Removable and replaceable anchored tunnel gasket

Abstract

A gasket for concrete structures such as tunnel segments includes a gasket body having a bottom face configured to be positioned against a surface of an associated tunnel segment. First and second anchor members protrude from opposed side edges of the gasket adjacent the bottom face of the gasket. The anchor members are configured to attach the gasket to the tunnel segment during casting of a precast concrete member. The gasket body forms a groove in the concrete member and the anchor members form side channels in the groove. Should a defect be found in the original gasket, the gasket body can be removed from the groove of the concrete member relatively easily, even in the field, and a replacement gasket having corresponding anchor members can be snapped into the groove.

Claims

1. A gasket construction for concrete structures, the gasket construction comprising: a gasket body comprising a resilient material and including in cross-section a base wall, a first side wall, a second side wall, and a top wall; a first anchor member extending from the gasket body adjacent the first side wall and the base wall; a second anchor member extending from the gasket body adjacent the second side wall and the base wall; wherein the first and second anchor members each comprise protrusions which in cross-section have at least one of planar and rounded faces; wherein the gasket body is capable of use with a concrete structure including a groove formed in the concrete structure for the gasket body and two spaced side channels for the first and second anchor members, which side channels are open to the groove; and wherein the first and second anchor members are configured to be held in the respective side channels, and wherein the first and second anchor members are constructed such that the gasket body is selectively detachable in an intact manner from the groove.

2. The gasket construction of claim 1 further comprising at least one bore extending longitudinally in the gasket body.

3. The gasket construction of claim 2 wherein a plurality of spaced bores extend longitudinally in the gasket body and wherein the plurality of bores extend in a common direction.

4. The gasket construction of claim 3 wherein a cross-sectional shape of the plurality of spaced bores is one of a triangular shape, a semi-circular shape, a bell shape and a U-shape.

5. The gasket construction of claim 3 wherein a durometer of the first and second anchor members is different than a durometer of the gasket body.

6. The gasket construction of claim 1 wherein the gasket body comprises ethylene propylene diene monomer (EPDM), Neoprene or a similar rubber material.

7. The gasket construction of claim 1 further comprising a first lip extending away from the first side wall of the gasket body and a second lip extending away from the second side wall, wherein the first and second lips are spaced away from the first and second anchor members.

8. The gasket construction of claim 1 further comprising a first protrusion extending away from the first side wall of the gasket body and a second protrusion extending away from the second side wall, and wherein the first and second protrusions are spaced from the first and second anchor members.

9. The gasket construction of claim 1 wherein the first and second anchor members are of the same size.

10. A construction including a cast-in-place gasket for a concrete structure, the construction comprising: a gasket body formed from a resilient material, the body including in cross-section a base wall, a first side wall, a second side wall and a top wall; a first anchor member protruding from the first side wall of the gasket body and located adjacent the base wall; a second anchor member protruding from the second side wall of the gasket body and located adjacent the base wall; wherein a face of the first and the second anchor members is at least one of planar and rounded; a concrete structure comprising a groove formed in the concrete structure by the gasket body when the concrete structure is cast and a pair of spaced side channels open to the groove, which side channels are formed in the concrete structure by the first and second anchor members when the concrete structure is cast; and wherein the first and second anchor members are held in a respective one of the side channels, and wherein the first and second anchor members are constructed such that they are selectively detachable in an intact manner from the side channels and the gasket body is constructed such that it is selectively detachable in an intact manner from the groove defined in the concrete structure.

11. The construction of claim 10 further comprising at least one bore which extends in the gasket body in a direction parallel to a longitudinal axis of the gasket body.

12. The construction of claim 10 wherein a durometer of the first and second anchor members is different from a durometer of the gasket body.

13. The construction of claim 10 further comprising a first protrusion extending away from the first side wall of the gasket body and a second protrusion extending away from the second side wall of the gasket body, and wherein the first and second protrusions are spaced from a respective one of the first and second anchor members.

14. The construction of claim 13 further comprising a first lip extending away from the first side wall of the gasket body and a second lip extending away from the second side wall of the gasket body, wherein the first and second lips are positioned, respectively, between the first and second anchor members and the first and second protrusions.

