EP0892872B1

EP0892872B1 - Sealing section for tunnel segments and tunnel comprising such sealing sections

Info

Publication number: EP0892872B1
Application number: EP98902287A
Authority: EP
Inventors: Hendrikus Kramer
Original assignee: Trelleborg Bakker BV
Current assignee: Trelleborg Bakker BV
Priority date: 1997-01-30
Filing date: 1998-01-30
Publication date: 2002-12-04
Anticipated expiration: 2018-01-30
Also published as: CN1166840C; NL1005140C2; DE69809846D1; CN1222947A; AU5884798A; WO1998033988A1; EP0892872A1; HK1021394A1

Description

The invention relates to a sealing section according to the preamble of claim 1. Such sealing section is known from US 3,680,270.

This known sealing section comprises a body provided with fastening means for fastening the section to a longitudinal edge of a first tunnel segment and a nose part extending from the body, which nose part can be brought into contact with an opposite longitudinal edge of a second tunnel segment. The body of this known sealing section is manufactured from a first material, the nose part from a second material. The nose part is more easily compressible than the body. In this known sealing section the nose part is made of solid material.

Furthermore, WO 96/27073 discloses a sealing section comprising a body and a nose part which nose part is positioned in a longitudinal groove provided in a top face of said body. The nose part extends partly outside the body and is made of a material, more easily compressible than the body. In this known sealing section the nose part is also made of solid material.

EP 0 375 427 discloses a sealing section extruded from one material, having a flat top surface, which, during use, connects to the flat top surface of a connecting sealing element. Under said top surface a series of channels is provided, connected to the high pressure side of the environment by openings. On this side of said channels chasing away from the top surface a number of legs is provided enclosing open channels, with which said sealing section is positioned in a groove of a tunnel segment.

From practice, furthermore, a sealing section is known which comprises a body provided, on a first side thereof, with two fastening flanges extending on opposite sides, while on the opposite, second side it is provided with a nose part. The section is manufactured in one piece from rubber. Against the facing longitudinal edges of two adjacent tunnel segments, a steel I-section is in each case mounted, which I-section is cast in the concrete of the relevant tunnel segment by means of anchors and partition plates. The short legs of the section lie parallel to the outside and inside of the tunnel walls, the intermediate flange being at right angles to the longitudinal direction of the tunnel segment. After the tunnel segment has settled, a steel fitted plate is welded on the open side of the I-section, between the short legs, which fitted plate is set with a minimal tolerance. Of course, this should be effected extremely accurately so that in each case the same distance is accurately obtained between adjacent fitted plates. After that, the section is provided on one of the fitted plates, with the foot formed by the two flanges and the intermediate side of the section.

During the positioning of concrete tunnel segments, which are substantially pipe-shaped, watertight partitions are placed near the free ends thereof, such that each tunnel segment comprises an air compartment. This enables the tunnel segments to float. After a first tunnel segment has been brought into position, a second segment is placed next to it, such that the tunnel section has its nose part abutting against the front plate of the adjacent tunnel segment. Thus, a water-filled chamber is formed between the watertight partitions of the segment already positioned and the segment to be positioned. In order to close the chamber in a watertight manner, the loose tunnel segment is pulled against the segment already positioned by means of a relatively light installation. This involves the nose part of the tunnel section being flattened against the front plate.
Subsequently, at least one hatch or the like in a watertight partition is opened, such that the pressurized water flows from the chamber at once, thereby creating a reduced pressure, while the water pressure against the end partition in the free tunnel segment presses this tunnel segment against the segment already positioned. Accordingly, the tunnel section is substantially completely flattened between the adjacent longitudinal edges of the tunnel segments.

The known sealing section has the drawback that the nose part is relatively low compared with the height of the section, and that the nose part permits a relatively slight deformation prior to deformation of the body part. This implies that in particular in the case of tunnel segments having relatively large dimensions, especially the flatness of the free longitudinal edges of the segments must be particularly accurate so as to be able to obtain sufficient sealing of the chamber. For this reason, among others, the fitted sections must be provided on the free longitudinal edges, which is a time-consuming and particularly costly affair. Moreover, this entails the danger of water possibly flowing along the back of the fitted section.

