EP0321645A1 - Joint strip for construction joints - Google Patents

Abstract

Joint strip (1, 101) for the joint area (17) of two adjacent sections (15, 16, 132, 133) of a tunnel support system of cast-in-situ concrete segments, with a perpendicular leg (4, 105, 106) which protects the joints against water which flows to the joint after unforeseen damage to the external plastic seal (11, 131). <IMAGE>

Description

The invention relates to a joint tape for structural joints in tunnel construction, which is welded to the outer seal in the joint area of two adjacent tunnel sections to be created in concrete, in particular with inwardly projecting webs and a tubular expansion part.

Concrete construction is currently the most common type of construction in tunnel construction. The tunnel is concreted in sections. Two methods are used: either the tunnel sections are concreted in a row in succession or a section is left between two sections, so that the first, third, fifth, etc. tunnel section is first made of concrete before the second, fourth , sixth etc. tunnel section is concreted.

Irrespective of this, the external seal at the eruption is laid continuously through the tunnel before the concreting work begins. At least the work on the external sealing precedes the concreting work.

At the joints of the tunnel sections, joints are created that are more or less open depending on the age of the tunnel (shrinkage of the concrete) and concrete temperature. In the joint area, the stress on the external seal is extremely high. There is also a need in this area for sealing and supporting the seal against water pressure and for protecting the face shell. That is why joint tapes have been provided for some time. The Depending on the design, joint tapes are several 100 mm wide and are welded to the external seal in the joint area before the concrete work is carried out. The welding takes place with the release of an expansion part of the joint tape. As a result, this results in two weld seams running parallel to the circumference and parallel to the joint between the joint tape and the external seal. Since the seal covers the entire tunnel cross-section, especially when the water is pressing, the joint tape then runs in a ring on the inside of the outer seal. The two weld seams mentioned in turn then form two parallel weld seam rings.

The joint tape thus reinforces and protects the area of the seal on the joint between two adjacent tunnel sections.

Preferably, the welded joint tape is also provided on the inside with webs that are concreted in and on the one hand hold the joint tape in the concrete and on the other hand bring about an additional seal (partitioning) if the external seal is damaged in an unforeseen manner.

As a rule, each tunnel section is also created section by section. I.e. First, the concrete lining is poured in the area of the tunnel floor, then on the tunnel sides, before the concrete is poured in the ridge area in a final concreting step. In the ridge area there are special problems with the formation of cavities. The formation of cavities is preferably due to trapped air or insufficient filling of the firebox with concrete. Added to this is the shrinkage of the concrete. That is why a lot accumulates in the ridge area light water, which then finds its way into the tunnel via the joint in the event of unforeseen damage to the external seal.

The object of the invention is to eliminate this danger. According to the invention, this is achieved by a leg on the joint tape provided in the ridge area and projecting downward. The vertical leg lies exactly in the joint and can be attached to the formwork created for concreting when concreting. The vertical leg has a length of at least 100 mm and is otherwise only limited by the thickness of the concrete lining.

The vertical leg is preferably provided on one side with webs which are concreted in and thus give sufficient support for the leg in the concrete.

In a further embodiment of the invention, the joint tape is provided with two legs which protrude downwards into the joint. The contact surface of both legs is smooth, while the opposite sides are provided with bars for concreting in.

Such joint tapes are difficult to manufacture in conventional extrusion processes. It is therefore provided in a further embodiment of the invention that the two legs projecting downward in the joint tape production have an angle to the joint tape that is less than 90 degrees. The angle is preferably approximately 60 degrees. Both legs projecting downward then also enclose an angle of approximately 60 degrees between them.