15. A construction including a cast-in-place gasket and a concrete structure in which the gasket is held, the construction comprising: a gasket body formed of a resilient material, the gasket body having a longitudinal axis and including in cross-section a base wall, a first planar or curved side wall, a second planar or curved side wall, and a top wall; a first anchor member protruding radially from the first side wall of the gasket body and located adjacent the base wall and running along the longitudinal axis of the gasket body; a second anchor member protruding radially from the second side wall of the gasket body and located adjacent the base wall and running along the longitudinal axis of the gasket body; wherein the first and second anchor members each include a face which is at least one of planar and rounded; a concrete structure including a groove formed in the concrete structure by the gasket body during the casting in place of the gasket and a pair of spaced side channels formed in the concrete structure by the first and second anchor members, which spaced side channels are open to the groove; and wherein the first and second anchor members are constructed such that the first and second anchor members are selectively detachable in an intact manner from the side channels and the gasket body is selectively detachable from the groove in the concrete structure in an intact manner.

16. The construction of claim 15 further comprising at least one bore which extends in the gasket body in a direction parallel to a longitudinal axis of the gasket body.

17. The construction of claim 15 wherein a durometer of the first and second anchor members is different from a durometer of the gasket body.

18. The construction of claim 15 further comprising a first protrusion extending away from the first side wall of the gasket body and a second protrusion extending away from the second side wall of the gasket body, and wherein the first and second protrusions are spaced from a respective one of the first and second anchor members.

19. The construction of claim 18 further comprising a first lip extending away from the first side wall of the gasket body and a second lip extending away from the second side wall of the gasket body, wherein the first and second lips are positioned, respectively, between the first and second anchor members and the first and second protrusions.

20. A method for replacing a defective gasket in a concrete structure comprising: providing a gasket body including first and second anchor members extending, respectively, from the gasket body on opposed side walls of the gasket body adjacent a base wall thereof; providing a concrete structure including a groove formed by the gasket body and a pair of opposed side channels formed by the first and second anchor members, which side channels are open to the groove; removing the gasket body from the groove and removing the first and second anchor members from the side channels, wherein the gasket body comprises a resilient material and the first and second anchor members are so constructed that the anchor members are detachable in an intact manner from the side channels open to the groove and the gasket body is constructed so that it is detachable from the groove in an intact manner; and providing a replacement gasket including a gasket body and first and second anchor members; and inserting the replacement gasket body into the groove and the anchor members into the side channels of the concrete structure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure may take physical form in certain gasket designs and arrangements, several embodiments of which will be described in detail in the specification and illustrated in the accompanying drawings which form a part hereof and wherein:

(2) FIG. 1 is cross-sectional view of a portion of a concrete segment provided with a first type of prior art gasket which is anchored into the concrete segment;

(3) FIG. 2 is a perspective view of a second type of prior art gasket which can be glued in place in a groove formed in a concrete segment;

(4) FIG. 3 is a perspective view of a third type of prior art gasket which is said to be fiber-anchored in a groove formed in a concrete segment;

(5) FIG. 4 is a cross-sectional view of a gasket according to one embodiment of the present disclosure, as installed in a concrete segment;

(6) FIG. 5 is a perspective view of the gasket of FIG. 4;

(7) FIG. 6A is a cross-sectional view of a gasket according to another embodiment of the present disclosure;

(8) FIG. 6B is a cross-sectional view of a gasket according to still another embodiment of the present disclosure;

(9) FIG. 6C is a cross-sectional view of a gasket according to yet another embodiment of the present disclosure; and

(10) FIG. 7 is a cross-sectional view of a gasket according to a further embodiment of the present disclosure.

DETAILED DESCRIPTION

(11) It should be understood that the description and drawings herein are merely illustrative and that various modifications and changes can be made to the gaskets disclosed herein without departing from the present disclosure. In the drawings, the showings illustrate several embodiments. Several gasket designs according to the prior art and according to the instant disclosure are discussed but the instant disclosure is not intended to be limited to the disclosed embodiments.

(12) With reference to FIG. 1, a gasket A according to a first known design of the prior art includes a gasket body 10 which is provided with one or more depending anchoring feet 12. These are embedded in a concrete segment 14 as the concrete is poured around the gasket. Such prior art gaskets, also known as cast-in-place gaskets, are directly anchored in the concrete segment via the anchoring feet 12 in order to keep the gasket in position in the concrete segment. As mentioned above, removal and replacement of the gasket A is difficult because the feet are embedded in the concrete. In fact, in the field, there is no quick or easy way to replace a defective gasket and make a concrete segment with such a defective gasket usable again.

(13) FIG. 2 illustrates a second known prior art design in which a gasket B includes a gasket body 20 which is provided with one or more legs 22 forming a bottom surface of the gasket. The legs and also opposing lower side faces of the gasket body 20 can be secured in place in a groove formed in a precast concrete segment by gluing the gasket to the concrete segment via a conventional adhesive 24. The adhesive is located between the bottom face of the gasket and the lower side faces thereof and the adjacent walls of the groove formed in the concrete segment. Field removal of a defective gasket B incurs significant labor costs. These include the removal of a defective gasket, the cleaning of the groove to remove any remaining gasket material or adhesive, the installation of a replacement gasket, and securing the replacement gasket in place with adhesive.

