DE2838363A1 - LIQUID AND PERMEABLE WALL AND METHOD OF MANUFACTURING THE SAME - Google Patents

Description

j CLOSED

The invention relates to a liquid-impermeable wall and a method for producing the same, in particular on foundation walls with liquid-tight joints and on a method for producing such foundations.

Waterproof foundations arranged in the ground have to meet numerous requirements in the construction industry. For example, can Trenches are dug in the ground and filled with concrete to prevent water seeping through or for excavation work without significantly disturbing the geology of the surrounding land. Waterproof constructions are included the production of building foundations is also of considerable importance. Are the trenches or foundation recesses in relatively solid clays or excavated in the rock, the side walls of such trenches are usually strong enough to allow the Can also create trenches with considerable depth with the help of machines. However, these conditions are true does not always occur when the soil is saturated with water and consists of mud, sand and / or gravel.

If you try to dig a deep, narrow trench in a sandy soil saturated with water, you will end up with the When the water level is reached, the movement of the water ring dissolves the ditch the sand and brings the walls and ultimately the entire ditch to collapse. Around a trench of the desired depth To be able to produce, it must ultimately be laid out so broadly in the area of the soil surface that the costs for the later Backfilling has a significant impact on the book.

This problem was in itself already through an excavation process solved, which as a sludge excavation or membrane wall construction can be designated. Here, the trench is filled with a cloud during the excavation process, which from one

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Mixture of bentonite and water consists. As the excavation work progresses, turbidity is constantly added, so that a tough, flexible seal is formed on the inside of the trench and prevents water from flowing through the trench walls. ^{This I 1} XIm formed in this way, together with the pressure of the turbidity behind it, keeps the walls upright and watertight. As the digging continues, the sludge moves to the newly exposed parts of the trench and lets the sealing effect begin there.

Hachdem dug the trench to the desired depth and with Was filled cloudy, the width of the trench occupying metal pipes are lowered into a section and act there as lateral Stops to shield or isolate this section during its subsequent creation. This section then becomes Filled with a water-impermeable material, such as concrete, clay or a mixture of clay, sand and gravel, while at the same time the Slurry is removed from the trench section, preferably for reprocessing and for re-use. The foundation material is then left cure, whereupon the tubes can be removed at both ends without the newly formed wall in the remaining Part of the trench could collapse. After removing the pipes, a new section is made adjacent to the first section educated. For this purpose, a pipe is arranged at a distance from the previous section at the far end of the new section. The new section is then filled with the foundation material, the pulp in it again being removed. After this the new section is sufficiently hardened, further sections can be formed in the same way until finally the desired wall length has been reached. With this method and elaborate excavation equipment, depths of several hundred Reached foot.

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Bentonite - and especially sodium bentonite - has one property which makes it particularly valuable as a means of forming turbidity. When dispersed in water, matrium bentonite adsorbs water / water on the surface of its discs and thus leads to many individual clay discs, each surrounded by a shell of water are. This shell of water gives the bentonite the ability to develop viscosity in the water and so does the trench walls a tough, thin PiIm lining the water permeability decreased.

Although this method produces a noticeable advance over this earlier procedures, but still not completely satisfactory. Especially when pouring a new section of concrete this does not connect seamlessly with the previously cast section. At least in part because of the previous poured section is provided with a layer of the pulp. This creates a potential water passage through the Wall built in, i.e. along the joints of adjacent sections. In some cases the water penetration is so strong that that additional wall sections parallel to the main foundation in the area of the joints are required to allow the passage of the Prevent v / assers from the bumps. There is thus a need for foundations that are inherently watertight, as well as a method for making such foundations.

The object of the invention is thus to provide a liquid-impermeable To create a wall in a liquid-permeable base and a method for producing such a wall. Furthermore, a method for building a liquid-impermeable wall in individual sections with liquid-tight Butt joints between the same are specified. This is supposed to

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additional auxiliary walls can be dispensed with. The procedure is supposed to In addition, it is relatively easy and inexpensive to carry out be. Likewise, "the object of the invention is also to tackle such a wall yourself.

