EP0753628A1 - Method and device for the construction of a revetement of natural stones - Google Patents

Abstract

The method involves arranging loose rocks in a stabile construction. Concrete, with its flowability improved by pressure etc., is injected in dosed amounts at distant points into gaps in the construction. This causes rocks, located next to and above each other, to be combined to form compact blocks. The concrete is injected simultaneously at several points. Before this stage, the areas concerned are flushed out. The construction has a top rock layer (12), and layer (14) below it of smaller rock sizes, with a geotextile mesh (16) between the two. The concrete is injected through the mesh at least partially into the lower rock layer.

Description

The invention relates to a method for producing a revetment from rubble stones, in particular as a base and slope protection in hydraulic engineering according to the preamble of claim 1.

In hydraulic engineering, revetments are created to secure soles and embankments and serve to protect against erosion and scouring of the hydraulic structures next to or below. Stones ranging from the density of light rock to heavy slag are used. Because of the limited larger mass of the stones they naturally have a limited positional stability. The limited position stability carries the risk that over time, due to the mobility of the individual stones, the revetment may be dissolved or destroyed. The more or less permanent movement of the individual stones also makes it difficult to colonize and fill the revetment with plants and small organisms. Because of the frequent repairs, the maintenance costs are relatively high.

For the above reasons, it has also become known to clamp such revetments with a suitable material. It is known to apply asphalt or hydraulic binders to the revetment. For use under water, colloidal cement mortar is usually used or mortar stabilized against erosion. The mortar penetrates more or less into the revetment and is intended to connect the individual stones with each other. In one method, the mortar to be installed is tumbled flat over water and, in free fall, reaches the surface of the installed stones through the water. In another known method, mortar is fed via a pump system to a distribution pipe under water, from which the mortar is distributed randomly by hoses freely sliding over the revetment.

It is a feature of both known methods that a relatively large amount of the material remains on the surface of the stones and cannot develop a clamping effect there. In addition, the surface is largely sealed, which is undesirable for hydraulic and ecological reasons.

From MAV 1990 page 8 it has also become known to apply the potting material in punctiform or strip-like fashion to cover layers, so that zones with little potting material are formed. A punctual casting with a diameter of 1 m or a strip-like casting with a width of 1 m is proposed.

Partial sealing is also carried out in the method described last, and a larger amount of concrete that accumulates above the top layer does not contribute to the desired interlocking. Despite the reduced amount of potting, this process is therefore also disadvantageous.

The invention is based on the object of specifying a method for producing a revetment from pouring stones, in particular as a base or slope protection in hydraulic engineering, with which a maximum positional stability of the revetment is obtained with a minimal use of potting material.

This object is achieved by the features of patent claim 1.

In the method according to the invention, mortar is injected under pressure into gaps in the bulk material in such a way that stones lying one above the other and next to one another are clamped into compact blocks. For this purpose, a cement mortar is used, which is on the one hand flowable and penetrates into the respective gaps between the stones when injecting, but on the other hand is not distributed as widely as possible around the injected point, but remains in the injected area like lumps or bubbles. This is achieved with a mortar which develops good flow properties under pressure or shear action, but has a relatively high cohesive force when such action ceases, so that there is an onion-like distribution around the injection point. There is therefore a stapling down to greater depths of the revetment or over the thickness of the revetment in a relatively small width, the width depending on the dose introduced. The amount of mortar distributed on the top is extremely small and preferably almost invisible, which is particularly desirable for ecological reasons.

The blocks produced in the process according to the invention ensure a high positional stability of the revetment and at the same time allow adjustment of the stones in between. Tests have shown that the pull-out force in such blocks is three times higher than the lifting force, which corresponds to the weight of a block.

The positional stability, which is considerably improved in the method according to the invention, ensures that the revetment is populated and occupied by plants and small organisms, such as crabs, fish, fry and the like. A revetment produced by the method according to the invention is distinguished by a high level of durability and low maintenance expenditure. The improved positional stability allows e.g. higher speeds of ships in the water and overall greater resilience.

The type of mortar application can be determined geometrically according to the stress criteria of the revetment.

Naturally, a certain period of time passes between the installation of the revetment and the selective injection of concrete. There is therefore a risk that sediments will settle on or in the revetment, which will adversely affect the adhesive effect when the concrete is injected.

One embodiment of the invention therefore provides that the area in question is rinsed before the concrete is injected. The flushing can be carried out with water that is taken from the water in or next to which the revetment is installed.