The object of the invention is to provide a sealing section of the type described in the preamble, in which the drawbacks mentioned are avoided, while the advantages thereof are maintained. To that end, a sealing section according to the invention is characterized by the features of claim 1.

The advantage of constructing the sealing section from two materials, with the nose part being more easily deformable than the body part, is that in the first phase of joining the tunnel segments, i.e. during the formation of the water-filled chamber, only the nose part deforms, which can take place in a relatively simple manner. Moreover, the advantage achieved by a suitable choice of the material for the nose part is that the nose part can be relatively high in comparison with the body, as a result of which great variations in the distance between the longitudinal edges of two tunnel segments to be placed next to each other can be bridged sealingly. Consequently, the fitted sections can be omitted while a sufficiently watertight and airtight chamber is nevertheless formed between the watertight partitions. In other words, the longitudinal edges can be manufactured with usual, relatively great tolerances from, for instance, concrete, and unevennesses of the longitudinal edges can readily be accommodated by the nose part while both sides of the sealing section can directly abut against the concrete longitudinal edges.

Through the openings in the sealing section, water can flow into the chamber of the nose part at a relatively high pressure, causing an excess pressure to be built up in the section, which presses the nose part tightly against the adjacent longitudinal edge, thereby providing an even better sealing. Upon further deformation of the sealing section, the water may possibly be forced at least partially from the chamber in the nose part.

In a particularly advantageous embodiment, a sealing section is further characterized by the features of claim 4.

Manufacturing the nose part separately from the body offers the advantage that the two parts are manufactured in a simple manner from different materials in different molds, for instance by extrusion or molding, and subsequently assembled to form the desired sealing section. This moreover offers a relatively great freedom of design in respect of the component parts, while channels can for instance readily be incorporated. Accordingly, an optimal deformation characteristic can in each case be obtained.

In a preferred embodiment, a sealing section according to the invention is characterized by the features of claim 7.

The nose part with the legs inclined relative to each other offers the advantage that this nose part can be flattened against the body almost completely, with the first, relatively large part of the deformation requiring relatively little force, i.e. the deformation force increases relatively slightly, while the deformation force during the final part of the deformation is relatively great, i.e. increases rapidly. The legs will bend outwards, as a result of which the frontal part of the nose part is pressed between the legs into the chamber and can hence be pressed away relatively easily.

In a further elaboration, a sealing section according to the invention is further characterized by the features of claim 11.

The flattened nose provides a relatively large contact surface between the nose part and the adjacent longitudinal edge, while moreover, a deformation of the nose part is suitably effected, such that the nose part is compressed transversely to the longitudinal direction, at right angles to the nose plane.

The invention further relates to a tunnel comprising a series of tunnel segments, which tunnel is characterized by the features of claim 13.

Further elaborations of a sealing section according to the invention are given in at least the subclaims.

To explain the invention, exemplary embodiments of a sealing section will be described hereinafter, with reference to the accompanying drawings. In these drawings:

Fig. 1 shows a cross section of an undeformed sealing section, mounted on a longitudinal edge of a tunnel section;

Fig. 2 shows a cross section of a sealing section according to Fig. 1, partially compressed between two tunnel segments;

Fig. 2A is a sectional top plan view of two tunnel segments, during the coupling thereof;

Fig. 3 shows a cross section of a sealing section in an alternative embodiment;

Fig. 4 shows the deformation characteristics of a known sealing section and of a sealing section according to the invention;

Fig. 4A shows the deformation characteristic of a nose part of a sealing section according to the invention; and

Fig. 5 is a top plan view of a tunnel segment having thereon a sealing section ready for transport and assembly.

Fig. 1 shows a sealing section 1, in cross section, having a body 2, two flanges 4 extending adjacent the base 3 of the section 1 on both sides of the body 2, and a nose part 5 extending on the side of the body 2 remote from the base 3. The body 2 is preferably manufactured from relatively rigid rubber, at least rubber which is relatively hard to deform, for instance having a hardness of 65 Shore-A or more, and the nose part 5 is preferably manufactured from less rigid rubber, at least rubber which can be deformed more easily, for instance having a hardness of 45 Shore-A. The nose part 5 is elongated and preferably manufactured through molding, although extrusion is possible as well.