The method according to the invention basically includes the successive one Formation of a number of laterally extending, liquid-impermeable wall sections that are mutually touch at their lateral ends, the removal of wall material on adjacent sides of the borders or interfaces with the formation of recesses that are common to the adjoining sections and that subsequent filling of the recesses with a liquid-sealing material. The sections adjoining each other the interfaces are marked in the vertical direction to the wall by liquid-permeable end parts, at which the sections abut one another essentially and by a recess arranged therebetween, the is filled with the liquid seal to prevent leakage between the end portions.

The invention is particularly advantageous in the field of sludge excavation technology applicable. Here, a substantially vertical trench is dug and filled with a watertight sludge, which is preferably comprises a mixture of a hydroexpandable bentonite and water. Two insulating parts are used in the trench for separation a first section arranged. One of the parts has a detachable guide part located on the section to be insulated Side up. Then a hardenable, water-impermeable wall material is entered into the trench section and the Cloudy removed at the same time. After the wall material so

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is sufficiently hardened that it takes on the lateral contours of the insulating parts, the guide part is removed and when Remove the insulating part and leave it in the trench. After the formation of the first wall section another insulating part is arranged to form a second trench section in the trench, namely on the guide part next to the first section and at a distance from it. By introducing wall material, the same Way, a second wall section is geMLdet, which has a common lateral interface with the first wall part. Here the sludge is in turn displaced from the trench at the same time, and the wall material is allowed to harden.

According to the requirements, further sections are added, until the wall has the desired length. With the exception of the last one, each insulating part has a removable one Provide guide part. The wall obtained, consisting of several sections, is usually not at its interfaces waterproof between sections. In order to make these joints watertight, a hole is made at each interface, whose diameter is dimensioned so that it runs on both sides of the interface in the wall material. Here the in the wall left guide part drilled out. Finally will Bentonite, preferably in pellet form, is introduced into the bore in such an amount that a waterproof beet forms with it the water seeping into the borehole along the interface. The preferred bentonite pellets are diameter of about one cm and consist of a specific bentonite composition that is resistant to contamination. An initial, limited passage of water through the wall is thus considered an integral part of the preferred "method of manufacturing

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position of watertight pushrods used.

Further details, features and advantages of the invention emerge from the following description, the patent claims and based on the schematic drawing. Here show:

Pig. 1 and 2 plan views to illustrate two states or stages in the construction of a floor foundation wall according to the state of the art;

Pig. 3 and 4 are plan views showing two states or stages in the construction of a floor foundation wall according to the invention;

Pig. 5 »6 cross-sections along lines 5-5, 6-6 and 7 and 7-7 of the Pig. 4;

Pig. 8 is a plan view of a floor foundation wall during a construction stage in FIG Connection to the state according to Pig. 4ϊ

Pig. Figure 9 is a cross-section along line 9-9 of Pig. 8th;

Pig. 1o to 13 partial cross sections for illustration successive states in the production of a liquid-tight connection point between one another adjacent areas of the foundation wall along the line 1o-13 - I0-I3 of the Pig. 8 and

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Figure 14 is a partial cross-section taken along line 14-14 of Pig. 8 for illustration the finished connection or joint.

According to Pig. 1 is a first or initial step or state at Construction of a foundation wall or liquid barrier arranged in the ground shown according to the silt burial technique. A trench 2 was dug to the desired depth and at the same time a slurry 4 filled, which has a mixture of bentonite and water. The amount of these two ingredients will be different for each Application generally recommended by the bentonite supplier. The factors that must be taken into account when determining the correct mixing ratio are: Water purity, in particular the calcium, magnesium or salt content, water temperature and chemical composition of the soil. Basically should the slurry or slurry have such a viscosity that the suspension of fine solid particles as trenching progresses is maintained, so that in this way a water loss of the trench in the direction of the surrounding layers to a minimum is reduced and that it can be replaced comparatively easily by a concrete filling.

