrounding base, the decrease in the bearing capacity of the pilot is also due to the fact that in the feed process of the solidified material in the opening is inevitably mixed with the water or with the base. In addition, it is possible for the pilot density to be altered by its height due to water or clay piercing and penetration into the pipe.

The disadvantage of the tool is also that, in its use, the pilot construction time is prolonged, since, in addition to drilling the hole and pouring it with a curing solution, it is necessary to perform operations to prevent the hole from collapsing on its walls, i.e. . mounting it in casing pipes or filling it with clay solution.

It is an object of the invention to provide a method and tool for pilot construction that would allow the formation of a pilot around an area in the high-density earth layer involved in working with the pilot, and thereby increase the pilot's carrying capacity, and also to reduce pilot construction time by reducing the number of operations.

The problem is solved by a method for manufacturing piles by feeding high-voltage electrical discharges (discharges) into the pilot formation zone of the solidifying material, according to the invention, whereby high voltage electrical discharges (discharges) are excited in the pilot formation zone. the feed material and the electrical discharge excitation is positioned at the depth of the pilot formation area, and the total discharge energy at a certain depth from the pilot formation area is such that increase the diameter of the relevant section from this area to the specified pilot diameter at this depth.

The increase in the carrying capacity of the pilot is related to the fact that when the high-voltage discharges are excited according to the proposed method, a periodic surge of pressure is applied in the solidifying material supplied to the pilot forming zone, which leads to the expansion of this zone, compaction of the base around it, draining the free water and the water in the pores and filtering the solidified material into the released pores of the substrate. As a result, a reinforced base area and an area with a compacted base around it are created around the pilot. In addition, the proposed method allows, by varying the total energy from the discharges along the depth of the pilot-forming zone, to modify the cross-sectional area of the pilot at its height, thereby adjusting the carrying capacity of the pilot during its construction, depending on the type of base.

The proposed method does not envisage operations to protect the walls of the opening from collapse by existing known methods (casing, clay, mortar), the pilot making time is shortened at the expense of combining in time the material feed operations, the formation of pilot aperture and base seal.

The curing material can be fed into the pioneer hole, which is the pilot formation area.

The curing material can also be fed directly to the base, which in this case is the pilot formation area. In this way a further reduction of the pilot construction time is achieved at the expense of the exclusion of the hole drilling operations.

In the case of a pilot with a height-varying radius when moving the material feed area and emptying excitations, it is appropriate to vary the number of empties so that at a certain depth of the pilot formation area that number is in direct dependence on the pilot's specified radius at this depth.

In the case of a pilot with a height-varying radius when moving the material feed area and emptying excitations, the frequency of alternation of empties may be changed so that its significance for a certain depth of the pilot formation area is is in direct relation to the pilot's given radius at this depth.

When constructing the pilot in the piercing hole, it is appropriate to determine the number η of the deflections at a certain depth of the pilot formation zone by the formula n = exp ^r ~ 1 κ (ζ '^ ΰΤ-Γ,) in which r denotes the radius of Driver for a particular depth in meters, r _o -radius a pioneer hole, in meters, W -energiyata a discharge at a certain depth, in joules, K - ratio of intensity of accumulation of irreversible deformations in the core, χ - factor depending of the properties of the substrate.

According to one of the embodiments of the pilot directly at the base, the feed zone and the excitation zone are moved by the depth of the base, whereby the number η of the discharges at a given depth is determined by the formula η - exp ^r ~ r ____ 2 κ * Vw ~ in which r denotes the specified pilot radius at a certain depth, in meters, W - the energy of one emptying at a certain depth, in joules, K - coefficient of intensity of accumulation of irreversible deformations at the base, χ-coefficient depending on the properties based on.

