FI96793C - Procedures and means for reinforcing soil - Google Patents

Description

96793

Method and instrument for land consolidation Förfarande och medel för förstärkning av jord

The invention relates to a method for reinforcing the soil, in which method a stabilizing or reinforcing additive is introduced into the soil, which is mixed into the soil to form a reinforced zone. In particular, the invention relates to a method of reinforcing soil, in which a rotating, shear-shaped cultivator arranged at the ground, at the lower end of a substantially vertical arm structure arranged on the ground above the area to be reinforced is used to cultivate the soil, in which case a reinforcing additive is actively mixed with soil. to form a reinforced zone behind the modifier in a substantially horizontal direction. The invention further relates to means for carrying out the method according to the invention, the means comprising a pulling strap projecting into the ground and advancing substantially in the direction of the ground, the lower part of which has a movable softening device, i.e. a modifier, for forming a shaped hoop on the ground.

A method of reinforcing the soil, known as pillar stabilization, is known from earthmoving technology, which is carried out by pushing a rotary cultivator at the end of an arm down from the ground. When the cultivator has reached a sufficient depth for the structure, the device is pulled back to the ground. The arm of the device is hollow in structure, and in connection with pulling up, reinforcing material is pumped out through the arm, which is mixed by the rotary cultivator with the soil in the vicinity of the cultivator. As the cultivator is pulled up, a vertical plot is thus created in which a reinforcing material is mixed with the soil. This plot will, at the latest as the reinforcement material hardens, form a stronger structure than the surrounding ground.

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Vertical reinforced plot structures such as those described above have been commonly used to stabilize the ground and, for example, to form temporary construction site walls, road and yard bases and the like, as well as to strengthen the base ground, especially in the case of poorly bearing soils.

The disadvantage of the known method has been that it has not been possible to use it with reasonable material and labor costs in applications where reinforcement is required specifically in the horizontal direction, because the cultivator protruding from the ground leaves a vertical groove. It has been possible to push to some extent in an inclined direction, but in this case the strength requirements and energy requirements of the equipment have greatly increased. In certain cases, several of the above-mentioned vertical plots may have been formed side by side, but in this case the workload and the need for consumption have generally increased disproportionately to the benefit to be obtained, especially if the required reinforcement area has been long and narrow. Thus, the solution has often been that instead of the method described above, a conventional mass exchange has had to be carried out, in which the substantially horizontal soil layer in need of reinforcement or stabilization has been excavated or otherwise removed, replaced by a material with more suitable properties. On the other hand, this has also required a large amount of work, while at the same time having to take care of the disposal of essentially unusable soil.

However, if it has been desired to use the stabilization technique described above, a considerable amount of soil has to be stabilized in practice, in which stabilization would be practically unnecessary, since it has been difficult to apply reinforcement to a specific location according to a known method.

Another essential disadvantage of the known stabilization method is that it always has to use two separate working steps, in which case in the first step the cultivator is only pushed down to the starting depth, from where it must be pulled up as the actual mixing progresses.

Thus, despite the above-mentioned solutions, there is still a need to strengthen the ground, especially to bind the sliding surfaces of soft soils and to prevent ramp build-up and other fractures, in which case the most ideal reinforcement direction would often be horizontal. However, in order for such reinforcement to be competitive with other solutions, the reinforcement must be carried out in such a way that it only applies to the ground layer where the sliding surface of the ground or the rupture of the ground could be calculated to be caused by the load.

Of the prior art, Finnish Patent No. 88816 is further mentioned, which discloses a method for installing pipes or the like on the ground and further a pulling device for pulling a pipe or the like on an above-ground means by means of a device moving above the ground. The traction device then has a traction pulling projecting into the ground, the lower part of which has fastening means for fastening the traction tip of the elongate body. It further has a movable softener device to form a shaped, substantially tubular groove in front of the body to be pulled into the ground. The traction device is caused to move along the mounting groove, whereby the traction sheave with the plasticizers connected to it pulls the body directly or indirectly connected to the shroud into a substantially tubular pre-cushioned groove.

