EP1904716B1 - Underground construction of a pipeline - Google Patents

Description

The invention relates to a method for creating a driven into the ground pipe string from frontally adjacent pipe elements in a soft, stony and / or rocky ground, with a arranged in a press shaft or in an intermediate press station press device acts on the pipe string and the front side in the joints the tubing arranged, fluid-filled expansion elements are used. Furthermore, the invention relates to applications of the method.

The classical laying of pipelines takes place in trenches, where they are laid piece by piece in a bed, sealed and covered again.

In an overbuilt, couped or otherwise as in the upper area difficult terrain offers itself as a known alternative to drive from a gutted shaft a pipe string into the ground. It is configured as straight as possible Sollweg for the pipe string, with any obstacles are avoided in the largest possible radius of curvature.

The pipe string is pressed by successive application of tubular elements in the soil, with a controllable headpiece shows the way. The new pipe elements are lowered into a press shaft and propelled forward with a press device until the next pipe section can be used. The pipe elements have a diameter of up to several meters, a pipe string of pipe elements, for example, 1 to 4 m in diameter can reach a length of 1 to 2 km or more.

In a target shaft, the head of the pipe string can be removed and the necessary terminators and lines are added.

With increasing propulsion length, the required pre-pressing forces increase due to the skin friction of the pipe elements. Depending on the length of the pipe string and the pressing force to be applied intermediate pressing stations or intermediate shafts can be created for other pressing devices, with which the range can be increased accordingly.

The earth material removed from the conveyor head must be discharged in the opposite direction to the usually approximately horizontal pipe jacking, this can be done in a manner known per se with conveyor belts, rubble cars or the like. Furthermore, in the case of appropriate soil, it is possible to produce thin-flow conveyance in closed pipes.

The high propulsive forces must be transmitted as uniformly as possible and without local stress concentrations on the face side from tube element to tube element, which would not be possible in direct contact without damage. It is known to insert the pipe cross section corresponding pressure transmission rings made of wood-based materials.

When press driving the pipe elements are heavily stressed both in the axial and in the radial direction. The prepress forces must overcome the chest resistance and the friction between the pipe jacket and the ground. Directional corrections lead, in addition to an increase of Vorpresskräfte, especially to a non-uniform distribution of the compressive stresses of the pipe end faces and in the pipe element itself. Other effects, such. As constraining forces and earth pressure, stress the tubes in the radial direction.

The international patent application PCT / CH2005 / 000090 describes the propulsion of tubular elements to create an elongated structure in soft, rocky and / or rocky, even monolithic underground. In this case, the driving force, whose eccentricity with respect to the neutral axis and / or the driving direction are determined. Between the individual Pipe elements are used frontally in the joints of the pipe string, fluid-filled expansion elements. In at least one part of the expansion elements distributed over the entire length of the pipe string, the fluid pressure and / or the deformation in a part of the joints is measured. The propulsive force and its eccentricity with respect to the pipe axis are calculated from these parameters and the values are stored and / or compared with stored standard values. According to a variant, the eccentricity is calculated and the values are converted into control commands for the pressing device and / or the individual fluid supply to or the individual fluid outflow from the expansion elements. After creating the pipe string, the elastic expansion elements remain in the joints.

The disclosures DE 3 414 180 A1 . DE 25 05 980 A1 and EP 0 340 658 A also disclose sealing devices for tubular concrete components which serve to create a pipe string driven into the underground.

The inventor has set itself the task of making the method described above more efficient and to expand the scope.

With regard to the method, the object is achieved according to the invention in that the elastic expansion elements are removed from the joints after the construction of the pipe string. Specific and further developing embodiments of the method are the subject of dependent claims.