According to another embodiment, the pilot feed area directly at the base of the material feed and emptying excitation zone is moved to the depth of the base and, after reaching a depth corresponding to the predetermined height of the pilot, the material feed and emptying excitation zone moves upwards, the energy W, of one emptying motion of the feed zone and of emptying the emptying zone down is determined by the ratio

W1 - / j / 3

13,12 as j denotes the maximum cross-sectional dimension of the tool providing the material feed and excitation of the discharges, in mm, f coefficient of strength on the basis of the Protodyakov scale, and the number η of the discharges at a certain depth when moving the indicated zone upwards is defined by the ratio η - exp ^r κ (z '^ W ^ 0,5 d) as W denotes the energy of one emptying at this depth when moving the material feed zone and exciting the empties upwards, in joules, d - the set the radius of the pilot on this dol Ochin, in m, k - ratio of intensity of accumulation of irreversible deformations in the core, χ - factor depending upon the properties of the base, d maximum cross-sectional dimension of the tool, providing a supply of material and the excitation of discharges in m.

In the manufacture of a cobblestone pilot, it is appropriate to calculate in the feed area and excitation of the discharges in step Δ h determined by the ratio

Ah = r '(1 -b) sin {2arctg [(1 -b) tg -]} for r'> r 5 and Ah = r '(lb) tg {2arctg [(lb) tg -]} for r' <r as b - denotes the permissible relative deviation from the specified pilot radius, α the specified pilot cone angle, r 'and r the specified pilot radius at the transitional and subsequent steps, respectively.

The problem is also solved by a pilot making tool comprising a tube for supplying the solidifying material, and according to the invention further comprises an electric arrester having coaxially and electrodes disposed with each other, the first of which is arranged as annular and arranged on passing through its an insulation rod inside and the second one attached to the end of that rod and connected to a conductive rod located inside the insulation rod and connected to the central core of a coaxial cable, the screen shell to which is connected to the first electrode, wherein the diameter of the second electrode is larger than the diameter of the insulating rod, the first electrode is fixedly connected to the end of the tube on which its outlet is located, so that the axis of the first electrode is parallel to the axis of the tube and the distance from the outlet of the tube to the second electrode is not less than the value of the electrode gap.

Due to the presence of a thinner which is located on the tube for supplying the solidifying material near its outlet, the proposed tool can be used in carrying out the method according to the invention i.e. it allows for the simultaneous excitation of high-voltage discharge into the solidifying material. In this case, the tool is suitable for pilot construction both in the drilling hole and in the base.

The invention is explained in more detail by describing the best options for its implementation and the accompanying figures, of which:

Figure 1 illustrates a method for making a pilot according to the invention in one embodiment;

Figure 2 is a method of manufacturing a pilot according to another embodiment of the invention;

Figure 3 is a first step of a pilot manufacturing method according to a third embodiment of the invention;

FIG. 4 is a second step of the method for making a pilot according to a third embodiment of the invention; FIG.

Figure 5 is a pilot making tool according to the invention;

Figure 6 is a variation of the characteristics of the base around the pilot made according to the invention.

The proposed method is as follows.

By any of the known methods, for example by rotary drilling, an initial opening 1 (FIG. 1) of a diameter smaller than the diameter of the pilot being produced (in the case of a cylindrical pilot) or of the minimum diameter of the developed pilot / in in the case of a pilot with height-varying diameter /. An armature is fitted in the opening 1 if necessary, and at the bottom of the opening 1 the tool 2 containing the pipe 3 for supplying the curing material and the electrical discharge 4. The pipe is lowered. 3 is connected to the solution pump pa / not shown / and the arrester 4 to the current pulse generator 5. Electrically conductive curing material 6 is supplied continuously or in portions through the pipe 3, for example on the basis of cement or synthetic liquid materials, and current pulses are applied from the generator 5 to the electrodes of the arrester 4 and high-voltage electrical discharges are excited in the material 6. Thus, the zone 7 below the lower edge of the tool 2 is the material feed and excitation zone for high-voltage electrical discharges. From each high-voltage electrical discharge in the aperture 1, partially or completely filled with the material 6, a surge pressure is produced. As a result of impact, the material 6 is sealed in the zone 7, the expansion of the opening 1 in its lower part, the drainage from the adjacent base of the free water and the water from the pores and the penetration of the material 6 into the pores and voids of the base released from water with the formation of zone 8 with reinforced base having increased strength, and also zone 9 compacted base around zone 8 having improved construction properties / increasing the bearing capacity of the base due to the reduction of porosity and increase in fashion and deformation of the base /. The free space formed by the seal of the material 6 is constantly filled with new portions of the material so that each subsequent high-voltage electrical discharge flows into a new volume of solid material.