Insulating components, such as metal pipes 6 and 8, have a sufficient diameter to completely fill the width of the trench and to act as end points at an intermediate trench section 1o. They are lowered into the trench after it is flooded with turbidity. As soon as the state according to FIG. 1 is reached, concrete is poured into the trench part 1o, the sludge located therein being displaced and preferably pumped out and used again. If the concrete is sufficiently sufficient for the wall section

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is hardened, -to maintain its shape without falling into the ditch, the pipes 6 and 8 are removed and another pipe is inserted into the trench, the one with respect to the right end of the section 1o arranged at the distance of a further section is. Then concrete is poured into the space between the section 1o and the new pipe, which in turn displaces the sludge and forming a second section. Further sections are made in the same way with successive, lateral displacement of the pipe and pouring concrete into the section between the location of the new pipe and the existing wall. educated.

Pig. 2 shows the state of the wall when two are completed Sections 1o and 12. A pipe 14 is arranged laterally in the trench, on the right at a distance from section 12 and forms the right boundary or the right end of a third section. Laterally adjacent wall sections 1o and 12 abut one another and are, as a rule, along a curved joint or intersection 16 connected to each other. The exact shape of this interface is determined by the cross-section of the metal pipes. she is usually not waterproof, and water may seep through or flow through from the between the sections occur on the other side of the wall. If this water penetration is too strong, an additional one is used according to the prior art Wall 18 is provided, which is arranged along the first wall in the region of the respective interfaces. To this Sometimes the water passage was encountered.

With the embodiment according to the invention or the method according to the invention, this water penetration problem is solved in a simpler and less complex manner. According to Pig. 3 will be the same tubes 6 and 8 as insulation tubes to form the

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boundaries of the sections as used in the prior art. In the preferred embodiment of the invention, however, there is a Drill guide part 2o arranged detachably on the side of the tube 8, which is adjacent to the distance to be poured. The guide part 2o preferably has a plastic tube that is attached to the tube 8 by means of releasable or breaking clips or a comparatively weak adhesive is arranged. The guide part 2o touches either the outer surface of the pipe 8 or is arranged in the immediate vicinity thereof, so that it is basically arranged vertically ± m trench is, as it is with the pipes 6 and 8 of the pail.

The wall is produced in basically the same way as in the prior art. Gate by removing an insulating tube However, the guide tube arranged on it is first removed from the trench and embedded in the concrete in the area the lateral interface of the section or leave it at a small distance from it. Then a hole or a bore is made drilled in the concrete of each section with such a diameter that this hole extends over the interface extends between the sections. This is where the drill guide part 2o used as a guide. Subsequently, the borehole is at least partially covered with dry, water-expandable Bentonite filled. The bentonite can be used in numerous forms. For example, pellets can be produced under high pressure or beads are formed and dropped into the bore. You can also use chunks of the same size as the bentonite dryer be taken, find use. Furthermore, the bentonite can either be arranged loosely or as a packing in the recess in a cardboard tube, for example, which then decomposes in the bore within a certain time. Independent the shape of the bentonite is an effective liquid

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sealing brought about along similar lines. When used of pellets "is then water entering the bore between adjacent sections by means of the pellets absorbed, causing them to expand and become a slurry or slurry in the hole that seal the joints against any leakage. According to the invention thus becomes an initial partial leakage through the walls used to create a watertight joint.

Pig. Figure 4 shows a wall at an intermediate stage during its construction. Sections 22 and 24 are already filled with concrete, while a third section 26 is still filled with sludge and to its left through the section 24 along the interface 28 is limited. On its right-hand side, it becomes through the insulating or separating tube 3o made of metal and the guide part arranged on it 32 bordered. Section 24 is shown in the state in which the metal pipe forming the right-hand interface is removed from its associated Guide part 34 was removed and removed, the guide part 34 remaining in the concrete in the region of the interface 28. The manufacture of a finished joint is shown between sections 22 and 24. A hole 36 was here in the Interface 38 driven between the two sections, wherein a guide part embedded in the concrete on the right-hand side of section 22 was used as a drilling guide. Then a sufficient amount of bentonite pellets was placed in this bore 36 to form a turbidity 4o which seals against the passage of water. As described above, the sealing effect occurs when water slowly enters the interface or joint 38 Bore 36 seeps in.