• zur bleibenden Starrkörperbewegung mindestens eines Rohrelements in seiner Achsrichtung wenigstens einem Dehnelement unter Erhöhung des Drucks zusätzliches Fluid zugeführt wird,
• nach der vorgegebenen Erhöhung der Fugenbreite auf einen vorgegebenen Wert das Fluid des betreffenden Dehnelements abgelassen, und
• das Dehnelement in das Innere des Rohrstrangs entfernt, einer Wiederverwendung zugeführt oder entsorgt wird.

The removal of the elastic elements from the joints is done depending on the material, joint width, clamping force, etc. as desired. According to a preferred embodiment of the invention, elastic expansion elements, starting from at least one front end of the tubing string and / or an intermediate pressing station, are removed individually or in groups, step by step

• is supplied to the permanent rigid body movement of at least one tubular element in its axial direction at least one expansion element under increasing the pressure of additional fluid,
• after the predetermined increase in the joint width to a predetermined value, the fluid of the respective expansion element is discharged, and
• the expansion element is removed into the interior of the pipe string, fed for reuse or disposed of.

The stepwise removal of the expansion elements can, as mentioned above, take place with respect to the pressing direction from the front or from the rear, according to variants also simultaneously from both sides and / or from at least one intermediate pressing station. This beginning of the removal of expansion elements results from the skin friction, which includes the static and sliding friction .. The skin friction is cumulated for all pipe elements at the front end of the pipe string and lowest in the region of the intermediate press station. Where the static friction and sliding friction is comparatively low, two or more expansion elements can in each case cause a joint enlargement by increasing the pressure, again starting from one or both front ends of the pipe string or at least one intermediate press station. This is in itself more efficient than the pressure increase in each case an expansion element, but pushes quickly because of the mentioned static friction and sliding friction.

Due to the displacement of when slightly elastic tube elements, the skin friction must be overcome by the pipe element to the surrounding soil. After the pressure relief of the elastic expansion element "displaced" a displaced pipe element slightly back, but not completely due to the rigid body displacement of the pipe elements against the ground in the original position. If a pressure relief without permanent rigid body displacement of at least one pipe element would take place, the residual force clamped the expansion element, it could not be pulled out of the joint. In the inventive enlargement der.Fugenbreite remains after the pressure relief, a residual force, which allows easy pulling in of the expansion element into the tube interior.

A filled with a fluid, but non-pressure expansion element usually has a circular cross-section of a dependent on different parameters outside diameter D _o of a few centimeters, in practice less than 10 cm. During press driving, the expansion element is compressed to, for example, 20-50% of the original diameter D _o . After the propulsion remains a residual pressure in the expansion element. In the application of the inventive method, the expansion element expands due to the increasing pressure back to suitably 60 - 80%, the original outside diameter D _o , the joint between the adjacent pipe elements is widened accordingly. After relieving the pressure, the expansion element reduces again to 50 - 70% of the original outside diameter D _o , the continuous joint width is dimensioned accordingly.

To remove the expansion elements, the joint width d between the tubular elements driven into the substrate is expediently increased by at least about 30%, preferably by at least about 50%, in particular by at least about 100%, which, as mentioned, is effected by appropriate fluid supply.

The fluid used is preferably a pressure-resistant liquid, but it can optionally also other liquids; such as water, and even gases, such as air, are used.

The expansion elements can in principle assume any geometric shape, but they are at least adapted to the cross-sectional shape of the tubular elements. The most common shapes are ring elements and spirally inserted elements which extend over the end face of the tube elements.

According to a specific embodiment of the invention, for example, annular expansion elements are subdivided sectorally along the circumference. In this case, pressure increase can be brought about in all sectors, but also in only a part of the sectors. In principle, a pressure increase in a single sector.

The inventive method has the primary advantage that the expansion elements can be easily and undamaged drawn into the tube interior. Even this alone has a considerable economic and environmental value, designed for extremely strong pressure load expansion elements must not be purchased after use, but can be reused. Damaged expansion elements can be repaired or disposed of properly.

In general, all expansion elements are removed from the joints, but it is also a targeted removal of certain expansion elements possible.