The total energy from high-voltage electrical discharges, in this case their number is chosen so as to allow the expansion of the lower portions of the aperture 1 to the required pilot diameter at its lower portion. This is how the pilot base is formed.

It has been experimentally found that the energy at each discharge should be at least 5 kJa, where the pressure of the flow in the orifice 1 can be increased from 50 to 200 mPa. For discharges with an energy of less than 5 kJ, the formation time of the pilot exceeds the material curing time, resulting in a decrease in the strength of the pilot material. It is not recommended to initiate energy discharges of more than 200 kJ because increasing the load on the borehole walls may result in exceeding the permissible velocity of oscillations at the base and in a seismically harmful effect on adjacent structures and structures. In addition, as the discharge energy increases, the overall performance of the installation that implements the method increases.

Then the tool 2, and consequently the area 7 below for material feeding and excitation of the discharges, are moved upwards, as shown by the arrow in Fig. 1, with the step Ah and the process described above is repeated as the following sections of the pilot's body are formed. However, in the case of a pilot with height-varying radii, the number of discharges in the next steps increases compared to that of the previous step by increasing the radius of the pilot and vice versa. The magnitude of the Ah step is determined according to the prescribed law for changing the pilot radius by its height and the required precision in pilot development. For example, in the development of cylindrical piles, the Ah step remains constant and its value is calculated by the formula

Ah = r sin [arc cos (1 - b) J 6 in which r denotes the specified pilot radius, in the tolerance of the specified pilot radius.

When designing a conical pilot, the Ah step is determined by the ratio

Ah = r '(l-b) sin {2arctg [(l-l) tg— ι)

, .Ί 'at r> r ^a 11 or Ah = r' (lb) tg {2arctg [(ll) tg P at r <r as r and r "denote the specified radius of the pilot, respectively in the previous and next steps, and - set angle of cone pilot.

At this step value, the number η of the discharges at each step can be chosen such that the radius of the resulting pilot section of each step is smaller than the given radius d of magnitude bd. The reason for this is that at each step a pilot section is made in the form of a spherical segment with a surface area that exceeds the surface area of the same section of the pilot at a given radius. Thus, the method allows to a certain extent to reduce the volume of the manufactured pilot without impairing the bearing capacity and at the same time to obtain material savings.

The described procedure is continued until the pilot body is fully formed at height h, after which tool 2 is removed. When feeding material 6, its flow rate is adjusted so that its level in the pilot hole 1 is on the marking of the outlet.

Experimentally it was found that as a result of the operation in the first discharge radius d _o of the pilot hole 1 is increased to a value of d _p which is given by ^Γ ι = X m ⁸ which - is the coefficient which depends on the properties of the base, W- the energy of one discharge, J.

After n-number of discharges, the increase in radius Δγ _π = D - D of the pilot hole 1 can be determined by the empirical dependence D _{n n} = Ar, (Kin η + 1) 9 as A r = r - r _o denotes the increase in radius of the pilot orifice under the action of the first emptying, K is the intensity factor of the accumulation of irreversible deformations at the base.

It follows from the expressions / 8 / and / 9 / that the formation of a section of the pilot of radius d requires η number of discharges, determined as follows:

η “exp ^d

10

K (xVw “-r _o ) y

The coefficient 1 ^L is K and y are determined empirically. The coefficient K depends on the condition of the base and its values are in the range from 0.2 to 0.7. The coefficient depends on the type of substrate and increases as the density of the substrate increases. For sand this coefficient is 0.00163 and for sand and clay soil it is 0.0021.

In the case of developing a pilot with a height varying radius, the total energy of the discharges changes depending on the degree of displacement of the instrument 2 by varying the number of discharges in proportion to the required change in the radius of the pilot orifice that follows from the expression / 10 /. In this case, the tool moves in step Ah, and the frequency of discharges in this case is constant and is selected, depending on the predetermined design time of the pilot, taking into account the properties of the solidifying material used, but not less than 0. 5 Hz. It is also possible to adjust the total energy in the height of the formed pilot by varying the frequency with which the discharges follow, in accordance with the change in the radius of the pilot. Obviously, the larger the required pilot radius for a given depth, the greater the frequency for that depth at which the discharges follow, and vice versa. In this case, the tool 2 is continuously moved at a constant speed.

