GB2221972A

GB2221972A - Tubular members for forming conduits

Info

Publication number: GB2221972A
Application number: GB8917272A
Authority: GB
Inventors: John Wilfred Thomas Ropkins
Original assignee: AEB Jacked Structures Ltd
Current assignee: AEB Jacked Structures Ltd
Priority date: 1988-07-28
Filing date: 1989-07-28
Publication date: 1990-02-21
Also published as: GB2224553A; GB8818014D0; GB8917272D0; GB2224553B; GB8917271D0

Abstract

In a plurality of tubular members (1, 1') arranged end to end to form a conduit, at least one of the tubular members (1) is provided at one end with a sealing member (2) extending around the tubular member and projecting from its end surface (1a). At least one other adjacent tubular member (1') is provided at one end with a sealing recess (3') containing sealant (4), which extends around the tubular member (1') and is arranged to accommodate at least a portion of the sealing member (2). <IMAGE>

Description

"Improvements in and relating to tubular members for forming conduits" The invention relates to tubular members for forming conduits.

The invention provides a plurality of tubular members arranged end to end to form a conduit, at least one of the tubular members being provided at one end with a sealing member extending around the tubular member and projecting from the end surface of the tubular member in a direction substantially parallel to the axis of the tubular member and at least one other adjacent tubular member being provided at one end with a sealing recess extending around the tubular member, the sealing recess being arranged to accomodate at least a portion of the sealing member.

Advantageously, the sealing recess contains a plastic sealant material and a portion of the sealing member is embedded in the sealant material to form a seal. The sealant material is advantageously a non-hardening material and is, preferably, a material of such shear strength and capable of such adhesion to the material from which both the sealing member and the tubular members are made that relative movement of the sealing member and the sealing recess can take place without the sealant material de-bonding from the sealing member or theEsealing recess.

The sealant material is, preferably, capable of being inserted into the sealing recess without the application of heat. For example, the sealant material may be a petrolatum or rubber bitumen compound. With such an arrangement, it is possible for a certain amount of relative movement, especially longitudinal movement, to take place without destroying the seal formed by the sealing member in the sealing recess.

The sealing member is advantageously made from a non-corrosive material, for example, a metal such as stainless steel, copper or aluminium, or a plastics material.

In the case of tubular members made by casting concrete, the sealing member is advantageously secured in the tubular member when it is cast, and the sealing recess is also formed during the casting process.

The sealing member may be so arranged that it leaves the end surface of its tubular member (and the sealing recess so that it meets the end surface of its tubular member) at a position which is located approximately halfway between the outer surface of the tubular member and its inner surface (that is to say, a position which is located approximately 0.5 of the distance between the outer and inner surface). At least in a process which involves inserting the tubular members into the ground by applying a jacking load to the tubular members along their axis as, for example, in a so-called "pipe-jacking" process, however, it is advantageous for that position to be offset from the halfway position in order that there should be a sufficiently large, uninterrupted area for the application, and transmission, of the jacking load.

The sealing recess is advantageously of substantially greater dimensions than the sealing member to facilitate insertion of the sealing member in the sealing recess.

The arrangement of the invention may be used when the end surfaces of the tubular members are substantially planar and butt joints are formed between adjacent tubular members. The arrangement may also bused when the ends of adjacent tubular members are so shaped that spigot and socket joints are formed between them.

In addition, the arrangement of the invention may be used when the tubular members are as described and claimed in our co-pending United Kingdom Patent Application No

Accordingly, the arrangement may be such that at least one of the tubular members has at one end a plurality of projecting portions and at least one other adjacent tubular member has at one end a plurality of recesses, the projecting portions of the said one tubular member being arranged to mate with the recesses of the said adjacent tubular member to locate the tubular members relative to each other, and each of the projecting portions and each of the recesses having a pair of bearing surfaces, one bearing surface of each pair being arranged to resist movement by a mating tubular member relative to it in one direction around the periphery of its tubular member and the other bearing surface of each pair being arranged to resist movement of a mating tubular member relative to it in the opposite direction.

The projecting portions and their mating recesses may extend (in a direction normal to the axis of the tubular members) over substantially the entire thickness of the walls of their respective tubular members, or only over half or the greater part of the thickness. In the latter case, the sealing member and the sealing recess are advantageously located within the other, remaining part.

When the said projecting portions and mating recesses extend from the outer surface of the tubular member towards the inner surface across only half or the greater part of the thickness of the wall of the tubular members, the portion of the end surface extending over the other, remaining part of the thickness may be so arranged as to provide a spigot or a socket so that spigot and socket joints are formed between adjacent tubular members.

When the conduit comprises only two tubular members, the end surface of the wall of each tubular member at the opposite end to the sealing member and the sealing recess, respectively, may be planar, if desired. When three or more tubular members are used to form the conduit, it is advantageous for at least the or each intermediate tubular member to have at one end a sealing member for insertion into a sealing recess of an adjacent tubular member and at its opposite end a sealing recess for the sealing member of an adjacent tubular member.