• Die Fugen können mit einem fliessfähigen, erhärtenden, druckfesten Baumaterial gefüllt und damit die Stabilität des Rohrstrangs erhöht werden, beispielsweise mit Mörtel.
• Die Fugen können mit einem elastischen Material, beispielsweise Silikon, gefüllt werden, was den Rohrstrang bei bleibender Elastizität abdichtet. Das elastische Material kann beutel- oder schlauchförmig ausgebildet sein und mit einem Fluid, d.h. einer Flüssigkeit oder einem Gas, gefüllt sein. Der dazu eingesetzte Schlauch oder Beutel ist wesentlich billiger als das vorher entfernte Dehnelement.
• Erreicht der Rohrstrang nicht die vorgegebene Länge, kann diese justiert werden, indem eine vorgegebene Anzahl von Fugen verbreitert wird.
• Die Fugen eines Rohrstrangs mit entferntem Dehnelement können z.B. für eine Unterfangung oder einen Baugrubenabschluss mit einem fliessfähigen, aushärtenden Material gefüllt werden, insbesondere Mörtel. Zusammen mit einer anschliessend angelegten externen Vorspannung können diese Rohrträger nach dem Vortreiben im Untergrund wie Balken von grosser Tragfähigkeit und kontrollierbaren mechanischen Eigenschaften eingesetzt werden.

The method according to the invention can also be applied by opening a secondary use in various ways:

• The joints can be filled with a flowable, hardening, pressure-resistant construction material and thus the stability of the pipe string can be increased, for example with mortar.
• The joints can be filled with an elastic material, such as silicone, which seals the pipe string with lasting elasticity. The elastic material may be bag-shaped or tubular and be filled with a fluid, ie a liquid or a gas. The tube or bag used for this is much cheaper than the previously removed expansion element.
• If the pipe string does not reach the specified length, it can be adjusted by widening a predetermined number of joints.
• The joints of a pipe string with removed expansion element can be filled, for example, for an underpinning or a construction pit with a flowable, hardening material, in particular mortar. Together with a subsequently applied external preload, these pipe supports can after driving in the Substrate such as beams of great bearing capacity and controllable mechanical properties are used.

• Fig. 1 einen Vertikalschnitt durch einen Pressschacht mit einem Rohrstrang,
• Fig. 2 den Verlauf des Rohrstrangs unterhalb eines Strassenabschnitts,
• Fig. 3 einen Axialschnitt durch zwei stirnseitig aneinander liegende Rohrelemente
• Fig. 4 ein Detail einer Stossverbindung zweier Rohrelemente mit einer Mess- und Fülleinrichtung, gemäss IV von Fig. 3, und
• Fig. 5 einen Rohrstrang mit n Elementen vier verschiedene Stufen der Entfernung der Dehnelemente.

The invention will be explained in more detail with reference to embodiments shown in the drawing, which are also the subject of dependent claims. They show schematically:

• Fig. 1 a vertical section through a press shaft with a pipe string,
• Fig. 2 the course of the pipe string below a road section,
• Fig. 3 an axial section through two frontally adjacent tubular elements
• Fig. 4 a detail of a joint connection of two pipe elements with a measuring and filling device, according to IV of Fig. 3 , and
• Fig. 5 a pipe string with n elements four different stages of removal of the expansion elements.

In the subsoil 10, from the soft earth to the monolithic rock, starting from a press shaft 12, a pipe string 14 is propelled, which extends in a few meters depth approximately parallel to the earth surface 16. The individual pipe elements 18 are lowered by means of a lifting device 20 in the press shaft 12.

An abutment 22 supporting pressing device 24 is aligned with the tubing string 14. In the present case, these are hydraulic presses, but it is also possible to use pneumatic presses or lifting spindles. A pressure ring 26 presses the end face on the rearmost tubular element 18 and pushes the entire pipe string 14 in the feed direction 28 by the length I of a tubular element 18 forward. Then the pressure ring 26 is withdrawn, a new tubular element 18 is lowered and with the interposition of an expansion element 44 (FIG. Fig. 3 ) precisely. Then the insertion takes place by a further tube length I.