FIGS. 5 to 7 show the trench during various construction stages. According to FIG. 5, the trench section 26 is to the right of the iso-

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lierrohr 3o dug relatively deep with respect to its width and then has been filled with the pulp 4 in order to prevent the side walls 42 from collapsing. The Pig. 6 shows section 26 in a more advanced state of construction, namely after it has been isolated and a steel reinforcement cage 44 has been lowered into the sludge and was placed on the bottom of the trench. The Pig. 7 shows the completed section 22 filled with concrete 46. The latter has hardened and set and forms a water-impermeable barrier. The reinforcing steel 47 is thus solid cemented in and contributes to the strength of the structure. A comparison the pig. 5, 6 and 7 shows that the cross-sectional dimensions of the trench are practical during the various stages of construction have remained unchanged.

In the pig. 8 is the wall according to Pig. 4 shown at a slightly more advanced stage; section 26 is filled with concrete. From Pig. 9 shows the metal tube 3o and the drill guide part 32 which form the laterally right-hand boundary of the section 26. The guide part 32 has a plastic pipe with several rings or lugs 48 which are arranged at a distance from one another and support the spatial arrangement of the plastic pipe in the concrete when the pipe 3o is removed. The guide part 32 is fastened in its upper area by means of a band 5o. This tape is removed from the trench before the pipe 3o is lifted out. Other fastening means, such as weak glue or fastening parts with predetermined breaking points, can also be used to arrange the guide part on the pipe. The essential point here is that the guiding part remains in the trench when the pipe is removed. In the embodiment shown, the guide part 32 is arranged at a small distance from the interface of the section which

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is formed by the left half of the outer wall of the tube 3o.

Pig. 1o shows the interface 28 between the sections 24 and 26 after removing the insulating pipes and filling the section 26 with concrete in section. The guide part 32 protrudes from the trench out, parallel to and slightly offset with respect to the left side of the interface 28. In the next step according to FIG Invention, see Pig. 11 is by means of a concrete drill 52 a vertical longitudinal bore drilled over the entire run of the wall. The part 32 is used here as a guide. The drill 52 has a larger diameter than the guiding part 32 and thus overlaps the interface 28, whereby the drilled hole extends into both section 26 and section 24. The diameter of the guide part 22 is preferably about 25 to 38 mm, that of the drill 52 preferably about 100 mm.

By means of the drilling process, a bore 54 is produced which extends over the interface 28 into the two adjacent wall sections extends; see Pig. 12. The interface between successive pairs of sections can thus be viewed as being in a direction transverse to the water flow is characterized along the interface by end portions 56 and 58, see Pig. 8, in which the two wall sections rest against one another, as well as through a middle part having the drilled recess.

Refer to the next step in Pig. 13 is shown, the hole or recess 54 is made with bentonite in the form of pellets 6o filled, which were preferably produced under high pressure and with a diameter of about one cm. A loading

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Preferred bentonite is sodium bentonite, which is essentially a is hydratable montmorillonite clay, the sodium as the predominant, has exchangeable ion. As mentioned above, Sodium bentonite swells in water and is therefore the in Most useful bentonite type in connection with the invention. The bentonite used according to the invention can, however also have other cations, such as magnesium or iron.

The bentonite is preferably composed in the form of a composition resistant to contamination, as it is described in TJS-PS 39 49 56o of the applicant and to which reference is hereby expressly made with regard to the disclosure. The composition described there is against contamination by resistant to such water that has taken up contaminants as it flowed along the interface with the bore 54. The preferred composition or composition according to the cited patent consists essentially of (A) bentonite, (B) a water-soluble dispersant from the group consisting of a water-soluble salt of phosphoric acid, a water-soluble sulfate of the formula ROSO ₅ X, where R is a hydrocarbon with 8 up to 32 carbon atoms and X is a component selected from the group consisting of an alkaline earth metal or ammonium, and a water-soluble salt of leonardit ^ o as (C) a water-soluble polymer of the group consisting of polyacrylic acid, water-soluble salts of polyacrylic acid, hydrolyzed polyacrylonitrile, Polyvinyl acetate, polyvinyl alcohol, copolymers of these substances and a copolymer of acrylic acid and maleic acid; the amount of the water-soluble polymer in this floor sealant composition is 0.1 to 3% by weight 6, the amount of the water-soluble dispersant in the floor sealant composition 0.1 to

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3.0% by weight and the weight ratio of water-soluble dispersant to water-soluble polymer 6: 1-36.