The installation of such joint tapes provides that the legs projecting downwards are bent into the vertical. This takes place in concrete construction in such a way that for the tunnel section to be created first, the associated leg is attached to the formwork provided on the end face by means of a separate nail flap (bottom edge). The formwork is attached between the two band legs. To make it easier to assemble the formwork, the leg that is not used when concreting the first adjacent tunnel section can be bent upwards and provided with a temporary hold there. The hold can be achieved by gluing or weld welding. After completion of the first adjacent concrete section and removal of the formwork, the second leg projecting downwards is placed on the first leg which has already been concreted in. It is advantageous to give this leg support in the vertically downward position on the first leg which has already been concreted in. This is done in the same way as above, ie by welding by glue or by gluing. Bitumen filler is also suitable as an adhesive.

Gluing and stapling is preferably carried out at the lower edge of the legs projecting downwards.

In this position, the next concreting process can follow.

It is also advantageous if the joint tape has a tubular expansion part between the downwardly projecting legs and the remaining joint tape part. Such tubular expansion parts are already provided together in the older proposal, and tubular expansion parts for joint tapes in tunnel construction are also common per se, provided that no downwardly projecting leg is provided, and such expansion parts can be provided with a predetermined crack location according to an older proposal. At the predetermined tear point, the tubular expansion part tears open in the longitudinal direction of the hose in the event of excessive tensile load. However, the predetermined crack location is always provided in the continuous belt level. In addition, the tubular expansion part in the known joint tapes, before being torn open, is also subjected to a very high degree of stretching stress in the part which is not intended to be torn open. After the cracking, the existing tensile forces remain and the tensile forces act solely on the material that is still present.

It is therefore advantageous to attach the predetermined crack location in such a way that of the two tube walls of a tubular expansion part forming the connection between two opposite joint tape parts, only one is initially subjected to tension, which then has the predetermined crack location. After tearing open a flow process should take place according to the invention. The other If necessary, the hose wall should give way while loosening the concrete until the tensile load in the joint tape has been reduced. A reduction towards zero can be advantageous. This is based on the consideration that plastic is subject to a cold deformation under permanent tension, which is synonymous with a considerable reduction in cross-section at the points subject to tensile stress.

In order to enable the flow movement, the tubular expansion part in the area of contact with the tunnel sections is provided with flow slopes. Such an incline, which can also be designed in the form of a rounding, prevents the expansion part from getting caught on concrete edges. Furthermore, it can be advantageous for the flow movement according to the invention if the tubular expansion part is pressed in. Initially, this means an indentation by the legs pointing downwards. The indentation allows the tubular expansion part to yield much more after it is released from the concrete than the previous arrangements without indentation. Optionally, the open cross-section of the tubular expansion part is reduced by 10 to 40% by pressing in. The indentation can be effected very easily with the help of the legs projecting downwards and secured by striking the formwork. After the first definition of a leg on the formwork, the degree of indentation is also largely determined.

The advantageous flow movement while lifting off the concrete in the area of the tubular expansion part is also supported by a pretreated surface of the expansion part. For this purpose, an agent preventing the adhesion of the tubular expansion part to the concrete can be applied to the surface of the tubular expansion part be applied. However, it is also possible to use a plastic with little or negligible adhesive power for the tubular expansion part. Optionally, an additional coating of the tubular expansion part with a non-stick plastic or substitute is also possible.

The breaking point is at the o. B. advantageous embodiments of the invention at the outer location of the tubular expansion part. I.e. the tubular expansion part tears open on the outside with excessive load. This allows the expansion part to yield further without losing its sealing effect.

The predetermined tear point is realized in that the material thickness of the tubular expansion part in the continuous band plane is less than in the remaining area of the tubular expansion part and the lateral joint band parts. When the joint tape profile according to the invention is produced by extrusion, this is achieved by appropriate arrangement of the mandrel forming the interior of the tubular expansion part. I.e. the mandrel is arranged accordingly close to the boundary surface of the tool.

It is also advantageous if the webs provided on the legs projecting downward into the joint collide with radially extending webs in the circumferential direction. Then isolated cavities are created, which are filled in by the concrete of the associated tunnel sections. Incoming water can only flow into the sealed cavities, not out of them.