In order to solve the presented reinforcement problem and to eliminate said shortcomings, a method according to the invention has been developed, the features of which appear from the appended claims. Thus, it is known that the additive is fed in the vicinity of the cultivator from outside the cultivator and that the reinforced plot structure is formed to leave behind the cultivator by advancing the vertical arm structure with its modifiers at its lower end by means of a device above said soil.

Thus, the soil modifying means, i.e. the cultivator, is made to travel below the ground in the desired, substantially substantially horizontal direction, whereby the reinforcing additive is brought into contact with this cultivator and mixed with the cultivator's operating range so that the cultivated hollow is substantially horizontally extending reinforced plot structure. The device according to the invention is characterized in that the device has means for feeding a reinforcing additive in the vicinity of the modifier so that the modifier provides a plot-like zone for mixing the soil and the additive.

The development of the technique according to the invention is based on the realization that the device disclosed in Finnish patent no. 88816 can be modified with some structural modifications as described above, which can be pulled quite easily and precisely in the desired, especially substantially horizontal direction in the soil where stabilization may be possible. Thus, the provision of the basic device itself essentially requires an additive supply to be provided in connection with the plasticizer attached to the traction sheave according to said patent, whereby the modifier itself is arranged differently from said patent so that the modifier is preferably located behind the traction sheave. In another embodiment, the supply of reinforcing agent is again arranged substantially through the center of the modifier, whereby the modifier can operate even in front of the traction sheave.

The invention will now be described in more detail with reference to the accompanying drawings, in which

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5 96793 Fig. 1 shows an overview of a basic arrangement according to an embodiment of the invention, Fig. 2 schematically shows an embodiment of the method according to the invention, Figs. 3a. ..3e show sections of different horizontal plot structures formed according to the method of the invention, Fig. 4 shows a further developed embodiment of the invention, in which the movement of the cultivator in different positions is indicated by a broken line, Fig. 5 shows an overview of 6 shows a section of a substantially pool-like reinforcement zone formed by means of the device according to Fig. 4.

Referring to Figure 1 of the method comprises that the soil below the ground level 1 2 is inserted in the direction of the arrow progressive scrambler 3, which höllentäen edit soil the soil along the device moves forward. The cultivator thus leaves a trail of generally cultivated soil, which in three dimensions extends in the soil 2 exactly following the substantially horizontal hollow 4 of the cultivator, whereby the soil outside the working dimension of the cultivator 3 remains substantially unchanged. According to the invention, an additive is now fed to the cultivator 3 at the same time, having the property that, when mixed with the loosened soil in the hollow 4, it forms a ground-extending plot structure 8 of different strength, usually greater than that of the surrounding soil 2. The additive per se can be any known stabilizer, such as, for example, cement, quicklime, bentonite or the like. Preferably, a waste product from another industry, such as fly ash or gypsum, is used for this purpose. Again, in the most demanding 6 96793 objects, substances such as polymerizable plastics and, correspondingly, the additives required for their curing can be used.

In the embodiment according to Figure 1, the modifier 3 consists, for example, of an actively rotating plasticizer with blades 5 known from the above-mentioned patent application, which is driven, for example, by an electrically or hydraulically operated motor 6. The modifier 3 can of course consist of other types of device to mix the additive taken in its vicinity with the soil at its vane 4. The word modifier is to be understood more broadly as any set of equipment which suitably cuts the ground and is at least capable of mixing an additive into it. Thus, according to Fig. 4, the soil-cutting portion of the cultivator 3 and the additive-soil mixing portion may also consist of different devices so that e.g. the soil is cut by a cutter 3a in front of the traction sheave 11 and the additive is mixed by a separate shaping device 3b behind it, which shaping device 3b may even consist of a separate means. In loose soils, on the other hand, mere mixing without a pre-cutting operation is often sufficient.

In the vicinity of the cultivator 3, suitably immediately in front of it or e.g. at its center, an additive is now fed along the pipe 7, which mixes with the cultivator's loosened and cultivated soil, leaving the soil and the additive mixed substantially in place behind the cultivator. the selected reinforcing additive is fed in such a way that the additive is either in powder form, in which case compressed air is suitably used as the supply force, or in fluid form, in which case the feed device is suitably another type of pump.