When selecting frequency values, s

When selecting values for the frequency that follows the discharges, it is necessary to take into account that the process of forming the pilot involves expanding the pilot orifice 1 by compacting the base around it. This process proceeds differently, depending on the ratio between the discharge rate and the rate of pressure drop in the pilot orifice, which is filled with material. If the frequency at which the discharges follow is not less than 0.1 Hz, then any subsequent discharges shall take place after the complete pressure drop and the consolidation of the substrate which, upon excitation of the discharges, becomes more dense. By increasing the frequency above 0.1 Hz, the process of destruction of the base structure and its compaction are combined over time, which accelerates the formation of the pilot body. On the one hand, the increase in the frequency with which the discharges follow allows to reduce the energy of each discharge, while providing at the same time the total energy sufficient to destroy the structure of the base and its compaction. On the other hand, at a higher frequency of emptying, each subsequent emptying operates under conditions of incomplete consolidation on the basis determined by its filtering properties, which determine the rate of discharge. As a result, the efficiency of each discharge is reduced and the energy losses of the pilot are increased. For example, at an initial value of the base porosity ratio of 0.690 in the case of increasing the frequency with which the discharges follow, from 0.09 Hz to 6 Hz, the effect of compaction from one emptying is reduced 9-fold. Variation in the frequency at which discharges follow allows the pilot's speed to be adjusted at a very wide interval. It is not recommended to reduce the emptying frequency below 0.5 Hz, since in this case the time for the formation of the pilot body becomes commensurate with the time for material hardening. In this case, the effect of the discharges is unfavorable for the formation of the material structure upon hardening, thus reducing the carrying capacity of the pilot. The upper limit of the frequency at which discharges follow is limited by the capabilities of the current pulse generator.

In the present embodiment, the pilot opening 1 has a pilot formation area. In accordance with another embodiment of the pilot, the base is used as a zone for its formation. the pilot is developed directly at the base without drilling a pilot hole. In this case, tool 2 is applied at the base of a depth of 0.3 to 0.5 m by any of the known methods for this purpose, for example by rotary drilling or by ramming, and then, as described above, a curing solution is supplied 6, wetting a section of the base and initiating in this section high-voltage electrical discharges in such a number that provides the formation of the upper section of the pilot with a given diameter. The tool 2 is then moved in depth to the base by the step Ah, which is determined by the equations (6) or (7), depending on the shape of the pilot being manufactured. Insofar as the material 6 is fed to the base, the number η of the discharges at a given depth is greater than that at the material feed into the pilot orifice and is determined by the ratio η - exp ^r 'W h ¹¹ κΧ Vw as r denotes a given radius of pilot for a certain depth.

After reaching a depth h equal to the height of the pilot, the tool 2 is removed and a fitting is installed in the pilot, which is necessary. In the process of pilot construction, the material flow 6 is adjusted so that its level is at the mark in the top of the pilot.

Unlike the option of pilot construction in the pilot orifice, in this case an additional increase of the bearing capacity of the pilot is achieved because the base is not dug when the pilot hole is drilled and the pilot formation is made by moving the base from “zero. "To the specified radius of the pilot. In addition, the undoubted advantage of the workmanship at the base is the profit in the reduction of material losses and time losses, the exclusion of the pilot hole drilling operation is related.

Also, as in the manufacture of 5 pilots with radius-altitude change in a pilot orifice, the displacement of the instrument 2 may not change the number of pulses, but the frequency with which they follow, in accordance with the statutory amendment 10 of the radius of the pilot at his height. The above considerations regarding the choice of discharge energy and the frequency with which the discharge is followed remain valid even in the case of the production of 15 pilots directly at the base.

