DE4446008C2 - Process and plant for compacting a soil using explosive charges - Google Patents

Description

The invention relates to a method and an installation for the compaction of a soil according to claims 1 and 13.

Such drill holes reach under the mirror in the ground existing groundwater, and the explosive charges are under the Groundwater level stuck in the ground and exploding brings. The term "explosive charge" excludes a suitable a firing mechanism, for example a wireless one, from the Ignition to be operated. However, it can also known per se, to the ground surface, in this case the Drilling site, leading wires may be attached, creating a Explosive charge using an electrical signal to explode can be brought.

Soils, especially flat and sloping floors that are made of heaped material, which is often loose and initially has been poured dry, such as in areas for the open-cast mining of, for example, lignite or hard coal, found in land reclamation projects or when building dams which can be formed in practice by their instability a potential danger. A shift, a meltdown or a lowering of such a gently sloping flat floor can occur if several of the following factors occur ten:

• (a) in an unstable soil layer, the groundwater is up to a level of more than about 20% of the total  Layer thickness;
• (b) sudden stress or sudden or persistent vibrations;
• (c) finds the distribution of the particle size of the soil material mainly within a certain critical Area instead and / or the particles have a round, ground shape with a smooth surface or
• (d) the soil has a low bulk density (i.e. the critical tightness index is less than or equal to approx 0.6) with a relatively high porosity.

About the unstable soils for humans described above without risk of displacement, delamination or subsidence The influence of the factors must make it bar and cultivable (a) to (d) on soil stability over a land surface Often reduced many tens to hundreds of square kilometers will.

The risk arising from factor (a) can be reduced by lowering the pore water pressure, which is only possible is when the groundwater level in the ground comes from drainage is discontinued. Such drainage has a continuous nuclear character and is therefore very expensive.

The factor (b) is actually only manageable if the area completely blocked for humans with the unstable floor becomes. The potential risk of displacement, delusion or lowering then remains. The factor (c) can not be influenced.

A permanent solution to the instability problem Soil can be obtained if the properties (d) of the Soil to be changed. A tech known from US-A-2 236 759  nik consists of explosive charges using vertical holes to be brought into the ground below the water table and to the Ex bring plosion. This will improve the soil mechanical properties achieved by the loose structure the particles are removed and a higher density is achieved. Because soil stabilization is often carried out in extensive areas vertical holes are normally drilled in run at regular intervals, after which blasting substances used in the boreholes and detonated will. The optimal distance between adjacent drill holes depends on the effective range of the effect of the explosion from. This range is defined as that of the drilling site measured distance at which half the maximum drop is achieved. The effective range depends on the blasting substance mass, type or type and their position in the ground. For a large soil area to be stabilized, therefore very many holes are drilled.

Because for the introduction of the explosive charges from the surface of the unstable soil itself can be drilled out of an area Security considerations can only be gradually stabilized. This creates safe zones in the immediate vicinity of one Drilling site created. At the moment of the explosion (s) the Drilling rig and the associated staff up to a safe Distance of at least 100 m should not be withdrawn in order not to Risk of being exposed to the victim of subsidence from the explosion (drilling) hole and any material To become ground shifts. The area of the explosion is only accessible again after a day because of the Explosion caused pore water pressure to disappear slowly det. The manufacture of for a large to be stabilized The number of holes required for soil area is therefore very high takes a lot of time.

The object of the invention is the method described above for compacting a soil using explosive charge  to improve conditions so that it is safer, faster and cheaper can be carried out.

This object is achieved by the features specified in claim 1 solved. By drilling in a horizontal direction (what on is already known for completely different applications, for example game from US-A-3 878 903), can be from an area with a stable ground to be worked out so that for the drilling rig and the associated people guarantee safe operating conditions are. The system and the staff do not need one Explosion to be brought to a safe area, causing much time is saved and costs are saved. Instead of the Need to drill a large number of holes vertically tion in accordance with the prior art You can now drill in with a small number of holes be satisfied with the horizontal direction, with the holes overlapping can extend a distance of a few kilometers. Because teren will explode in the borehole Explosive charges generally cannot leak material. The explosive charges can be ignited for one or more Drilling at the same time or in a predetermined time chronological order take place. For example the charges from the end of the borehole towards the borehole detonated with each other with a time delay will.