The body 2 has its bottom side provided with two grooves 6, open towards the base 3 and extending in the longitudinal direction of the section 1, parallel to each other. Extending between the grooves 6 is a ridge 10 whose free side lies parallel to the otherwise flat base 3. By means of clamps 7 over the flanges 4, the section 1 can be secured against a longitudinal edge 8 of a tubular tunnel segment 9 manufactured from, for instance, concrete, with the nose part 5 extending in the direction away from the base, in the direction of a longitudinal edge 8' of a second tunnel segment 9'. In the center of the body 2, there is provided a channel 11 having an approximately circular cross section. The surface area of the cross section of the channel 11 is for instance approximately equal to that of the joint grooves 6.

The body 2 has an approximately rectangular or trapezoidal cross section, with two channel-shaped grooves 13 provided in the top face 12 thereof remote from the base 3, which grooves have a bottom 21 extending approximately parallel to the base 3 and, on the outwardly facing side, a wall 14 extending approximately at right angles to the top face 12. In the embodiment shown, the facing longitudinal walls 15 are inwardly inclined.

The nose part 5 has two inclined legs 16, which each have a relatively wide foot 17 and are interconnected at the side thereof remote from the body 2 by an end plate 18. The end plate 18 has an end face 19 on which a number of ridges 20 extend in parallel, for instance one along each side of the end face 19. Each foot 17 of the nose part 5 is positioned in one of the grooves 13 and is preferably fixed to the bottom thereof by gluing. Other manners of attachment are possible as well, such as vulcanizing, while if required, the nose part may be loosely arranged in the grooves. The foot 17 has a width which is slightly less than the width of the groove 13 and, on the inside thereof, a slightly greater height than the depth of the groove 13. The legs are relatively thin and positioned relative to each other and the end plate 18 such that the end plate 18 can move between the legs 16. Accordingly, between the legs 16, the end plate 18 and the body 2 a closed, airtight and watertight nose chamber 29 is enclosed. During a beginning, relatively slight loading of the nose part in a direction at right angles to the end face 19, the legs 16 bend away outwards, with the end plate being moved approximately vertically in the direction of the end face of the body 2 (Fig. 2). This involves the ridges 20 increasing the stability of the nose part 5 during deformation. As a result, for substantially the entire deformation of the nose part 5, only a relatively slight force is required, as appears from Fig. 4, left-hand side. Only when the nose part 5 is pressed completely flat against the body 2, is the body 2 deformed, for which a relatively high pressure is required, as likewise appears from Fig. 4, right-hand side. This will be further explained hereinbelow.

By means of a sealing section 1 according to Fig. 1, a tunnel is composed from at least two segments as follows.

In the above-described manner, the sealing section 1 is attached to the longitudinal edge 8 of a tunnel segment 9. Adjacent its two ends, the tunnel segment 8 comprises a watertight partition 22, whereinbetween an air compartment 23 is enclosed. This allows the tunnel segment 8 to float. A first tunnel segment 8' has already been placed on a bed. Next, the second tunnel segment 8, provided with the sealing section 1, is placed next to the free longitudinal edge 9' of the first tunnel segment 8, such that the nose part 5 has its ridges 20 lying against the free longitudinal edge 9' of the first tunnel segment 8'. As a result, a watertight chamber 24 filled with water is formed between the partition 22 of the second tunnel segment 8 and the partition 22' of the first tunnel segment 8'. Next, by means of a relatively light hauling apparatus, for instance a winch, the second tunnel segment 8 is pulled in the direction of the first tunnel segment, with complete deformation of the nose part 5 (Fig. 2A). The ridges 20 provide a relatively high closing pressure. During the deformation of the nose part 5, the water pressure in the chamber 24 is increased.

After the nose part has been deformed almost completely, a hatch 28 in the end partition 22' in the first tunnel segment 8' is opened, causing the water to flow from the chamber 24 and the pressure therein to fall out. Consequently, the second tunnel segment 8 is forced further in the direction of the first tunnel segment 8' by the water pressure on the end partition 22 remote from the first tunnel segment 8', with substantially complete compression of the body 2. Moreover, in this position, an additionally sealing section 31 can be provided on the side of the sealing section 1 facing away from the water, between the tunnel segments 8, 8'.