In a further development of the sealing system according to the invention it is provided that the two downwardly projecting legs are at a distance from one another at their leg ends connected to the expansion part. The arrangement at a distance ensures that a different setting of the tunnel sections does not lead to tearing off the legs and / or the webs provided on the legs. The distance is preferably chosen so that the leg ends are arranged on the expansion part sides.

In addition, the legs projecting downwards can be fed towards one another around the expansion part.

The joint tape 1 has on both sides of the expansion channel 2 on the inside three webs 3 arranged at the same distance from one another. The webs 3 are 4 to 5 cm long and ribbed.

According to Figure 1, the joint tape 1 is also provided with a vertical leg 4. The leg 4 has a length of at least 10 cm to the joint tape 1 and also has webs 5 on one side.

FIG. 2 shows, in a tunnel situation (not shown), the shotcrete layer 10 lying at the rock eruption, a plastic seal 11 with an outside fleece 12 lying on the inside of the shotcrete layer. The plastic seal 11 consists of a bitumen mixture containing ethylene copolymer. The plastic seal 11 is composed of individual webs welded together. The weld seams are not shown.

The concrete for the tunnel sections is poured onto the plastic seal 11. FIG. 2 shows a ridge area with two abutting tunnel sections 15 and 16. There is a joint 17 at the joint. In relation to the tunnel sections 15 and 16, the plastic seal 11 is on the outside.

At the joint 17, the joint tape 1 is welded to the plastic seal 11. The associated weld seams 20 are located at each free end of the joint tape leg that can be seen in cross section.

The above arrangement was achieved as follows: first the shotcrete 10 was applied to the rock eruption, then the plastic seal 11 with the fleece 12. The plastic seal 11 was secured against falling during its installation by means of holders in the shotcrete. The brackets consist, for example, of inlaid or hammered nails or the like, which are provided with a plastic cover for sealing. The plastic cover is then welded to the plastic seal. This creates a point-like fastening of the plastic seal 11, preferably in the ridge area. The attachment optionally has a predetermined breaking point, so that at certain tensile forces which occur in the seal 11, tearing off the cover or detaching the sealing membrane from the cover is ensured without at the same time causing damage to the seal.

The joint tape 1 has been welded to the plastic seal 11 in the joint area before the tunnel sections 15 and 16 are cast. Subsequently, the tunnel section 15 was first created, the vertical leg 4 of the joint tape 1 being attached to the ridge formwork for the tunnel section 15 in its lower region (nail tab) 18.

In the exemplary embodiment, the vertical leg 4 extends in the ridge area over an angle of approximately 90 on either side of the vertical through the middle of the tunnel. The vertical leg seals the joint 17 from water which, in the event of an unforeseen violation of the plastic seal 11 in the ridge area, flows through cavities formed there to the joint 17.

FIG. 3 shows a joint tape profile 101 according to the invention with a tubular expansion part 102, side legs 103 and 104 and legs 105 and 106 which point downward at 60 degrees. The legs 105 and 106 abut one another on the tubular expansion part 102, and they likewise close an angle between them of 60 degrees. The legs 103 and 104 together with the tubular expansion part form a joint tape surface which is smooth towards the top. This area is the contact area with the external seal in the tunnel. The welding takes place there.

The legs 103 and 104 are provided with webs 107 at the bottom (towards the tunnel interior). The legs 105 and 106 projecting downward have webs 108 toward the legs 103 and 104, respectively.

The tubular expansion part has a tubular cross section 109 in the drawn state of manufacture.

The dimensions of the exemplary embodiment according to FIG. 3 are 30 cm joint width, 4 cm web height for the webs 107 and 108, at least 10 cm leg length for the legs 105 and 106, 4 cm diameter for the open hose cross section 109. Otherwise, a material thickness of 8 mm intended for legs and bars.

The tubular expansion part 102 is formed in the side area at 110 and 111 such that the tangent in each point of the side areas 110 and 111 meets the associated legs 103 and 104 at an angle of less than 80 degrees. This creates an advantageous flow slope in the side areas 110 and 111.