The construction of a pilot at the top-down base is appropriate for reinforcing foundations in existing buildings and structures when 20 gaps and boreholes formed as a result of groundwater action are located below the foundation. There is also another way of making piles at the base, which is preferable for the construction of intermediate supports in 25 dungeons of reconstructed buildings and structures or the construction of new foundations for the construction of buildings and structures. According to this embodiment, tool 30 2 (FIG. 3) is similarly crammed into the base and the electrically conductive curing material 6 is supplied with excitation at the base of high-voltage discharges. However, the energy of the discharges is selected in such a way that 35 from each of them below the bottom edge of the tool 2 forms a blast pit with a radius approximately equal to half the diameter of the tool 2. Formation beneath the blasting tool facilitates 40 its passage into the base-tool 2 submerges itself or penetrates the base with little effort. In order to ensure self-immersion of the tool 2 at the base, the value W 'of the energy of one discharge 45 must be equal to

d means the maximum size of the 50 cross-sections of the instrument, in mm, is the strength factor on the basis of the Protodyakov scale.

The frequency ν with which the discharges are carried out shall be chosen to provide the required velocity V for ramming the instrument calculated by the formula

V

V ------ c -----, Hz. 13

5.9 \ / W, / f

The speed in expression / 13 / is measured in m / h.

Upon reaching a depth corresponding to the pilot title marking at the base, the pilot is made as described, but in the downward direction, raising the tool 2 / figure 4/ in step Ah, whereby the number η of the discharges for each step are determined by the ratio η - exp ^r ~ κ 0.5 d) ¹⁴ as W denotes the energy of one discharge of this step, in joules.

Thus, in this case, the construction of the pilot is performed from the bottom up, and the material feed and excitation of the discharges upon delivery of the tool at the place of formation of the bottom of the pilot is performed only to reduce the base resistance in the downward movement of the tool.

The pilot making tool has a tube 3 (FIG. 5/) for supplying the solidifying material and an electrical arrester with electrodes 10 and 11 arranged coaxially and directed in the direction of their axes. Pipe 3 consists of several sections ordered when the tool is driven into the pilot orifice or at the base, Fig. 5 shows the end of the lower section of the pipe

3. The electrode 10, which is at the top of the working position of the tool, is made in the form of a ring screwed onto a metal sleeve 12, and the electrode 11 is in the form of a cone with a large cone angle, facing downwards. Such an embodiment of the lower electrode 11 facilitates the insertion of the tool into the base, but not necessarily, the lower electrode may be made in the form of a flat disk or ring. As a whole, the bottom electrode 1I is provided with a conductive rod 13 passing along the axis of the discharge gap inside the sleeve 12, and is connected to a central core of the coaxial cable 14 connected to one of the terminals of the current impulse generator / figure no. is shown/. The length of the cable 14 must be such as to allow the tool to be submerged at a predetermined depth corresponding to the height of the pilot being manufactured. The space inside the sleeve 12, the guide rod 13 tightly to the lower electrode 11 and the cable section 14 connected to the rod 13 are flooded with insulating material, for example polyethylene, which forms an insulating rod 15. The diameter of this rod 15 is smaller than the diameter of electrode 11, for example by 8 to 10 mm, such that between the electrodes the gap 16 is the space between the lower face of the electrode 10 and the annular peripheral portion of the upper surface of the electrode 11 extending beyond the rod 15.

The upper electrode 10 is welded to the end of the tube 3, and the distance of the outlet opening 17 of the tube 3 to the lower electrode 11 is not less than the value of the electrode gap 16. Another connection of the tube 3 with the electrode 10 is possible, for example the tube 3 can be screwed into this electrode, in which case the regulation of the size of the electrode gap 16 is accomplished by moving the electrode 10, separating the tube 3 from the electrode 10, which facilitates the preparation of the tool for operation.

The pipe 3 is electrically connected to the screen jacket of the coaxial cable 14 connected to the other terminal of the current impulse generator connected to its housing. For the forces acting between the electrodes 10 and 11 in the discharges so as not to interfere with the fixed attachment of the conductive rod 13 in the insulating rod 15, the conductive rod 13 must have annular projections 18.