Fig. 4A shows, in a full line, the pressure force (F; left-hand vertical axis) on the nose part set out against the deformation (mm). In the same Figure, the contact pressure (N/mm²; right-hand vertical axis) is set out against the deformation (mm) in a broken line. As Fig. 4A clearly demonstrates, the force and the contact pressure between the nose part 5 and the longitudinal edge 8 increase at first (0-10 mm compression), after which they subsequently preferably remain constant or slowly decrease to near maximal deformation of the nose part. During the final part of the deformation of the nose part (35-40 mm), the pressure force increases relatively rapidly, while the contact pressure decreases slightly.

As appears from Fig. 4, in the known sealing section, both the force (kN/m) and the contact pressure in each case increase during deformation of the nose part, up to the maximal deformation of the nose part (appr. 25 mm). In comparison, for a compression of 20 mm in the known section (the complete nose part), a pressure of about 50 kN/m is required, which results in a contact pressure of about 0.6 N/mm². In the section according to the invention, a complete deformation of the nose part requires a compression of 40 mm, for which a force of only about 7.2 kN/m is needed, while a contact force of about 0.9 N/mm² is thereby obtained (fig. 4A).

Upon further deformation of the sections, maximal deformation of the known section (120 mm) results in a contact pressure of about 9 N/mm² at a closing force of 1800 kN/m, while maximal deformation of a section according to the invention (160 mm) results in a contact pressure of about 25 N/mm² at a closing force of 10000 kN/m. In comparison, during a deformation of 115 mm, the sealing section according to the invention given as an example results in a contact pressure of about 4 N/mm² at a closing force of about 1800 kN/m. This means that with a sealing section according to the invention, greater unevennesses in the longitudinal edges 9, 9' of the tunnel segments 8, 8' can be taken up at a lower loading for the pulling apparatus (lower initial pulling force), while relative movements for correcting the position of the section remain possible for a longer time, while eventually, a much greater contact pressure can be obtained.

The grooves 6 and in particular the ridge 10 between them provide a relatively high surface pressure of the ridge 10 on the longitudinal edge 9 of the tunnel segment 8. This prevents in a highly suitable manner water from possibly flowing along the back of the section 1, the so-called outflanking.

Fig. 3 shows an alternative embodiment of a sealing section according to the invention. The sealing section is substantially identical to the sealing section according to Figs. 1 and 2, yet in one of the legs 16 a series of openings 30 are provided. Each opening 30 connects the nose chamber 29 to the environment. The pressure in the chamber 24 is relatively low compared with the ambient pressure, which depends on the depth at which the tunnel segments are under water (meters of water pressure). In the tunnel segments, (approximately) atmospheric pressure will prevail. Due to the openings 30, the pressure in the nose chamber 29 is increased to approximately the ambient pressure, as a result of which the end plate 18 with the ridges 20 is pressed against the longitudinal edge 9 even more firmly, thereby providing an even better sealing. Moreover, during compression of the nose part 5, the water cannot flow away rapidly through the openings, so that this, too, will cause the pressure in the nose chamber to be relatively high.

Fig. 5 is a top plan view of a tunnel segment 8 ready for transport, having a sealing section 1 positioned thereon for transport. The sealing section is substantially O-shaped, i.e. round and closed in itself. It is for instance composed of four bends 1A and a number of straight pieces 1B connecting the bends, which straight pieces are fixedly connected relative to each other. A sealing section according to the invention can for instance have the following dimensions, which, as a matter of fact, should not be construed as being limitative in any way.

The body 2 is for instance manufactured from rubber having a hardness of 65 Shore-A, has a width of maximally 200 mm and minimally 180 mm, at a height of 190 mm. The nose part 5 is manufactured from rubber having a hardness of 45 Shore-A, has a maximal width of 120 mm (measured over the feet 17) and a minimal width of 40 mm (measured over the end plate 18), at a height of 70 mm outside the body 2. The legs 16 have a minimal thickness of 10 mm, the end plate has a thickness of about 25 mm, the ridges projecting about 4 mm from the end face 19. The total length of the sealing section is about 90 m. Deformation of the nose part 5 enables compensation of unevennesses in the longitudinal edges up to 40 mm, while this deformation can be realized by an initial pulling force of about 500/90 kN per meter sealing section or less (below 50 ton). During use, the sealing section can readily take up deformations caused by, for instance, creep, tolerances, movements of the tunnel segments, and temperature fluctuations. The dimensions and materials for the sealing section may of course be chosen differently, depending on the intended practical circumstances.