(14) FIG. 3 illustrates a third known prior art design in which a gasket C is mounted in a groove formed in a concrete segment. In this design, a lower face 32 of a gasket body 30 is provided with a fiber layer 34. However, fiber-anchored gaskets may not be anchored in the groove sufficiently firmly, particularly during the process of installing tunnel segments. Also, the necessity of providing the gasket bottom with thousands of fibers add significantly to the cost of this prior art gasket.

(15) With reference now to FIG. 4, a gasket D according to a first embodiment of the present disclosure includes a gasket body 40 which includes a base wall 42. First and second anchor members 44 and 46 protrude from the gasket body. These are located on opposed side walls 48 of the gasket body and are located adjacent the gasket base wall 42. In one embodiment, the anchor members 44 and 46 can be considered as protrusions which in cross-section can have at least two planar wall sections that are oriented at an acute angle in relation to each other. Of course, other shapes are also contemplated for the anchor members, as will be discussed below. The anchor members 44 and 46 serve to retain the gasket in the groove of the concrete segment mold during casting of the precast concrete member or segment.

(16) The gasket body 40 also includes opposed first and second lips 50 and 52 which can extend from the two opposed side walls 48. As is evident from FIG. 4, the lips serve to seal the groove in the concrete segment mold. Furthermore, the lips are considered advantageous in that they can serve to retard the seepage of liquids into the groove defined in the surface of the concrete segment. In this design, the gasket body also includes first and second protrusions 54 and 56 which are located on the opposed side walls 48 adjacent a top wall 58 of the gasket body. It should be apparent from a review of FIG. 4 that in this embodiment of the gasket, the first and second lips 50 and 52 are vertically spaced from the first and second anchor members 44 and 46. Similarly, the first and second protrusions 54 and 56 are vertically spaced from the lips 50 and 52. Thus, the lips 50 and 52 are disposed between the anchor members 44 and 46 on the one hand, and the first and second protrusions 54 and 56 on the other hand. It is also noted that the anchor members 44 and 46 are larger than are the first and second protrusions 54 and 56 in this embodiment of the gasket. Of course, other designs are also contemplated.

(17) It should be apparent that one or more bores 62 of varying shapes in cross-section, including, triangular, semi-circular, bell-shaped or U-shaped, among others, can extend longitudinally through the gasket body 40 as is known in the art.

(18) As mentioned, the gasket D is selectively secured to or mounted to a concrete segment 70, namely, the gasket is positioned in a groove 72 defined in the segment. The gasket D is held in place while the concrete member is cast around the gasket. Thus, the gasket defines or forms a groove in the concrete which flows around it. The first and second anchor members 44 and 46 extend into side channels 74 defined in the groove 72 of the concrete segment 70. It should be apparent from FIG. 4 that the anchor members 44 and 46 are held in the groove defined in the concrete segment. The anchor members provide a V-shape to the side channels 74 in this embodiment, in a complimentary fashion so that the anchor members simply sit in the side channels in use.

(19) Should the original gasket in the concrete member or segment require replacement, the original or old gasket can be removed by simply pulling the gasket out of the groove and a replacement or new gasket can be snapped into place. The gasket can be pulled out of the groove due to the inherent resiliency of the material from which the gasket is manufactured. The first and second anchor members 44 and 46 are sized such that the gasket body is selectively detachable from the groove 72 defined in the concrete segment 70. The side channels 74 are located adjacent the side edges of the groove 72 such that the apexes of the V-shaped channels 74 defined in this embodiment are located above a base surface of the groove 72. Due to the resilient nature of the material from which the gasket is made, the gasket body 40 is able to flex enough so that a damaged gasket is removable and replaceable when that becomes necessary. The first and second lips 50 and 52 are positioned at a surface 76 of the concrete segment as is evident from FIG. 4.

(20) With reference now also to FIG. 5, in the embodiment illustrated, the gasket D can extend a desired length, normally the length of the face of the concrete segment, and can include two opposed planar wall segments 80 and 82 which define each of the anchor members 44 and 46. As mentioned, the two planar or flat wall segments 80 and 82 can be disposed at an acute angle in relationship to each other. Thus, a generally V-shaped configuration in cross-section is provided for each of the anchor members 44 and 46. While the anchor members 44 and 46 are illustrated as containing two planar wall segments, it should be appreciated that anchor members having other geometric shapes, which may include three or more planar or otherwise-shaped wall segments is also contemplated.