A non-return valve 19 is installed at the bottom of the pipe 13, adjacent to its outlet 17, to prevent particles from entering the base into the pipe 3. This function, instead of the valve 19, can fulfill the visor attached to the pipe 3 below its outlet.

The electrode 10 and the electrode 11 with the guide rod 13 are made of core steel with a hardened surface layer to reduce metal erosion from the electrode surface during discharges.

The tool is positioned in a vertical position, for example in a drilling apparatus (not shown in the figure), with the pipe 3 attached to the rotating part of this apparatus. By moving the electrode 10 along the sleeve 12, the required size of the inter-electrode gap 16 is established to provide the conversion of the discharge energy into mechanical operation with the highest efficiency. When making a pilot in a pilot orifice, the tool is lowered to the bottom of the pilot orifice, extending through sections the pipe 3, depending on the degree of descent. After reaching the bottom of the pilot hole, the cable 14 is connected to the output of the current pulse generator, and the pipe 3-to the pump with the solution (not shown). The curing material is pressurized through the pipe 3 to the bottom of the pilot orifice and at the same time the generator is switched on, which supplies current impulses to the electrodes 10 and 11. High-voltage discharges are created in the electrode gap 16, which leads to the expansion of the lower section of the electrode. the pilot orifice filled with curing material, and until the base seal is fixed around this portion. Depending on the degree of formation of the pilot sections, the tool gradually rises. The movement of the tool is controlled, for example, by the marking affixed to the side surface of the pipe or by the feed rail of the drill unit.

In the case of making piles at the base, the tool is driven into the base at a depth of 0.3 to 0.5 m and the pilot is shaped in a similar manner by pushing the tool at a depth of the base.

Figure 6 presents experimental data showing the variation of the strength of the substrate around the pilot 20 made according to the invention. The horizontal axis of the graph shows the distance from the pilot axis in meters and the vertical depth h in meters. As can be seen from the figure

6, around the pilot 20 formed zone 8 of the reinforced base with a strength R at a pressure of 0.4 to 1 MPa and a zone of compacted base, which consists of three additional zones 21,22 and 23, which mat the values of module E of deformation, respectively 480 MPa, 330 MPa and 310 MPa. To the left of the graph depicting the pilot 20 with its base attached is an engineering and geological section of the site on which this pilot was made. The substrate layer 24 is medium size sand with a porosity coefficient of 0.75, and the layer 25 represents fine water-saturated sand (0.72, E = 190 MPa), the layer 26 is dust-saturated sand / = 0.67, E = 150 MPa, the internal friction angle of the substrate is 28 °, the adhesion C is 0.04 kPa / and the layer 27 is crushed by water-saturated sand with the same characteristics as layer 25. Under the layer 27 there is a moraine. By comparing the characteristics of the starting base with the characteristics of the base adjacent to the pilot 20, it can be seen that the bearing capacity of the base around the pilot and below the heel increases from 1.5 to 3.0 times.

The following are examples of embodiments of the process of the invention.

Example 1. A section of a cylindrical pilot with a diameter of 0.3 m and a height of 1 m is made into a sand base saturated with water when the tool is moved from top to bottom in the manner described in the explanation of Figure 2. The curing material is cement solution.

The coefficient K of the intensity of accumulation of irreversible deformations at the base is 0.54.

The coefficient /, depending on the properties of the substrate, is 0.00163.

The maximum cross-sectional dimension of the tool is 0.09 m.

The consumption of cement mortar is 2.3 m ³ / hour.

The energy of one discharge is 50 kJ.

The frequency of discharges is 1 Hz.

The number of steps is 14.

The step size is 0.071 m

The number of discharges per step is 16.

The time to form a single-step pilot section is 0.0044 hours.

The time to form a pilot section of 1 m length is 0.062 hours.

Example 2. Making a section of a cone-shaped pilot with a minimum diameter of 0.3 m, a height of 1 m and a hull angle of 14 ° in a dense sand-clay base by moving the tool from bottom to top, as described in the consideration of Fig. 3 and 4. The curing material is a cement-sand solution.

The coefficient K of the intensity of accumulation of irreversible deformations at the base is 0.7.

The coefficient /, depending on the properties of the substrate, is 0.00302.