The invention is by no means limited to the embodiments described in the specification and shown in the Figures. Many variations thereto are possible.

For instance, a number of nose parts may be provided side by side on a body, while, if necessary, the facing legs of the nose sections may be provided with openings through which, during compression, water can flow from the intermediate space into the nose chambers of the nose sections for further increasing the pressure therein. Further, a sealing section according to the invention may be provided with a closed nose part or a nose part having a different cross section, for instance a semicircular or otherwise curved cross section, while, moreover, the body may be formed differently, for instance without channel or, conversely, with a number of channels, depending on the desired deformation characteristic. Further, types of fasteners other than flanges may be provided for the sealing section. The or each nose part may be loosely positioned in the grooves in the body but may also be secured therein, for instance by gluing or welding or by other fastening means. Both the body and the nose part may be manufactured from materials other than rubber, for instance from suitable synthetic material. A tunnel according to the invention is preferably manufactured from concrete tunnel segments, yet other materials are also possible, while the tunnel segments may have any desired shape and dimensions.

These and many other variations are understood to fall within the framework of the invention as defined in the claims.

Claims

A sealing section (1) for tunnel segments, comprising a body (2) provided with fastening means (4) for fastening the section to a longitudinal edge (8) of a first tunnel segment (9) and a nose part (5) extending from the body (2), outside the contour of the cross-section of said body (2)which nose part (5) can be brought into contact with an opposite longitudinal edge (8) of a second tunnel segment (9), wherein the body (2) is manufactured from a first material and the nose part (5) is manufactured from a second material, the nose part (5) being more easily compressible than the body (2), characterized in that the nose part (5) is provided with a chamber (29) substantially lying outside said contour of the body (2), further provided with a number of openings (30) connecting the chamber (29) to the environment on the side which, during use, faces the relatively high water pressure.
A sealing section (1) according to claim 1, characterized in that when the nose part (5)is compressed, the openings (30) are substantially pressed shut.
A sealing section (1) according to claim 1 or 2, characterized in that the first material has a higher hardness than the second material.
A sealing section (1) according to claim 3, characterized in that the first material is rubber having a hardness of more than 60 Shore and the second material is rubber having a hardness of less than 60 Shore, in particular maximally 50 Shore, preferably about 45 Shore.
A sealing section (1) according to any one of the preceding claims, characterized in that the nose part (5) is mounted on the body (2).
A sealing section (1) according to claim 5, characterized in that the body (2) has a substantially approximately rectangular or trapezoidal cross section, the fastening means (4) being provided near a base (3) of the body (2) and the body (2) being provided, on the side thereof remote from the base (3), with at least one groove (13) in which a foot (17) of the nose part (5) is placed, the nose part (5) projecting out of the groove (13).
A sealing section (1) according to claim 5 or 6, characterized in that the nose part (5) has a substantially triangular or trapezoidal cross section, the relatively wide base (3) being attached to the body (2).
A sealing section (1) according to claim 7, characterized in that the nose part (5), viewed in cross section, comprises two legs (16) which, viewed in the direction away from the body (2), are inclined in each other's direction, said legs (16) being connected on the side remote from the body (2) by an abutment part (18), while at least when the nose part (5) is undeformed, a cavity (20) is enclosed between the legs (16), the abutment part (18) and the body (2).
A sealing section (1) according to any one of the preceding claims, characterized in that during use, when the nose part (5) is loaded in a direction approximately at right angles to the longitudinal direction of the sealing section (1), in the direction of the body (2), the nose part (5) is substantially entirely compressed prior to deformation of the body (2).
A sealing section (1) according to anyone of claims 1-9, wherein the nose part is open on the side facing the body (2), such that the chamber (29) is closed by the body (2).
A sealing section (1) according to any one of the preceding claims, characterized in that the tip (19) of the nose part is flattened to form an end face, while at least one, preferably two or more ridges (20) extending parallel to each other are provided on the end face (19).
A sealing section (1) according to any one of the preceding claims, characterized in that the body (2) has its base (3) provided with at least two parallel grooves (6).
A tunnel comprising a series of tunnel segments (9) which extend under water and are interconnected at corresponding longitudinal edges (8), while between the longitudinal edges (8) a sealing section (1) according to any one of claims 1-12 is included.