With the aid of the method according to the invention, a so-called composite revetment can also be produced with an upper and a lower stone layer, of which the lower stones have a smaller class. A geotextile grid of high tensile strength is placed between the layers, e.g. with a mesh size of 10 x 10 mm. The concrete is now injected in such a way that it is not only distributed to a limited extent in the upper layer, but also penetrates through the geotextile grid into the lower layer, so that the two layers of stone are also clamped together.

For the implementation of the method according to the invention, a device is proposed which has at least one lance which can be connected to a source of liquid concrete via a flexible hose. This source is preferably a concrete pump, which is connected to a mixer / metering device, to which material can be continuously added. The pump can be designed in a known manner as a metering pump to determine the amount of mortar to be installed set for each bracket point. The number of pump strokes per point is therefore a measure of the amount pressed. It can be registered in a bracketing log. The lance is preferably adjustable in height or telescopic. According to a further embodiment of the invention, it is provided with an automatic closure at the lower end. This automatically closes the lance when the supply of concrete is stopped to prevent it from flowing back.

According to one embodiment of the invention, an embodiment is particularly advantageous in which a plurality of lances are arranged in a predetermined grid on a support body and can be connected to the source via a distribution device. The entirety of the lances is lowered onto the revetment in a suitable manner, the distribution device ensuring that a predetermined amount of concrete is injected at the predetermined location simultaneously or successively via the lances. The grid can e.g. be a triangular grid.

In order to facilitate precise metering, a further embodiment of the invention provides that a controllable valve is assigned to each lance, preferably directly on the lance, which in turn is a remote-controllable actuating device having. The controllable valve is preferably mounted very close to the lance in order to prevent the liquid concrete from running on after the valve is closed. The valve, for example a slide, can be actuated by a hydraulic adjusting device which is attached directly to the valve housing. The control takes place in a known manner via a suitable distribution device, which is also preferably attached to the carrier body.

The source, e.g. the concrete pump, is preferably connected to the distribution device via a feed line and a return line, and the valves are connected to the common feed line. This allows the liquid concrete to be pumped in a circle, e.g. by successively opening the individual valves at the desired points. After completion, the material can be easily conveyed out of the line, so that the risk of hardening in the line is avoided. The system described can also be easily rinsed during a break in operation, for example with water, in order to clean lines and valves as well as the lances.

Since the device according to the invention is also used under water According to one embodiment of the invention, it is expedient if the valves, the actuating devices therefor and the control distributor are arranged in a watertight housing.

In order to be able to carry out the clamping according to the method according to the invention with the aid of the device according to the invention as quickly as possible, an embodiment of the invention provides that two support bodies are provided, each of which can be moved along a first guide approximately vertically or parallel to the lances, and the first guides along the second guides can be moved approximately horizontally or approximately perpendicular to the lances and adjustment devices are provided between the carrier bodies and the first guide or between the first and second guides. While one support body is temporarily held stationary at a predetermined location so that concrete is injected selectively via the individual lances, the next body can be moved into the next position in order to subsequently inject selectively via its lances, the first body then in the next working position is moved. It is therefore possible to inject concrete continuously so that large areas of a revetment can be processed within a relatively short time. The carrier bodies are preferably attached to the cantilever arm of a conveyor, for example a crane, which in turn can be moved along a path in order to ensure the desired continuity. According to one embodiment of the invention, the track can be arranged on a floating body, for example a catamaran pontoon, and in turn can be moved parallel to itself. The floating body is preferably constructed symmetrically in order to be able to provide the connection of the feed line at both ends of the floating body. This is particularly advantageous where work is carried out under bridges and the concrete has to be supplied outside the bridge. The supply can take place, for example, from a separate floating body on which all the necessary facilities for producing and conveying the concrete are arranged.

It has already been mentioned that in the method according to the invention it is advantageous to carry out a flushing in the areas in which concrete is injected. For this purpose, a rinsing device can be assigned to the lance or the carrier body according to an embodiment of the invention.

Fig. 1

zeigt einen Schnitt durch einen Teil eines Verbunddeckwerks, das nach dem erfindungsgemäßen Verfahren hergestellt wurde.

Fig. 2

zeigt im Schnitt ein Gerät zur Durchführung des erfindungsgemäßen Verfahrens.