The maximum cross-sectional dimension of the tool is 0.09 m.

A / Tooling at the base of a depth of 1 m.

The energy of one discharge is 33.34 kJ. The frequency of discharges is 0.18 Hz.

The force applied to the thrust tool is 1 kN.

The tooling speed is 40 m / h.

Tooling time is 0.025 hours.

B / Move the tool from below.

The energy of one invention is 50 kJ. The frequency of discharges is 1 Hz. The number of steps is 6.

The rest of the data are listed in the table below.

Table 1

Step number The pilot's diameter for a given depth in m Step size, in m Number of discharges per step Time to form a stretch from the pilot in one, step into hours 0 0.3 0.13 3 8.3 x 10 · 1 0.33 0.14 4 1.1 x 10 ³ 2 0.36 0.16 5 1.4 x 10 ³ 3 0.4 0.17 7 1.94 x 10 ³ 4 0.44 0.19 11 3.1 x 10 ³ 5 0.49 0.21 18 5.0 x 10 ³ 6 0.84 31 8.6 x 10 ³

Example 3. Fabrication of a section of a cylindrical pilot with a diameter of 0.4 m, a height of 1 m on a pilot hole with a diameter of 0.13 m and a depth of 1 m, made in a clay base. The pilot is designed as described in Figure 25.

The curing material is a cement sand solution.

The coefficient K of the intensity of accumulation of irreversible deformations in 30 bases is 0.7.

The coefficient χ, depending on the properties of the substrate, is 0.00302. The maximum cross-sectional dimension of the tool is 0.09 m. The flow rate of the cement-sand 35 solution feed is 2.02 m ³ / h.

The energy of one discharge is 50 kJ.

The frequency of discharges is 1 Hz.

The number of steps is 12.

The step size is 0.087 m. 40

The number of discharges in one step is 16.

The time to form the pilot section in one step is 0.0044 hours. The time and formation of a pilot section of 1 m length is 0.062 hours. 45

Although embodiments of the invention are described in the manufacture of cylindrical and conical piles, the invention can be used to make piles of arbitrary shapes, 50 for example, stepped profile pilot / i.e. which consists of several cylindrical sections of different diameters (which are suitable to be introduced into the base, one or more layers of which have sharply reduced strength, and also of cylindrical-conical piles. In addition, the variation of the radii of the pilot in its height can be obtained not only by adjusting the number of discharges or the frequency with which they follow the degree of displacement of the instrument, but also by regulating the energy of the individual discharges. It may also combine the variation of the energy of the discharges with the change in their number or the frequency with which they are produced.

The ability to produce pilots with any profile, depending on the specific construction conditions allows to adjust the bearing capacity of the pilot during its construction, depending on the physical and mechanical properties of the base. Thanks to the reinforcement and compaction of the base around the pilot, its carrying capacity is increased by 5 to 6 times, compared to that of the piled pilots, which are made by known methods.

The invention also provides for the reduction or, in the case of piles in the base, the exclusion of losses in connection with the drilling of a pilot hole, as well as the elimination of the need to use casing and clay solution,

ie to reduce the number of operations, to shorten the time for pilot construction.

The invention can be used in the construction of pilot foundations in the course of construction and in the reconstruction of buildings and engineering facilities.

Claims (10)