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Usually, due to the specific moisture of the soil or the liquid or similar fluid fed together with the additive, the additive hardens and binds the mixed soil, forming a horizontally extending rod-like plot structure 8 with a central axis extending exactly in the hub 4 where the cultivator 3 has moved. Depending on the quality of the soil 2, the efficiency of the cultivator 3, the quality of the feed additive, the feed pressure and the propagation speed, the radial dimension of the reinforcing plot structure 8 may vary. scrambler. Figure 4 shows separately how the operating dimension of the modifier can be extended to increase the effective cross-section.

The solution according to Figure 1 has a modifier 3 itself and an additive supply pipe 7 and feed means, generally indicated by reference numeral 18. The cultivator 3 is attached to a traction sheave 11 attached to the boom 10 of a conventional excavator 9, the sharp front edge of which easily passes in weak soil 2, which on the other hand is generally of such quality that horizontal stabilization is specifically necessary.

Especially in more difficult work sites, it may be advantageous for the reinforced plot structure 8 formed on the ground itself to be further reinforced itself for higher shear or tensile forces. In this respect, we refer to a Finnish co-pending application entitled "Method for Improving Earth Strengthening", which is presented here, and the features and technical descriptions presented are thus also considered part of this application.

A great advantage of the method according to the invention compared to the methods known so far is that the reinforced plot structure can be easily placed exactly at the position 8 96793 and in the direction given by the soil survey. Thus, it is expedient for the position and exact direction of travel of the modifier and the additive feed to be determined in advance, the apparatus preferably being provided with an automatic data processing control device for guiding the tip of the traction sheave exactly as desired both laterally and in height.

In some difficult cases, especially in harder soils, it may be appropriate to facilitate the passage of the traction sheave by pulling it with a pre-installed traction cable. In a particular embodiment, the entire modifier can be fitted without an excavator or similar drawbar directly after the elongate drawer, the feed of the additive being suitably arranged via a hollow tubular drawer.

Figure 2 shows a special embodiment of the invention, in which the stabilization is carried out as arcuate lines 8 extending back from the ground 1 through the soil 2 to the ground 1, which can be further supplemented by transverse lines 8a for building a support network on the ground. It is further generally shown in the figure that the modifier 3 itself can also be, for example, a suitably cutting means rotating about a vertical axis.

Figures 3a ... 3e show cross-sections of different plot structures according to the invention. Fig. 3a thus shows a conventional simple plot structure with a substantially circular cross-section, in addition to which a reinforcing web 13 according to the above-mentioned co-pending patent application is shown. The shape according to Fig. 3a can be formed by a shaper 3 whose rotational movement takes place substantially in the direction of travel. The cross-section according to Fig. 3b can again be formed, e.g. by means of the device shown in Fig. 2, so that the modifier 3 rotates substantially

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9 96793 around the vertical axis. The plurality of plot structures according to the invention can advantageously be formed side by side and / or on top of each other, whereby a reinforced wall-shaped plot structure is provided, which functions e.g. as a conventional tongue-wall in connection with ditches or the like. To achieve this, one embodiment comprises a plurality of modifiers 3 which are substantially overlapping but suitably interleaved and / or displaced somewhat in the direction of travel and / or laterally.

A reinforcement pattern formed by the above-mentioned embodiment is shown in Fig. 3c. Fig. 3d shows how parallel plot structures can be used to form plot structure bundles to achieve higher strength, despite the fact that instead of a large cultivator with a larger cross section, a smaller cultivator providing a smaller modified plot would have to be used. forms reinforcements of almost arbitrary dimension, the position of which can be precisely determined as required. Figure 3e thus shows how, for example, the edges of an elongate trench or the like can be supported by means of reinforcement of a certain shape.

In the further developed device according to Fig. 4, the modifier is suitably arranged to operate at the end of the modifier arm 12 articulated to the lower end of the traction sheave 11. At the end of the cultivator arm 12 there is a cultivator means itself with drive devices 6 and reinforcement material feeders (not shown separately). The arrangement according to Figure 4 may then comprise the supply of additive substantially through the center of the modifier, whereby the modifier can also operate in front of the traction sheave 11 when viewed in the direction of movement. Fig. 4 also shows, by means of dotted lines, such a modifier structure such that there is a separate cutting means 3a in front of the traction sheave 11 and a separate mixing means 3b behind the traction sheave 11 for mixing the additive into the soil loosened by the cutting means 3a. The other end of the shaping arm 12 suitably has means 13 for turning the arm around the joint 14 to different inclination positions (indicated by a broken line). The turning means 13 is suitably a hydraulic cylinder, a worm gear or other such suitably separately controllable means. Fig. 4 shows by arrows that the entire cultivator assembly can be suitably pivoted about a vertical axis and can be advantageously moved back and forth horizontally, e.g. by means of a telescopic means arranged on the cultivator arm 12, where mixing conditions are improved and the cultivator can be moved separately without soil contamination. or similar transfer means at the same time need to be moved back and forth.