(21) An interference fit is provided between the groove 72 of the concrete segment 70 and the gasket body 40 such that the anchor members 44 and 46 can snap into and be pulled out of the side channels 74. One advantage of the gasket D is that it can be removed from groove 72 without the need for extraordinary effort or equipment. The reason why the gasket D can be selectively removed from its groove 72 without extraordinary effort is that the anchor members are so sized, and the gasket is comprised of an elastomeric material which allows the gasket body to be selectively detachable from the groove 72. This construction allows a defective gasket to be replaced in the field if that becomes necessary.

(22) The gasket D may be made from a suitable elastomeric material such as, for example, ethylene propylene diene monomer (EPDM) rubber. Alternatively, one or more other elastomers having a Shore A hardness in the range of 30 to 75 can also be used. As such, many elastically deformable synthetic materials are useable for the material of the several gasket embodiments disclosed herein. Also, dual hardness gasket constructions are contemplated which can include a harder anchor section (i.e. the two anchor members being of a greater durometer) and a softer sealing section, i.e., the remainder of the gasket body being of a lesser durometer, or at least selected portions thereof can be of a lesser durometer. A co-extrusion of two different durometer elastomeric materials is thus contemplated in this embodiment. Alternatively, the body can be stiffer and the anchor sections softer under some circumstances.

(23) With this design, the gasket D functions as an anchored gasket for concrete segment manufacturing. Yet, the gasket can be removed if it becomes damaged and replaced with another gasket either at the casting plant, in the storage yard, or on the job site. No extraordinary efforts or equipment are required for field removal and replacement of the gasket D. In this way, labor costs are greatly decreased, positively affecting project budgets. Moreover, no additional material, such as adhesive or fibers (which can be costly), is necessary to mount the gasket D to a concrete segment and secure it in place.

(24) In one embodiment, the gasket can have a thickness of about 0.7 inches (1.8 cm) and a width of about 1.21 inches (3.07 cm) at the tips of the anchor members 44 and 46. The fins or lips 50 and 52 may protrude outwardly from the body 40 of the gasket such that the complete width of the gasket can be about 1.425 inches (3.62 cm). The width of the gasket at the first and second protrusions 54 and 56 can be about 1.152 inches (2.93 cm) if so desired. It should be appreciated that the lips 50 and 52 can be so located on the side surfaces of the gasket that the top surface of the lip is about 0.382 inches (0.97 cm) below the top surface of the gasket.

(25) The anchor tip area of the gasket D basically needs to provide an inset recess which allows the concrete to enclose or trap the gasket base. Dimensionally, the anchor tip dimension can range from 0.060 to 0.200 inches (0.15 to 0.51 cm) per side depending upon the size of the gasket profile. Gasket profiles can range from 0.095 to 1.750 inches wide (0.24 to 4.45 cm). Since the gasket body hinges during its removal or replacement, the extension dimension of the anchor tips into the concrete will be altered as necessary based on the profile's overall width.

(26) With reference now to the embodiment illustrated in FIG. 6A, a gasket E according to another embodiment of the instant disclosure includes a gasket body 90 having a base wall 92. Positioned on opposed side edges of the base wall 92 and extending from the side walls of the gasket E are first and second anchor members 94 and 96. In this embodiment, the anchor members have a generally semi-circular, curved or rounded configuration in cross-section as at 98. The anchor members 94 and 96 are designed to cooperate with suitably shaped side channels formed in a concrete segment (not illustrated). Also provided are first and second lips 100 and 102. As with the embodiment of FIG. 4, a defective or damaged gasket E can be removed from a groove in the concrete segment and replaced if that becomes necessary in the field without having to either scrap the concrete segment or send it back to the casting facility for repair or replacement of the gasket. The rounded face 98 of the first and second anchor feet 94 and 96 allows the gasket E to be readily snapped into the side channels formed in the concrete segment groove and be removed therefrom without undue effort.

(27) With reference now to FIG. 6B, a gasket F according to still another embodiment of the present disclosure includes a gasket body 110 which is provided with a base wall 112, as well as anchor members 114 and 116 located on opposed side edges of the base wall. In this embodiment, the anchor members each include a first planar section 120 and a second planar section 122. Unlike the V-shaped configuration illustrated in the embodiment of FIGS. 4 and 5, FIG. 6B shows an embodiment in which the two planar sections of the anchor members are not disposed at an acute angle in relationship to each other. Rather, they are disposed at an obtuse angle in relationship to each other. As with the previous embodiments, the gasket F can be removed from side channels defined in a groove in a concrete segment without undue effort and a new gasket can be installed if that becomes necessary, even in the field.