Simultaneously with the pressing of the tubing string 18 in the substrate 10, the displaced soil is reduced by a head piece 30 in a conventional manner. This is done for example by a built-in excavator 32, a milling machine or other known in tunnel or mining equipment. With a transport device, not shown, the removed soil 34 in the direction of the press shaft 24, that is opposite to the propulsion direction 28, promoted.

The propulsion takes place as mentioned step by step. One step involves the insertion of a tubular element 18, the feed of the tubing string 14 by the length I of the tubular element 18 in the feed direction 28. The feed force 40 (FIG. Fig. 3 ) is applied via the expansion elements 44 (shown below) ( Fig. 3 ) transmitted from pipe element to pipe element 18.

As mentioned, the tubing string 14 generally runs approximately parallel to the earth's surface 16. The tubing string 14 may, however, also run at any other angle.

For various reasons, eccentricities may occur during the advancement of a pipe string 18, as shown in FIG Fig. 3 is shown in detail.

The headpiece 30 usually has a locating device 36, so the situation can be determined at any time and any necessary corrections are made. Next can be precisely excavated at a possibly necessary repair or replacement of the head piece 30, an auxiliary shaft.

In Fig. 2 is an S-piece of a road 38 with underlying pipe string 14 indicated. The pipe string 14 is performed with the largest possible bending radius through the S-piece, the projected pipe path runs as straight as possible. By measuring and process control according to the present invention, the Pipe string 14 follow the projected pipe path as far as possible.

Fig. 3 shows the end faces 42 of two tubular elements 18 in the rest position, on which a driving force has been exerted. The two end faces 42 of the tubular elements 18 are connected at the end by an expansion element 44 designed as a hollow profile. The cavity of the expansion element 44 is filled with a pressure-resistant fluid 46, the pressure p is in the present case about 80 bar. The distance d between the end faces forming the joint 70 is 18 mm.

The connecting region of the two tubular elements 18 is covered with a sleeve 48, which has a guiding and sealing function. The sealing function is supported by an inserted O-ring 50.

Preferably, all the cavities of the expansion elements 44 are connected over the entire pipe string 14 via a pressure line 56, as in Fig. 4 will be shown. This pressure line 56 is connected via a filling cock 58 with the fitting 60 of each connected expansion element 54. With a lever 62, the filler cock 58 can be opened. The fitting 60 is also equipped with a pressure gauge 64 and a vent cock 66 through which excess fluid 46 can be discharged into the interior of the tubing string 14. Across from Fig. 3 is the pressure p in the expansion element 44 according to Fig. 4 greatly increased, whereby the expansion element 44 has assumed a somewhat less flattened, almost circular cross-section. Accordingly, the left tubular member 18 is displaced in the direction of the arrow 52, the joint 70 has now assumed a predetermined increased width d '.

• I. Der Rohrstrang 14 mit n Rohrelementen 18 ist erstellt, zwischen den einzelnen Rohrelementen 18 ist stirnseitig je ein den Element 44 angeordnet, weiches unter einem Restdruck steht.
• II. Die erste Fuge 70 ist durch Druckerhöhung im ersten Dehnelement 44 auf das gut Doppelte verbreitert worden, das erste Rohrelement 18 ist in Richtung des Pfeils 52 in Richtung des Pressschachts 12 gedrückt worden. Es wird der Moment der Druckentlastung in der Fuge 70 und der Entnahme des Dehnelements 44 dargestellt.
• III. Der Druck des Fluids im Dehnelement 44 der zweiten Fuge 70 in der ehemaligen Vorschubrichtung 28 ist entsprechend II bezüglich der ersten Fuge erheblich erhöht worden, wodurch das zweite Rohrelement 18 in Richtung des Pfeils 52 bzw. des Pressschachts 12 verschoben wird, bis der Abstand d" erreicht ist. Die beiden Abstände d und d" sind weitgehend gleich.
• IV. Dieser Vorgang wird noch (n-3) mal wiederholt, bis alle Dehnelemente 44 entfernt sind.