Fig. 3

zeigt die Draufsicht auf das Gerät nach Fig. 2 bei entferntem oberem Teil.

Fig. 4

zeigt schematisch den Betrieb der Vorrichtung nach Fig. 2 und 3 in einem Gewässer.

Fig. 5

zeigt die Draufsicht auf die Darstellung nach Fig. 4.

Fig. 6

zeigt schematisch ein Raster für mehrere Lanzen einer Vorrichtung nach den Fig. 2 und 3.

Fig. 7

zeigt eine Draufsicht auf ein abgewandeltes Gerät zur Durchführung des erfindungsgemäßen Verfahrens.

Fig. 8

zeigt eine komplette Anlage zum Betrieb des Gerätes nach Fig. 7.

Fig. 9

zeigt perspektivisch teilweise aufgeschnitten das Gerät nach Fig. 7.

Fig. 10

zeigt schematisch den Betrieb der Vorrichtung nach Fig. 7 und 8.

The invention is explained in more detail below with reference to drawings.

Fig. 1

shows a section through part of a composite revetment, which was produced by the inventive method.

Fig. 2

shows in section a device for performing the method according to the invention.

Fig. 3

shows the top view of the device of FIG. 2 with the upper part removed.

Fig. 4

shows schematically the operation of the device according to FIGS. 2 and 3 in a body of water.

Fig. 5

shows the top view of the representation according to FIG. 4.

Fig. 6

shows schematically a grid for several lances of a device according to FIGS. 2 and 3.

Fig. 7

shows a plan view of a modified device for performing the method according to the invention.

Fig. 8

shows a complete system for operating the device according to FIG. 7.

Fig. 9

shows the perspective partially cut away the device of FIG. 7.

Fig. 10

shows schematically the operation of the device according to FIGS. 7 and 8.

In Fig. 1 a composite revetment 10 is shown with an upper stone layer 12 e.g. size class II for hydraulic bricks. Below this is another layer 14 of hydraulic blocks of size class I. Between the layers there is a geotextile grid 16 with a mesh size of approximately 10 x 10 mm. A coarse filter layer and a fine filter layer below can be arranged below the lower revetment layer 14.

With the aid of a suitable lance or the like, a metered amount of liquid concrete is injected into gaps between stones of the upper revetment layer 16 under pressure. This is shown at 18 in several places in FIG. In Fig. 1, the points at which concrete is injected are shown relatively close together. In reality, they may be further apart. The concrete used is relatively easy to flow under pressure or when shear forces develop, ie as long as it flows, so that it is in the gaps between the stones can penetrate and spread. However, if it comes to rest, it develops a relatively high viscosity, as a result of which the concrete does not diverge to the side, but remains together as lumps adhering to the stones, as can be seen in FIG. 1. In this way, after the concrete has hardened, individual blocks 20 are formed from stones that are clamped together. The blocks bring about an extraordinarily high positional stability of the revetment, but, on the other hand, enable the stones to be fixed between the blocks 20.

As can also be seen from FIG. 1, the concrete penetrates through the geotextile grid 16 into the lower layer 14, so that a firm bond between the upper and the lower layer is produced, which increases the stability of the entire revetment.

2 and 3, a device 22 is shown, with which concrete can be injected into a revetment at several spaced apart points, as described above with reference to FIG. 1. Lances 26 are attached below a plate 24. The attachment of the lances 26 is not described in detail. Valves 28 are arranged on the plate 24, in each case directly above a lance 26. The valves 28 are driven by hydraulic Actuators 30 operated. The hydraulic actuation devices 30 are controlled via a control distributor 32, which is arranged below a plate 34 which is clamped to the plate 24, namely via tie rods 36. Between the plates 34 there is a casing 38 which defines the space between the plates 24, 34 seals.

A pressure accumulator 40 for the hydraulic actuation of the devices 30 is arranged above the plate 34. The device 22 is suspended from a head 42 and can be pivoted accordingly. The suspension is e.g. on a boom of an excavator or a crane.

From Fig. 3 it appears that ten lances 26 are provided, which are arranged in a predetermined grid. The valves 28 can be connected to a common concrete line, specifically via connecting piece 44 of the valves 28. Concrete can constantly flow under pressure through the line, and the corresponding lance 26 is supplied by a corresponding actuation of a valve 28. The valves 28 are preferably opened one after the other in order to provide the necessary pressure for injecting the concrete. The lances 26 have an automatic closure at the lower end, which closes when there is no concrete underneath Pressure is supplied more. This prevents running on. The actuation of the valves 28 allows a targeted metering of the amount of concrete delivered via the respective lance 26.