In a preferred embodiment of the method according to Invention will be in the borehole after drilling a number interconnected, at predetermined intervals explosive charges located from each other are introduced. The verb The explosive charges between one another make it possible to a continuous process of explosive charges into the borehole bring in. The connection between them can be chosen in this way be that for the absorption of compressive forces, tensile forces or is suitable for the absorption of both types of force.  

When connecting to each other for the absorption of pressure suitable (for example a line) or if the Explosive charges evenly distributed on a carrier the explosive charges are preferably from the Drilled hole pushed into the borehole. This can be done by the explosive charges through a hollow used for drilling Boring bar are pushed, after which the boring bar from the Bohr hole is withdrawn before the explosive charges explode to be brought.

If the connections between the explosive charges are suitable are for absorbing tensile forces (for example a cable), the bore is preferably carried out so that the end of the Borehole is on the ground surface so that the Explosive charges in an advantageous manner from the end of the borehole into the Borehole can be drawn by using one for drilling used boring bar is used.

In another preferred embodiment of the method according to the invention, after drilling the borehole through a an explosive charge into the open end of a hollow boring bar Drilled borehole, followed by each subsequent drill Explosive charge the boring bar each over a predetermined Distance is withdrawn.

In order to have minimal implementation losses, drilling is preferred multiple holes from a single location. If you're from one single borehole starting from a transition area at all Drilling holes that are parallel to each other can be done with a small number of holes already the bottom of a large ge be compacted. So at a distance of 30 m in a horizontal direction between two parallel drill holes and with borehole lengths of 1000 m, the soil in an area with a surface area of 60,000 m². For certain The parallel drill holes can also be used one above the other instead of being drilled side by side.  

In another preferred embodiment, one drills from from a single drilling site mainly radial radial drilling holes. This way too it is possible to go through a suitable choice of the location of the explosive charges in the drill holes with a very small number of holes a relative stabilize large area.

In a further advantageous embodiment, in which one so to speak hidden dams in the soil to be stabilized see, you first drill a hole or several holes in a first direction, brings explosive charges in each borehole and detonates the explosive charges, after which one of a drilling site on the soil compacted in this way (one "Dam") one or more boreholes in a second direction drilled at an angle to the first direction. That angle will generally be approximately 90 °.

For soil compaction in an extensive area one preferably proceeds in such a way that from different Bohr make holes in the first direction, the main thing perpendicular to the connecting line between the drilling points, Introduces explosive charges in each borehole and the explosive charge exploding and then from drilling sites on the this compacted soil wells into a second rich tung bores, mainly perpendicular to the first direction. On this way, a regular grid with explosive glass is created in the ground introduced.

A plant for the compaction of a soil comprises a drill device or several drilling devices for drilling a Holes in the ground, means for introducing an explosive charge for the introduction of at least one explosive charge in each drill hole and primer to detonate any explosive charge Such a system is characterized according to the invention records that the drilling device for performing a  controlled horizontal bore is set up and that the Means for introducing explosive charges for the introduction of continuously distributed explosive charges or explosive charges conditions at previously determined intervals they are. In this plant, the advantages of a controlled horizontal drilling technology and the compression technology of a Bo dens with the help of explosive charges to surprising and synergistic table way combined.

The invention is explained with reference to the drawing, in which:

Fig. 1 is a graph showing the relationship between the size of the particles in the soil and the size distribution thereof;

Figure 2 illustrates schematically and in perspective the method of compacting a soil with the aid of explosive charges in accordance with the prior art, ie with the use of vertical bores;

Fig. 3 in the same view as Figure 2 illustrates the working way according to the invention.

FIGS. 4 and 5 a schematic cross section of a floor show in your explosive charges have been introduced by means of horizontal wells;

Fig. 6 is illustrated apparently and in plan view of an implementation form of the method according to the invention;

Figure 7 illustrates schematically and in plan view another embodiment of the method according to the invention;

Fig. 8 illustrates schematically and in plan view still another embodiment of the method according to the invention;

FIGS. 9 and 10 different schematically and in plan view, stages of yet another embodiment of the method according to the invention illustrate;

Fig. 11 shows schematically in cross section a boring bar system for performing the horizontal drilling;

Figure 12 shows the system of the boring bars of Figure 11 in another phase of the drilling process;

FIG. 13 illustrates the introduction of explosive charges in a horizontal wellbore;

Fig. 14 schematically illustrates the introduction of a number of interconnected explosive charges in a borehole and illustrates

Fig. 15 shows schematically and in cross section the introduction of explosive charges in a borehole illu strated.