Fig. 5 shows a pipe string 14 between a press shaft 12 and an end shaft 12 '. The tubing string 14 is presently about 1.5 km long. Not shown are any, the press shaft 12 corresponding intermediate press stations whose position is inter alia by the maximum pressing force of Pressing device 24 ( Fig. 1 ).

• I. The tubing string 14 with n tube elements 18 is created, between the individual tube elements 18, one element 44 each is arranged on the front side, which is under a residual pressure.
• II. The first joint 70 has been widened by almost exactly twice the pressure in the first expansion element 44, the first tube element 18 has been pressed in the direction of the arrow 52 in the direction of the press shaft 12. It is the moment of pressure relief in the joint 70 and the removal of the expansion element 44 is shown.
• III. The pressure of the fluid in the expansion element 44 of the second joint 70 in the former feed direction 28 has been considerably increased according to II with respect to the first joint, whereby the second tube member 18 is displaced in the direction of the arrow 52 and the press shaft 12 until the distance d " The two distances d and d "are largely the same.
• IV. This process is repeated (n-3) times until all expander elements 44 are removed.

Optionally, the same process can be carried out from the end shaft 12 'to the press shaft 12. According to another variant, the pressure can be increased simultaneously in two expansion elements 44 until the distance d 'is reached in the two joints concerned, both expansion elements 44 simultaneously relieved and pulled into the pipe interior.

Claims (10)

1. Method of constructing a pipeline (14), which is driven underground (10) and consists of pipe elements (18) bearing against one another at the end faces, in soft, stony and/or rocky ground, wherein a jacking device (24) arranged in a jacking pit (12) or in an intermediate jacking station acts on the pipeline, and fluid-filled elastic expansion elements (44) arranged in the gaps (70) of the pipeline (14) are inserted at the end faces, characterized in that the elastic expansion elements (44) are removed from the gaps (70) after the construction of the pipeline (14).
2. Method according to Claim 1, characterized in that elastic expansion elements (44), starting from at least one end face of the pipeline (14) and/or an intermediate jacking station, are removed individually or in groups by virtue of the fact that

   - for the permanent rigid body movement of at least one pipe element (18) in its axial direction (28), additional fluid (46) is fed to at least one expansion element (44), with the pressure (p) being increased,

   - after the increase in the gap width (d') to a predetermined value, the fluid (46) of the relevant expansion element (44) is drained, and

   - the expansion element (44) is removed into the interior of the pipeline (14), supplied for reuse or disposed of.
3. Method according to Claim 1 or 2, characterized in that the gap width (d) is increased by at least about 30%.
4. Method according to Claim 3, characterized in that the gap width (d) is increased by at least about 50%, in particular by at least about 100%.
5. Method according to one of Claims 1 to 4, characterized in that, starting from at least one end face of the pipeline (14), in each case one or two expansion elements (44) are removed gradually.
6. Method according to one of Claims 1 to 5, characterized in that, in the case of expansion elements (44) subdivided into sectors along the circumference, the pressure (p) in at least some of the sections is increased.
7. Method according to one of Claims 1 to 6, characterized in that the fluid (46) used is an incompressible liquid, preferably water, or a gas, preferably air.
8. Use of the method according to one of Claims 1 to 7 for the adjustable lengthening of the pipeline (14).
9. Use of the method according to one of Claims 1 to 7 for filling the gaps (70) with a free-flowing, curable, pressure-resistant construction material for a pipeline (14) which can be prestressed externally.
10. Use of the method according to one of Claims 1 to 7 for filling the gaps (70) with an elastic material, also with a fluid-filled tube or bag, for a flexible pipeline (14).

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