4 and 5, a water body 50 is indicated with a bottom 52 and an embankment 54, which are to be provided with a revetment according to FIG. 1. A catamaran pontoon 56 has two parallel tracks 58 that guide a boom 60. On the boom is e.g. a device according to Fig. 2 or 3 performed, as indicated at 22a in Fig. 4. The dotted drawing of the device 22a in FIG. 4 shows that it can be moved along the arm 60. As a result, the device 22a with its lances can be brought to any location on the sole 52 and the slope 54. Before the device 22a is moved, either the boom 60 must be raised completely or the lances can be adjusted in height accordingly, so that the lances can then plunge into corresponding gaps in the revetment at the next location.

6 shows a device 22b corresponding to the device 22 or 22a according to FIGS. 2 to 4 from above, the valves being indicated by circles 28b. One recognizes a hairpin-shaped line 62 with an inlet end 64 and an outlet end 66, which are connected to a concrete feed device, for example a concrete pump. 6 also shows the grid in which the lances 26b are arranged. It is formed by equilateral triangles 68. In FIG. 7, two devices 22c, 22d are shown side by side, which are constructed approximately according to the device 22b or 22 according to FIGS. 6 or 2. The structure is therefore no longer discussed in detail. Guide rails 70, 72 are attached to the top of the devices 22c, 22d and can be moved in guides (not shown) below a plate 74. The shift takes place with the help of hydraulic adjusting drives, not shown. Plate 74 is attached to a boom of a suitable truck, such as a crane or excavator. The devices can be used successively so that the revetment can be clamped continuously. A concrete feed line 62b extends in a loop through both devices 22c, 22d, they are therefore supplied together, for example by a concrete pump.

The operation of the device according to FIG. 7 is indicated in FIG. 10. 10a shows the first device, for example 22c, in the working position and the second, for example 22d, in the rest position. 10b shows the second device in the working position, while repositioning the first device. This can be seen from the new position of the guide rail 72. In FIG. 10c, the first device is again in the working position while the second is being positioned.

8 schematically shows a complete system for clamping a revetment of a slope or a bottom of a body of water according to the method described above. A catamaran pontoon 74 stores a crane runway 76 for a crane 78, which has a boom 80, between the parallel floating bodies. On the boom 80 is approximately the arrangement as shown in Fig. 7. By moving the crane 78 along the path 76, moving the path 76 parallel to itself on the pontoon 74 and by the adjustment options in the device according to FIG. 7, the injection of concrete in the revetment in the manner described above can be done in any way way. A concrete line 82 runs along a long side of the pontoon 74 and has sections 84 and 86 on both transverse sides of the pontoon 74, the ends of which end at a leveling pontoon 88 and 89, respectively. A hinge line 90 connects the concrete line 82 to the crane 76 for supplying the injection device, as described above.

Silos 94 for fly ash and silos 96 for cement are arranged on a further float 92, which can attach to a compensation pontoon 88, 89, which are connected via corresponding lines to a metering device 98, which in turn is connected to a mixer 100. A reservoir 102 for additives is also provided, which is also connected to the mixer 100. Below the mixer is a concrete pump (not shown), which is connected to the concrete line 82 via a line, also not shown. As can be seen, a connection of the concrete pump to both ends of the pontoon 74 is possible. Finally, an operating station 104 is located on the float 92.

The material can be transported in with the aid of a barge 106 and can be filled into the suitable storage vessels on the float 92 with the aid of an excavator 108.

The structure of the device according to FIG. 7 can be seen more clearly in FIG. 9. A positioning bar 110 can be seen, which can be attached to the boom of a crane, for example, as shown in FIG. 8. Guides 112, 114 are attached to the beam 110, on which in turn hydraulic cylinders 116, 118 are attached, the piston rod of which can be connected to a guide rail, for example the guide rails 70, 72 according to FIG. 7, for adjusting the rails in the guides 112, 114 and thus both devices 22e.

On the underside of the guides 112, 114 there is arranged a portal 120 and 122, the supports of which form guides for the plate 124, on which the lances 26e are attached in the manner described above. Posts 128 are attached to the plate 124 at the corners and are connected by a strut 130. The strut extends through the guide of the portal 120 and is actuated with the aid of adjusting cylinders (not shown). This allows the height of the unit comprising plate 124 and lances 26e to be adjusted.