The same reference numbers refer to you in the different figures distant to the same parts or to parts with the same function.

In the graph of FIG. 1, the diameter of the soil particles, expressed in mm, is given along the horizontal axis and the percentage of the total mass of a soil pattern during sieving is given along the vertical axis. If the soil composition is such that the particle size is in the gray area between the two curves shown in the graph, the soil can be considered unstable.

Fig. 2 illustrates the manner in which explosive charges are introduced into the ground according to the state of the art. Part of the floor is shown here as a rectangular block 2 with a length l, which is, for example, 1500 m, a depth d, which is, for example, 70 mm, and a width b, which is, for example, 30 m. It should be noted that the length l of the block 2 is shown disproportionately small.

The soil contains a lower layer 4 , in which groundwater is present, and an upper layer 6 , in which groundwater is missing. In the given example, 51 vertical holes 8 have been made in the ground from the surface of the soil, the holes 8 extending into the lower layer 4 and therefore down to the groundwater. The boreholes 8 are introduced from the surface of the earth above the unstable ground, and therefore there is a risk of displacements, delays or subsidence during drilling operations. As a result of the instability of the ground, each subsequent borehole 8 can only be drilled after an explosive charge 10 has been introduced into a previous borehole 8 up to below the groundwater level and this has been brought to explo- sion. In this way, the bottom after the lapse of some time is compressed such that the space used for the holes 8 rig can be placed for drilling the next drill hole. 8 The distance between the boreholes 8 is shown disproportionately low in FIG. 2, but probably in relation to the length l of the block 2 .

By performing a single horizontal well, according to Fig. 3, which leads to a borehole 12, the same floor can be compression achieved as with the large number of holes of FIG. 2. After the preparation of the well 12 with the aid of a drilling rig 14 are in Borehole 12 introduced a large number of explosive charges 16 , which can then be detonated at the same time or in a predetermined time sequence. The drilling rig 14 is located in an area with a stable floor with a distance s from an area with an unstable floor, which extends in Fig. 3 on the left side of an area indicated by a dashed line.

In Figs. 4 and 5, a slope 20 is shown, which is adjacent to a See 22. The groundwater level in the bottom of the embankment 29 is indicated by the reference number 24 . The drilling rig 14 is in Fig. 4 in a safe area, indicated by s, up and is in Fig. 5 on a vehicle 26 in the lake 22 , ie also in a safe place. Instead of a vehicle 26 can also be drilled from a natural or artificial island. In the direction indicated by e area in which the soil needs to be compacted, is from the drilling rig 14 is a horizontal bore or a plurality of horizontal Boh performed conclusions which the holes 28 that produce 30, wherein introduced into these holes 28, 30 one after the explosive charges 32 and detonated. The drilling rig 14 does not need to be taken out of operation and / or moved.

In the method shown in FIG. 6 - running in the figure from right to left - holes 42 a, 42 b, 42 c and 42 d have been drilled in succession at drilling points 40 a, 40 b, 40 c and 40 d, in which Explosive charges 44 a, 44 b, 44 c and 44 d have been introduced. The drilling rig 14 is located at 40 e for drilling another hole 42 e. All drilling sites 40 a- 40 e be located in a safe area designated with s with a stable soil at a sufficient distance from an area designated with e with an unstable soil to be compacted. From Fig. 6 shows that with a limited number of parallel horizontal drilling a large area can be sealed ver. The drilling rig 14 needs to be moved to a next location only a few times.