After a borehole has been filled with bentonite pellets, it occurs transversely water seeping into the bore through the walls along the joints between the wall sections and "causes a gradual hydrogenation and swelling of the pellets, FIG. 14 shows a completed joint, "in which a corresponding amount of water has penetrated into the bore 36 and one. Cloudy or slurry with the .Bentonite pellets located there. The slurry forms a liquid-tight intermediate seal and prevents any flow of liquid between the opposing end portions 56 and 58, see FIG. 8, of FIG Interface 38 between sections 22 and 24. The problem of water penetration is thus in an effective and inexpensive manner Wise solved, without the need to push the excavation beyond the limits of the main wall.

A particular embodiment of the invention has been shown and described above. In contrast, there are numerous Modifications and variations are possible without thereby departing from the scope of the invention. For example, instead of a filling of the bores with dry bentonite pellets and subsequent swelling of the pellets and formation of a cloud below Influence of the water penetrating through the joints, a slurry can be premixed and poured into the bores. Various ways of arranging a drill guide can also be taken, with the drill guide also being completely waived and the drilling can only be carried out with the aid of external guide means if the drilling equipment allows this. Finally, the preferred embodiment is based on the

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Creation of a liquid-tight barrier in the ground directed; however, the invention is also "in the manufacture of such barriers applicable in reasons other than earth.

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Claims (1)

DIPL.ING. KLAUS RUPPRECHT Westendstrasse 94 PATENT ADVOCATE - jf - D-6000 FRANKPTTET (MAIN) 1 TELEI ¹ ON (0611) 73 22 44 TELEX 0411 882 datttmI'S. November 1978 KFlU / Yy INACHGEREIGHTI COLLOID CüHPANY ILLINOIS (V.St.ü.) FLÜ33IÜKi £ ITSUNDüRCHL ^ 33iaE WANDUNG UIiD TiSftif'AHtdäÜi FOR MAKING THE SAME PATENT CLAIMS 1.) Liquid-impermeable wall, characterized by a number of essentially vertically arranged wall sections (10, 12, 22, 24, 26), which are made of liquid-tight material and extend laterally, one after the other, with a lateral end of each wall section (10 , 12, 22, 24, 26) forms an interface (16) with a lateral end of the next adjacent wall section (10, 12, 22, 24, 26), and in that each interface (16) extends transversely to the wall, each other has opposite - per se - liquid-permeable end parts (56, 58), on which the respective wall sections (10, 12, 22, 24, 26) essentially rest against one another and through a recess (54) provided between them, which with an opposite 909813/0762 Fluid passage sealing Jrübe is filled, uu hereby a liquid passage between the _Jndt parts (56, 53) to prevent. 2. Wall according to claim 1, characterized in that rekennze refuses that the i'rübe water and bentonite auiVeist. J. Method zvx production of a liquid- permeable wall in a liquid-permeable base, characterized in that that one has a number of laterally extending, liquid-impermeable wall sections with a predetermined depth in the base, wherein the sections are substantially successive, have adjacent, lateral interfaces, that one wall material from adjacent Sides of the interfaces essentially over their entire 'run away and here between the adjacent sections, these common recesses and that these recesses are essentially completely filled with a liquid-tight material and thereby the fluid passage through the wall between adjacent sections prevented. 4. The method according to claim 3> characterized in that there is bentonite mixed with water as the liquid-sealing material 909813/0762 used. 5. The method according to claim 4, characterized in that first dry bentonite, which swells when water is added, is filled into the recess, and that liquid is then allowed to enter the recess for mixing with the bentonite along the interface. 809813/0762