The valves are located on plate 124, but only a few of them are shown, as shown at 28e. The valves are actuated in the manner described above. The guidance of the concrete line 62e corresponds to that of FIG. 7.

With the help of the precautions shown in FIG. 9, the lance arrangements can therefore be displaced relative to one another and adjusted in height in order to carry out the injection in the manner that was explained with reference to FIG. 10.

One or more flushing nozzles (not shown) can also be arranged on the underside of the plate 124, which are connected to a pressurized water line (not shown) in order to generate a flushing jet which flushes the revetment first before the concrete injection takes place .

Claims (21)

Process for the production of a revetment of pouring stones, in particular as a bed or slope protection in hydraulic engineering, in which locally pourable concrete is added to the laid pouring works at intervals to clamp the stones in limited areas, characterized in that an improved flowable under pressure or shear Concrete in a metered amount is injected at certain points and spaced into gaps in the bulkhead under pressure so that stones lying one above the other and next to each other are clamped into compact blocks. A method according to claim 1, characterized by an onion-shaped distribution of the concrete in the blocks. Method according to claim 1 or 2, characterized in that the concrete is injected at several spaced apart points approximately simultaneously. Method according to one of claims 1 to 3, characterized in that the area in question is rinsed before the concrete is injected. Revetment according to one of the methods of claims 1 to 4, characterized in that a geotextile grid (16) is arranged between an upper stone layer (12) and an underlying stone layer (14) with a smaller size class and the concrete in the area of the blocks (20) (18) through the geotextile grid (16) is at least partially injected into the underlying stone layer (14). Revetment according to claim 5, characterized in that the stones of the upper layer (12) correspond to size class II and those of the lower layer (14) correspond to size class I. Revetment according to claim 5 or 6, characterized in that the mesh size of the geotextile grid (16) is approximately 10 x 10 mm. Device for carrying out the method according to one of claims 1 to 4, characterized in that at least one lance (26, 26a to 26e) is provided which can be connected to a source of liquid concrete via a flexible line. Apparatus according to claim 8, characterized in that the lance is made telescopic. Device according to claim 8 or 9, characterized in that the lance (26, 26a to 26e) has an automatic closure at the lower end. Device according to one of claims 8 to 10, characterized in that several lances (26, 26a to 26e) are arranged in a predetermined grid on a supporting body (24, 24a to 24e) and can be connected to the source via a distribution device. Apparatus according to claim 11, characterized in that each lance (26, 26a to 26e) is assigned a controllable valve (28, 28a to 28e), preferably directly on the lance (26, 26a to 26e), which in turn is a remotely controllable actuating device ( 30). Device according to claims 11 and 12, characterized in that the source is connected to the distribution device via a feed line and a return line (62c, 62e) and the valves (28, 28a to 28e) are connected to the common feed line. Device according to claim 12 or 13, characterized in that the valves (28, 28a to 28e), their actuating device (30) and the control distribution device are arranged in a watertight housing. Device according to one of claims 12 to 14, characterized in that the lances (26, 26a to 26e) are attached to a support plate (24, 124) on which the valves (28, 28e) are arranged. Device according to one of claims 11 to 15, characterized in that two support bodies are provided, each of which can be moved along a first guide (120) approximately vertically or parallel to the lances (26e) and the first guide along second guides (112 , 114) can be moved approximately horizontally or approximately perpendicularly to the lances (26e) and adjustment devices (116, 118) are provided between the carrier bodies and the first guide and between the first and second guides. Apparatus according to claim 16, characterized in that the second guides (112, 114) on the cantilever arm (80) of a conveyor, preferably a crane (78), are attached. Apparatus according to claim 17, characterized in that a track (76) which can be moved parallel to itself is arranged on a catamaran pontoon (74) and the conveyor (78) can be moved on the track (76). Apparatus according to claim 18, characterized in that a concrete line (82) is attached to the pontoon (74) and can be connected to the source at both ends of the pontoon (74). Apparatus according to claim 18 or 19, characterized in that on a separate floating body (92) silos (94, 96) for the concrete raw material, a metering device (98), a storage container (102) for additives, a mixing device (100) and a concrete pump are arranged Device according to one of claims 8 to 20, characterized in that a flushing device is assigned to the lance or the carrier body.

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