The joint tape according to Figure 3 has been extruded. This requires relatively extensive extrusion tools and the position of the legs 105 and 106 shown in FIG. 3, the angle enclosed between the legs 105 and 106 being able to vary.

In the installation position shown in Figure 4, the legs 105 and 106 lie against each other. This can also be achieved with the help of a joint tape that has been welded together from conventional joint tapes.

For example, the welding can be carried out in such a way that two conventional joint tapes are angled without an expansion part until the two ends of legs 104 and 106 form one joint tape and legs 103 and 105 form the two ends of the other joint tape. After that, the two joint tapes are welded at the point of contact of the two legs 105 and 106. The connection between the legs 103 and 104 is realized by inserting and welding a strip of material of smaller thickness. It is not necessary for the tubular expansion part to have the identical cross section according to FIG. 3.

FIG. 5 shows a detail of an expansion part 120 of a joint tape according to the invention which is produced by welding several joint tapes. The expansion part 120 here has a triangular or trapezoidal shape, the material parts designated by 121 and 122 of two conventional joint tapes being provided by an internal extrusion seam 123 and optionally by one outer extrusion seam 150 shown in dash-dot lines are connected to one another. The top of the joint tape is closed by a web 124 which is welded to the two conventional joint tapes forming the joint tape according to the invention with weld seams 125 and 126.

When producing a joint tape according to the invention from conventional joint tapes to be welded to one another, the legs 105 and 106 can be brought into the installation position shown in FIG. 4 from the outset. In this position, the legs 105 and 106 are perpendicular to the legs 103 and 104.

In FIG. 4, the shotcrete at the rock eruption is 130, the external plastic seal is 131, and the concrete tunnel sections abutting here are designated 132 and 133. FIG. 4 shows that the webs 108 of the leg 105 are concreted into the tunnel section 133 and the webs 108 of the leg 106 are concreted into the tunnel section 132. This was done by first striking a leg 105 or 106 against the formwork of the tunnel section created first. The striking takes place e.g. B. by nailing in the area 136 or 137 (= nail tab).

In the exemplary embodiment, the downwardly projecting leg which is intended to be attached has been pushed upward by hand by approximately 3 cm below the deformation of the tubular expansion part 102 shown. If the tubular expansion part at 112 then breaks under appropriate tensile load, material of the tubular expansion part is available to a particular extent, which flows in the direction of the acting tensile force. The tubular expansion part 102 can also stand out from the concrete sections 132 and 133 at 134 and 135, respectively. This process is facilitated by a appropriate surface treatment of the plastic, e.g. B. greasing in the area of the tubular expansion part 102. However, this can also be effected by a plastic film which is concrete-repellent and is laminated onto the tubular expansion part. An embodiment according to FIG. 6 is particularly suitable for lamination. The lamination is then carried out on the conventional joint tapes which form the starting material in the region which forms the expansion part 120 after the welding of these joint tapes.

FIG. 5 shows a schematic illustration of a joint tape 140 with a leg 141 projecting downwards, which has two webs 142 and 143. FIG. 3 shows the joint tape 140 in an installation situation without shotcrete and the associated tunnel sections. In contrast to other joint tapes, the joint tape is provided at the ends of the legs 141 with further webs 144 and 145 which run parallel to the ends of the leg 141. The webs 144 and 145 seal off the space between the webs 142 and 143 or the web 143 and the joint tape part running in the circumferential direction, so that inflowing water cannot flow into the joint in the circumferential direction of the leg 141.

FIG. 5 shows a joint tape with a leg 141 limited to the ridge area. In particular when using a joint tape according to FIG. 6, it can be advantageous to provide circumferential legs. Ie legs are provided over the entire circumference of the tunnel, which protrude inwards.

FIG. 7 shows a schematic cross-sectional representation of a joint tape in a ridge installation position with horizontally extending legs 201 and 202. Each leg 201, 202 has webs 203 and 204 on the underside with which it is concreted into the associated tunnel sections.