(28) With reference now to FIG. 6C, illustrated there is a gasket G according to yet another embodiment of the present disclosure. This embodiment includes a gasket body 130 having a base wall 132 and first and second anchor members 134 and 136 disposed on opposed side edges of the base wall of the gasket body. In this embodiment, the anchor members 134 and 136 each include a planar or flat upper section 140 and a rounded or curved lower section 142 disposed beneath the planar section. It should be appreciated that the side channels defined in the groove of the concrete segment are correspondingly shaped in the process of the concrete being cast around the gasket so as to readily accommodate the anchor members 134 and 136.

(29) With reference now to FIG. 7, illustrated there is a gasket H according to a further embodiment of the present disclosure. This embodiment includes a gasket body 150 having a base wall 152 and first and second anchor members 154 and 156 which are disposed on opposed side edges of the base wall and located at the side walls of the gasket body. In this gasket embodiment, the anchor members 154 and 156 can each have a rounded face as at 158. In this embodiment, the gasket body 150 can be made of a closed cell sponge-type elastomeric material 162. Unlike the embodiments illustrated in FIGS. 4, 5 and 6A-6C, the gasket body 150 does not have any longitudinally extending bores defined in the gasket body. In the absence of bores, the closed cell sponge-like material 162 of the gasket H needs to be compressible enough so that it can be relatively easily removed from a groove defined in a concrete segment if that becomes necessary with the respective anchor members of a replacement gasket snapping into the side channels in the groove.

(30) As previously noted, the material of the gasket body in the embodiments of FIGS. 4-6C can typically be made of EPDM (ethylene propylene diene monomer) or Neoprene (polychloroprene or pc-rubber) which is a synthetic rubber that can have a durometer of 65 to 75 on the Shore A hardness scale. Regarding the sponge-type gasket H illustrated in FIG. 7, the material can be a medium to firm density EPDM, Neoprene or a similar rubber or elastomeric material. It can be a 2A3/2A4 or 2C3/2C4 material on the ASTM D1056 standard for cellular materials. The density of the material would be determined based on the closure force required for the contemplated concrete tunnel segments. In this type of material, instead of a durometer measurement on the Shore A hardness scale, the force in PSI which is required to compress the material to 25% of its thickness is measured and stated in compression deflection units. One advantage of the material illustrated in FIG. 7 is that the sponge-type material of the gasket is designed to compress with less force than the generally denser material of the gaskets illustrated in FIGS. 4-6C. The sponge-type gasket H would be most frequently used in low pressure applications (<5 bar) where installation methods rely on the weight of the concrete segment to close the joints. Such joints are generally found in vertical installations, such as in shafts and the like.

(31) Disclosed has been a tunnel segment gasket which includes first and second anchor members that protrude from opposed side edges at the base of the gasket. The anchor members are configured to attach the gasket to a concrete tunnel segment during the casting of the pre-cast concrete tunnel segment. As the tunnel segment is being cast from concrete, the gasket forms a groove in the concrete, including forming side channels in the groove, the side channels being defined by the anchor members of the gasket. Should a defect be found in the gasket which has been cast-in-place in the concrete tunnel segment or like concrete member, such a defective gasket can be removed from the groove relatively easily. A replacement gasket can then be snapped into the groove in place of the original gasket. The replacement gasket will have corresponding anchor members which will extend into the side channels defined in the groove of the associated concrete member.

(32) If a cast-in-place gasket according to the present disclosure has become defective, either at the manufacturing plant or in the field, it can be removed and replaced with an intact gasket in an economical and time efficient manner. More particularly, because the gasket when it was cast-in place formed not only a groove in the concrete structure but also first and second side channels extending from the groove due to the presence of the anchor members, the gasket body can be removed in an intact manner from the groove such that the anchor members are pulled out of the side channels. This is possible because the gasket body comprises a resilient material and the first and second anchor members are so sized that the gasket body is detachable from the concrete structure in an intact manner thereby simplifying its removal. A replacement gasket body could also include first and second anchor members of the same size as the one which was removed. The replacement gasket body can be inserted into the groove such that the anchor members are inserted into the side channels of the concrete structure. In this way, a replacement gasket can be installed in the field eliminating the need for the use of glue or adhesive, as well as the potential need for returning the concrete member (such as a tunnel segment) from the field back to the factory for the installation of such a replacement gasket.

(33) The present disclosure has been described with reference to several embodiments. Obviously, modifications and alterations will occur to others upon a reading and understanding of the preceding detailed description. It is intended that the present disclosure be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.