Claims 1. A method of manufacturing a pilot by feeding into the pilot formation zone of solidifying material, characterized in that high voltage electrical discharges are excited thereon when the material (6) is fed into the pilot formation zone, wherein the zone (7) for supplying the material / 6 / and for initiating high-voltage electrical discharges is moved to the depth of the pilot-forming zone by the degree of formation of the pilot body, and the total energy from the high-voltage electrical discharge is determined by the depth of the pilot formation area shall be in direct proportion to the increase in diameter of the relevant section of the pilot formation area to the predetermined pilot diameter at that depth. A method according to claim 1, characterized in that the curing material (6) is fed into the initial borehole (1), which is the pilot formation area. A method according to claim 1, characterized in that the curing material (6) is fed directly to the base, which is the pilot formation area. Method according to Claims 2 or 3, characterized in that in the case of a pilot with a height-varying radius when moving the zone (7) for feeding the material and for initiating the high-voltage electrical discharge, the number of these discharges is modified so that at a certain depth of the pilot area the number of high-voltage electrical discharges is directly dependent on the specified radius of that depth. 5. A method according to claim 2 or 3, characterized in that, in the case of a pilot with a height-varying radius, when moving the zone (7) to feed the material and to initiate high-voltage electrical discharges, the frequency of electric tracing the deflection is modified such that its value at a given depth of the pilot formation zone is in direct proportion to the pilot's given radius at that depth. Method according to claim 2, characterized in that the number η of the high-voltage electrical discharges for a certain depth of the pilot-forming zone is determined by the formula η - exp ^r κ (X ^ vT-rj in which r denotes the given radius of the pilot at a certain depth, in m, y _{o the} radius of the initial drilling hole, in m, W the energy of a high-voltage electric discharge at a certain depth, J, K coefficient of intensity of accumulation of irreversible deformations at the base, χ coefficient depending on the properties based on. Method according to claim 3, characterized in that the area (7) for the material feed and for the excitation of high-voltage electrical discharges is moved to a depth at the base, whereby the number η is the discharges at a certain depth, determined by the formula η - exp ^r ~ x X & y / in which r denotes the specified pilot radius at a certain height in m, W the energy of a high-voltage electrical discharge at a certain depth, m in J., K - intensity factor of accumulation of irreversible deformations at the base, χ coefficient, which depends on the properties of the substrate. A method according to claim 3, characterized in that the material delivery and excitation zone (7) is moved to a depth at the base and, after reaching a depth corresponding to the predetermined height of the pilot, the zone (7) / the feed and excitation of high-voltage electrical discharges is moved upwards, this energy W _(a high-voltage electrical discharge during movement of the zone / 7 / the feed 5 and the excitation of the high-voltage electrical discharges in a downward movement is determined by the ratio d ³ f W, --- β J. '10' 13,12 as d denotes the maximum cross-sectional dimension of the tool, which ensures material feed and excitation, in mm, f - coefficient 15 of strength on the basis of the Protodyakov scale, and the number η of the high-voltage electric voids at a given depth as the zone is moved / 7 / up is determined by the ratio 20 η - exp ^g j o, 5 d) as W denotes the energy of a high-voltage electric voids at a given depth as the zone moves submission of material and excitation of falconry electric discharge upwards, in J., r given radius of the pilot at a given depth, in m, K coefficient of intensity of accumulation of irreversible deformations in the base, χ - coefficient that depends on the properties of the base, d - maximum size of the transverse cross-section of the tool providing the material feed and the excitation of high-voltage electrical discharges, m. A method according to claim 4, characterized in that the zone (7) and the material feed and the excitation of high-voltage electrical discharges are moved by a step Ah determined by the ratio Ah - r '(lb) sin {2arctg [(lb) tg for r'> r 5 and Ah = r '(lb) {2arctg [(lb) tg - | -] J for r' <r as in - means the permissible relative deviation from the specified pilot radius and the predetermined pilot cone angle, and d ', d' the specified pilot radius, respectively, from the previous and subsequent steps. 10. A pilot making tool comprising a pipe (3) for supplying the solidified material, characterized in that an electric arrester with coaxially spaced and electrodes separated from each other (10,11) is mounted at the end of the pipe (3). , the first / 10 / of which is ring-shaped and is mounted on an insulating rod passing therein / 15 /, and the second / 11 / is mounted fixed at the end of that rod / 15 / and is connected to the current-carrying rod / 13 /, located inside the insulation rod (15) and connected to the central core of the coa the sial cable (14), the shielding enclosure of which is connected to the first electrode (10), wherein the diameter of the second electrode (10) is larger than the diameter of the insulating rod (15), the first electrode (10) is fixedly connected with the end of the pipe (3) on which the outlet opening (17) is formed so that the axis of the first electrode (10) is parallel to the axis of the pipe (3) and the distance from the outlet opening (17) of the pipe / 3 / to the second electrode (11) is not less than the value of the inter-electrode gap (16).