A further method is illustrated in FIG. 7, in which one can be satisfied with an even smaller number of displacements of the drilling rig 14 than with the method illustrated with reference to FIG. 6. From each drilling site 46 a, 46 b and 46 c, several controlled horizontal bores are carried out, three in the given example. From the drilling 46 a are holes 48 a, 50 a and a are introduced, and with explosive charges 54 a equipped 52, from the drilling 46, the holes are b 48 b, 50 b and 52 b inserted and fitted b with explosive charges 54 and from the drilling 46 c, where drilling rig 14 is located at the moment, holes 48 c and 50 c have been made and provided with explosive charges 54 c, while the hole for a hole 52 c is being driven.

Fig. 8 indicates a combination of the methods that have been discussed with reference to FIGS. 6 and 7. From each of the locations 56 a, 56 b, three boreholes 58 a, 60 a, 62 a and 58 b, 60 b, 62 b and 58 c, 60 c, 62 c have been made, into which explosive charges 64 a, 64 b and 64 c have been used. The holes 58 a- 58 c, 60 a- 60 c and 62 a- 62 c run mainly in parallel thanks to the control of the horizontal drilling technology, which ensures a very even distribution of the explosive charges 64 a- 64 c in the unstable soil in the area e can be achieved.

According to FIG. 9, in a first step in the manner already described with reference to FIG. 6, three "dams" are formed by the drilling sites 66 a, 66 b, 66 c in an area e with an unstable soil. At the points where these dams are located, the ground is sufficiently stable after the explosion of explosive charges 68 a, 68 b and 68 c to serve as a new drilling site. Correspondingly, Fig. 10 shows how on the dam brought about by the drilling site 66 a new drilling sites 70 a can be selected, of which new holes can be carried out in two opposite directions for the compaction of the soil next to the dam. In a similar manner, the dams formed by drilling sites 66 b and 66 c form the basis for drilling sites 70 b and 70 c, respectively.

Fig. 11 shows the front part of a hollow control boring bar 80 around which a hollow rinsing boring bar 82 is coaxially attached. It is in a manner known per se for the controlled horizontal drilling technique a liquid flow through the control drill rod 80 to the end and in the opposite direction through the space between the control drill rod 80 and the flushing drill rod 82 for performing a horizontal bore. The control of the hole takes place with the help of a posi tion measuring instrument 84 , which is located in the control boring bar 80 . When the end of the borehole is reached, the control drill rod 80 is withdrawn with the position measuring instrument 84 in the direction of arrow 86 from the drilling rod 82 , as shown in FIG. 12. Then (see Fig. 13) through the drilling rod 82, a line 88 with distributed explosive charges 90 or a carrier with evenly distributed explosive charges is inserted in the direction of arrow 92 , after which the drilling rod 82 in the direction of arrow 94 from the Borehole is removed. The tube 88 with the explosive charges 90 remains in the borehole, the explosive charges 90 , each at an appropriate time, can be detonated.

In Fig. 14 it is shown how, with the aid of a drilling rig 14, a mainly horizontal borehole 96 has been drilled in a bottom 98 in such a way that the end of the borehole 96 is located on the surface of the bottom 98 at a location which is designated by the reference number 100 . When one of the drilling rods used for drilling on the side 100 emerges from the borehole 96 , the end of this borehole is connected to the end of a cable of a line 102 , whereupon explosive charges 104 are fixed at predetermined intervals or in which uniformly distributed explosive charges. The withdrawal of the drill rod from the borehole 96 through the drilling rig 14 is thus used in an advantageous manner to introduce the explosive charges 104 into the borehole.

From that in FIG. 12 situation shown, starting at which the Steuerbohrstange 80 is removed from the Spülbohrstange 82, FIG. 15 as in the Spülbohrstange 82 by means of a fluid 106 under pressure a ausgerü with seals 107 constant explosive charge 108 in the direction arrow 110 is displaced. The explosive charge 108 will eventually come through the open end of the drilling rod 82 in the borehole 96 . The flushing boring bar 82 can then be withdrawn over a predetermined distance in the direction of the arrow 112 , after which it can again be used to deposit an explosive charge 108 in the borehole 96 using a pressure fluid 106 . This procedure can be repeated many times as required, the location of the open end of the drilling rod 82 determining the location of an explosive charge 108 in the borehole 96 .