The entire arrangement can preferably still be raised and lowered in a manner known per se. The modifier arm 12 is preferably arranged in such a way that the modifier 3 can also be brought into a substantially vertical position, in which position the arrangement corresponds in function to a device according to the prior art. Vertical movement is achievable in the simplest embodiment by raising and lowering the boom 10, and in a preferred embodiment the towbar 11 itself comprises separate telescopic means (not shown separately) to provide vertical movement of the lower end of the towbar 11.

With the aid of the device shown in Fig. 4, which is precisely and thoughtfully controlled in the three-dimensional direction of movement, the reinforcement zone 8 according to Fig. 5 can be formed in a fairly simple and particularly precisely controllable manner, which may have a wider lid-like "slab structure" 8b. until. If the bearing base 14 is deep, the substantially horizontal

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11 96793 va reinforcement further combines with a separately formed vertical float according to the prior art. The reinforcement zone 8 according to Fig. 5, which in itself can form e.g. the entire foundation of a detached house, is suitably formed by moving the traction sheave 11 in parallel grooves (indicated by dotted lines), thereby moving the modifier assembly itself laterally and / or vertically. to form a cover structure 8b of suitable thickness, wherein the shaper 3 is turned to the vertical position at appropriate intervals and pushed down to form pillars 8c. The trajectory of the modifier is then suitably programmed in the data processing means to determine the exact location of the reinforcement zone 8 and its parts 8b, 8c as desired. As described, it is easy to form deck-like reinforcement zones 8 with a thickness of 1 to 3 m and based on pillar-like vertical lines with a length of several meters. With a specially designed, telescopically arranged modifier holder, the vertical line can be considerably longer.

In connection with Fig. 5, a structure is shown in which the single-plot reinforcement zone 8 extends in the area between the ground surface 1 and the load-bearing base 14 in a substantially horizontal plane. However, it will be clear to a person skilled in the art that with the arrangement according to the invention it is also possible to form reinforcement zones 8 or individual reinforcement lines, the main orientation of which is more or less inclined. As an example, a pool-like reinforcement zone according to Figure 6 is shown, which is available instead of a tongue wall when operating below the groundwater surface 15. In this case, a cup-shaped pool structure 16 reinforced in the ground is first formed by driving the device according to the invention back and forth and approximately laterally displaced laterally. The soil left in the middle of the basin is then excavated. It can be seen from Figure 6 that the pool structure itself consists of a substantially horizontal bottom portion 17 and inclined side portions 18, which, however, are also formed by a substantially horizontally moving device according to the invention 12 96793. If necessary, the bottom 18 of the basin is still separately anchored, e.g. by means of a reinforced vertical float formed in accordance with said parallel application.

Furthermore, a person skilled in the art will appreciate that several horizontal reinforcement zones 8 can be formed one on top of the other, either by moving a single modifier 3 vertically or by arranging a structure where several modifiers 3 are attached to the same drawbar 11, suitably so that each modifier 3 can be moved 11 along the vertical dimension. In another way, the invention is broadly applicable within the scope of the appended claims.