A U-shaped expansion part 205 is located in the middle between the legs 201 and 202. This prevents concrete from penetrating the open cross-section of the U-profile.

The sides or vertical legs of the U-profile continue in legs 207 and 208 which project downwards and have webs 209 on the sides facing away from one another.

The leg 207 is concreted with its webs in the same tunnel section in which the webs 204 of the leg 201 are concreted. The leg 208 is concreted in with its webs 209 in the opposite tunnel section, in which the webs 203 of the leg 202 are also concreted in.

In the illustrated embodiment, it is ensured that there is sufficient material between the legs 207 and 208 to give the expansion part the possibility of sufficient deformation without the risk of cracking if the two associated tunnel sections are set differently. In this case, however, the film 206 that has performed its function after the joint tape has been installed can tear off.

FIG. 8 shows a schematic representation of a further joint tape, which is identical to the joint tape according to FIG. 1 except for another leg 210 projecting downwards. the leg 210 is longer than the leg 208 of the joint tape according to FIG. 1.

This serves to bend the leg 210 around the expansion part and to place the leg 210 close to the leg 207. This enables, while maintaining the o.b. Possibility of deformation during setting movement to arrange both downward projecting legs directly in the joint.

Claims (16)

1.Joint tape for structural joints in tunnel construction, which is welded to the outer seal in the joint area of two adjacent tunnel sections to be made in concrete, in particular with inwardly projecting webs and a tubular expansion part, characterized by at least one leg provided in the ridge area and projecting downwards ( 4). 2. Joint tape according to claim 1, characterized in that the leg (4) is arranged in the joint (17). 3. Joint tape according to claim 1 or 2, characterized in that the leg (4) is provided on one side with webs (5). 4. Joint tape according to one or more of claims 1 to 3, characterized in that two legs (105, 106) protrude downwards, the contact surface of the legs smooth and the sides of the legs (105, 106) facing away from one another with webs (108 ) are provided for concreting and / or at least webs (145) are provided on the leg ends present in the circumferential direction, which are arranged transversely or obliquely to the legs extending in the circumferential direction. 5. Joint tape according to claim 4, characterized in that the legs (105, 106) in the manufacture of the joint tape have an angle to the adjacent sealing tape part that is less than 90 degrees. 6. Joint tape according to claim 4 or 5, characterized in that the legs (105, 106) on a tubular expansion part (102) of the joint tape are arranged below and at the upper edge of the joint tape is a predetermined breaking point (112). 7. Joint tape according to claim 6, characterized in that the predetermined crack is formed in that the expansion part (102) has a lower band thickness at the predetermined tear than in the rest of the area. 8. Joint tape according to one or more of claims 4 to 7, characterized in that the outer walls of the expansion part (102) have a flow slope in the installed position. 9. Joint tape according to one or more of claims 4 to 8, characterized in that the legs (105, 106) are tacked and / or glued in the installed position at the lower or inner ends. 10. Joint tape according to claim 8, characterized by an adhesive with bitumen filler. 11. Joint tape according to one or more of claims 4 to 10, characterized in that the joint tape is composed of at least two conventional joint tapes without an expansion part. 12. Joint tape according to claim 11, characterized in that the two joint tapes in the region of the expansion part to be formed (120) with an inner of the legs (105, 106) connecting extrusion seam and outwardly with a welded material web (134) are provided. 13. Joint tape according to one or more of claims 4 to 12, characterized in that the tubular expansion part (102) on the lower side or the inner side with respect to the tunnel is pressed outwards. 14. Joint tape according to one or more of claims 4 to 13, characterized in that the leg ends connected to the expansion part (205) are spaced apart. 15. Joint tape according to claim 14, characterized in that the leg ends abut the expansion part sides. 16. Joint tape according to claim 14 or 15, characterized in that the legs (210) are guided around the expansion part (205).

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