Claims (16)

1. A method of compacting a soil over a predetermined area to produce a substantially horizontally oriented compaction area, wherein one or more holes are drilled in the soil, at least one explosive charge is used in each borehole and each explosive charge is detonated thereby characterized in that a controlled horizontal drilling technique is used for drilling each hole ( 12 , 28 , 30 , 42 a-e, 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c, 96 ), where in the horizontal borehole ( 12 , 28 , 30 , 42 a-e, 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c, 96 ) lying in an essentially horizontal plane, at predetermined intervals or evenly distributed explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 104 , 108 ). 2. The method according to claim 1, characterized in that in the borehole ( 12 , 28 , 30 , 42 a-e, 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c, 96 ) after drilling a number among themselves connected, at predetermined intervals from each other explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 104 , 108 ) is introduced. 3. The method according to claim 1 or 2, characterized in that the explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 108 ) from the drilling site into the borehole ( 12 , 28 , 30 , 42 ae , 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c). 4. The method according to claim 3, characterized in that the explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 108 ) are pushed through a hollow boring bar ( 80 ) used for drilling, after which the boring bar ( 80 ) is withdrawn from the borehole ( 12 , 28 , 30 , 42 a-e, 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c). 5. The method according to claim 2, characterized in that the end of the borehole ( 96 ) is on the ground surface and that the explosive charges ( 104 ) are drawn from the borehole end into the borehole ( 96 ). 6. The method according to claim 5, characterized in that the explosive charges ( 108 ) by a drill rod used for drilling ( 82 ) hen pulling it back into the borehole ( 96 ) are pulled. 7. The method according to claim 1, characterized in that after drilling the borehole ( 96 ) through an open end of a hollow boring bar ( 82 ) in the borehole ( 96 ), an explosive charge ( 108 ) is deposited, after which, before depositing each subsequent explosive charge ( 108 ) the drill rod ( 82 ) is pulled back by a predetermined distance. 8. The method according to any one of the preceding claims, characterized in that from one drilling site ( 40 a-c, 46 a-c, 56 a-c, 66 a-c, 70 a-c) several boreholes ( 12 , 28 , 30 , 42 a-e, 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c) are drilled. 9. The method according to claim 8, characterized in that from a drilling point ( 56 a-c) going out to a transition area mainly zueinan parallel holes ( 58 a-c) are drilled. 10. The method according to claim 8, characterized in that from a drilling point ( 46 a-c) mainly radial holes ( 48 a-c) are drilled. 11. The method according to claim 1 or 8, characterized in that first a borehole or a plurality of boreholes are drilled in a first direction, explosive charges are introduced into each borehole and the explosive charges ( 68 a-c) are brought to explode and that thereafter from a drilling site ( 70 ac ) a hole or several holes drilled in a second direction at a certain angle to the first direction on the soil compacted there. 12. The method according to claim 11, characterized in that from different drilling sites Drill holes in the first direction mainly vertical drilled to the connecting line between the drilling sites, Explosive charges placed in each borehole and the blasting charges are detonated and then by Drilling points on the soil compacted in this way holes in the second direction mainly perpendicular to the in the first direction. 13. Plant for carrying out the method according to one of the preceding claims, which includes a drilling device or a plurality of drilling devices for drilling a borehole in the ground, introduction means for explosive charges for the introduction of at least one explosive charge in each borehole and ignition means for each Bringing up explosive charge, characterized in that the drilling device ( 14 ) for carrying out a controlled horizontal drilling and in that the means for introducing the explosive charges for introducing uniformly distributed explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 ac, 68 a-c, 90 , 104 , 108 ) or explosive charges are formed at mutually predetermined intervals. 14. Installation according to claim 13, characterized in that the means for introducing explosive charges a system of interconnected explosive charges located at predetermined intervals from one another ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 104 , 108 ), the system being designed to be inserted into the borehole ( 12 , 28 , 30 , 42 a-e, 48 a-c, 50 a-c, 52 a-c, 58 a-c, 60 a-c, 62 a-c, 96 ). 15. Plant according to claim 14, characterized in that the explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 104 , 108 ) have been introduced in a line or tube ( 82 ). 16. Plant according to claim 14, characterized in that the explosive charges ( 16 , 32 , 44 a-d, 54 a-c, 64 a-c, 68 a-c, 90 , 104 , 108 ) are interconnected by means of a flexible cable ( 102 ).