Claims (17)

96793 The patent was claimed by Muke et A method for reinforcing soil, in which a rotating, ground-cutting cultivator (3) arranged at the lower end of a substantially vertical arm structure (11) arranged on the ground (above the area to be reinforced) is used to cultivate the soil. ) introduces a reinforcing additive which is actively mixed with the soil by the modifier (3) to form a reinforced zone behind the modifier (3) substantially horizontally, characterized in that the additive is fed (7) in the vicinity of the modifier (3) from outside the modifier (3). , 8a, 8b) are formed in the pad (4) left behind by the cultivator (3) by moving the vertical arm structure (11) with its cultivators (3) at its lower end in a progressive manner by means of a device (9) above said in the soil (2). Method according to Claim 1, characterized in that the additive is introduced in front of the cultivator in powder form and / or mixed with liquid, and in that the additive is mixed with the soil during rotation and / or vibration of the soil (2) cutting and / or cultivating means (3, 5). Method according to Claim 1 or 2, characterized in that the substantially horizontal trajectory of the cultivator (3) and the additive feed (7) and the three-dimensional position of its hoop are determined and suitably controlled in advance on the basis of soil survey data, preferably such that the cultivator (3) is guided by a substantially fixed structure (10, 11) penetrating the ground (2), which structure is suitably fixed to the device (9) moving on the ground (1). A claim according to any one of claims 1 to 4. . Method according to claim 3, characterized in that one or 96793 more actively rotated softeners, suitably arranged on the traction sheave (11) of the excavator (9), are used as the modifier (3), the speed of movement of which is suitably higher than that of the advancing plasticizer blades ( 5) the natural rate of rise of the screw surface formed. A claim according to any one of claims 1 to 5. . Method according to claim 4, characterized in that the modifier (3) is drawn into the path by means of a pre-set traction means, suitably a traction cable or the like, the additive supply (7) being arranged in connection with the traction cable or via a separate ground (2) protruding member (11). A claim according to any one of claims 1. . Method according to Claim 5, characterized in that a separate means is used as the cultivator (3), which is located behind the means for cutting the soil (2) with respect to the direction of travel of the assembly. A claim according to any one of claims 1 to 7. . 6, characterized in that cement, quicklime, bentonite, fly ash and / or gypsum, or mixtures thereof, or one or more polymerizable plastic materials and suitably a hardener of the plastic material are used as reinforcing additives, the additive preferably being fed by mechanical means, hydraulically methods or pneumatically. Device for reinforcing the ground in the horizontal direction, the device having a projecting (11) protruding tread (11) extending substantially parallel to the ground, the lower part of which has a movable softening device, i.e. a modifier (3, 5) for forming a modified van (4) on the ground, characterized in (7) for feeding a reinforcing additive in the vicinity of the modifier (3, 5) to form a plot-like zone (8, 8a) for mixing the soil and the reinforcing additive. Il 96793 Device according to Claim 8, characterized in that the modifier (3) itself consists of one or more cutting and / or shaping means (3a, 3b), which means are preferably connected to a common means (11) which can be moved below the ground vertically and / or horizontally pivoting and suitably telescopically protruding. Device according to Claim 8 or 9, characterized in that automatic data processing and control means are provided for controlling the position and / or orientation of the modifier (3), i.e. for determining the dimension of the reinforced bead (4) left behind by the modifier (3). Device for applying soil reinforcement to a desired soil layer, the device having a protruding traction sheave (11) with a movable softener device (3) at the bottom, characterized in that the softener device (3) is adapted to operate horizontally and / or vertically, means (7) are provided for supplying the additive to the modified soil (8, 8a, 8b, 8c). Device according to claim 11, characterized in that the softener device (3) is connected to the traction sheave (11) via a joint (14), comprising means (13) for turning the softener (3) to different inclination positions, including horizontal and vertical positions. Device according to Claim 11 or 12, characterized in that the drawbar (11) is arranged on the boom (10) of the excavator (9), which suitably has means for pivoting the cultivator assembly (3, 11) about its vertical axis. Device according to one of Claims 11 to 13, characterized in that it suitably has telescopic means for bringing the modifier (3) back and forth relative to the end of the traction sheave (11). Device according to one of Claims 11 to 14, characterized in that the device comprises data processing and / or control means for controlling the modifier (3) and for determining the exact location of the reinforcement zone (8, 8a, 8b, 8c). A claim according to any one of the preceding claims. . Use of a method according to claim 7 or a device according to claims 8 to 10 or 11 to 15 to form reinforcing zones (8, 8a, 8b, 8c) extending in the horizontal direction, in the horizontal inclination direction or in the vertical direction. Use according to Claim 16, characterized in that a plurality of reinforcement zones (8, 8a, 8b, 8c) are formed side by side to define a uniform reinforcement area. 96793