Accordingly, the invention also provides a tubular member for forming a conduit with one or more other such tubular members arranged end to end, the tubular member being provided at one end with a sealing member extending around the tubular member and projecting from the end surface of the tubular member in a direction substantially parallel to the axis of the tubular member and being provided at its other end with a sealing recess extending around the tubular member, the sealing recess being arranged to accomodate at least a portion of the sealing member of another such adjacent tubular member.

The invention also provides a method of forming a conduit using a plurality of tubular members constructed in accordance with the invention, and a method of forming such a conduit wherein the tubular members, arranged end to end, are inserted into the ground. In such a method, a first tubular member may be urged into the ground, a second tubular member then arranged end to end with the first tubular member so that its sealing member or sealing recess mates with the sealing recess or sealing member, respectively, of the first tubular member, and the second tubular member urged into the ground, the first tubular member being urged further into the ground. One or more successive tubular members may then be inserted into the ground in a similar manner to the second tubular member until a conduit of the required length is formed in the ground. Alternatively, at least first and second tubular members may be arranged end to end before insertion of the first tubular member into the ground, and the said tubular members then inserted into the ground by applying a load to the rearmost tubular member.

The method of the invention may also be as described and claimed in United Kingdom Patent Specification No.

2 185 277.

Several forms of tubular member constructed in accordance with the invention and suitable for use as one of the tubular members of a plurality of tubular members, arranged end to end to form a conduit, and several forms of conduit comprising a plurality of such tubular members arranged end to end and constructed in accordance with the invention, will now be described with reference to the accompanying drawings, in which:: Fig. 1 is a diagrammatic perspective view of one form of tubular member constructed in accordance with the invention; Fig. 2 shows diagrammatically, and on a larger scale than Fig.l, a section through a portion of the walls of two adjacent tubular members of the form shown in Fig.l and arranged end to end; Fig.3 is a diagrammatic perspective view of a second form of tubular member constructed in accordance with the invention; Fig. 4 shows diagrammatically, and on the same scale as Fig. 2, a section through a portion of the walls of two adjacent tubular members of a third form in accordance with the invention; and Fig. 5 shows diagrammatically, and on the same scale as Fig. 4, a section through a portion of the walls of two adjacent tubular members of a fourth form in accordance with the invention.

Referring to the accompanying drawings, and initially to Figs. 1 and 2, a tubular member, indicated generally by the reference numeral 1, is of square cross-section and is made, for example, of pre-cast reinforced concrete. One end surface la of the tubular member 1 is provided with a sealing member 2 which extends around the tubular member and projects from the end surface in a direction substantially parallel to the axis of the tubular member. The sealing member 2 may be set in position in the tubular member 1 when it is cast, and is made from a non-corrosive material, for example, a metal such as stainless steel, copper, or aluminium, or a plastics material. The sealing member 2 is so arranged that it leaves the end surface la at a position which is approximately one third of the distance from the outer surface lc to inner surface ld of the tubular member 1.

As can be seen in Fig. 2, to form a conduit, the sealing member 2 of the tubular member 1 is inserted into a sealing recess 3' of an adjacent tubular member l'similar to the tubular member 1 and arranged end to end. The sealing recess 3' extends around end surface l'b of the tubular member 1' and is of substantially greater dimensions than the sealing member 2 to facilitate insertion. The sealing recess 3' is arranged to meet the end surface l'b at a position approximately one third of the distance from the outer surface of the tubular member 1' to its inner surface.

The sealing recess 3' contains a soft plastic sealant material 4, which is non-hardening, of low shear strength and capable of good adhesion to both the materials from which the tubular members 1, 1' and the sealing member 2 are formed. The sealant material 4 can be inserted into the sealing recess 3' without the application of heat, and may be, for example, a petrolatum or rubber bitumen compound.

Upon insertion of the sealing member 2 in the sealing recess 3', a portion of the sealing member becomes embedded in the sealant material 4 to form a seal. If relative longitudinal movement takes place between the tubular members 1 and 1', and thus between the sealing member 2 and the sealing recess 3', the sealant material 4 is such that it shears within itself rather thdn de-bond from the sealing member 2 or the wall of the sealing recess 3'.

End lb of the tubular member 1 of Fig. 1 is formed with a recess similar to the recess 3' of the tubular member 1'.

Fig. 3 shows a tubular member indicated generally by the reference numeral 5 with a sealing member 6 extending around its end surface Sa in a similar manner to that of Fig. 1. The tubular member 5 is, however, also provided with four projecting portions 7 on its end surface 5a, one on each side of the tubular member. Each projecting portion 7 extends over the entire thickness of the wall of the tubular member 5 and has a pair of bearing surfaces 7a and 7b, respectively. The tubular member 5 at its other end is formed with recesses 8 corresponding to the projecting portions 7 in addition to a sealing recess similar to the sealing recess 3' shown in Fig. 2.The tubular member 5 can be arranged end to end with one or more similar tubular members to form a conduit of the required length, the projecting portions 7 mating with recesses similar to the recesses 8 of an adjacent tubular member and also helping the insertion of the sealing member 6 in its sealing recess. The projecting portions 7 and recesses 8 can prevent lateral movement between adjacent tubular members.

As can be seen in Fig. 4, a similar arrangement of a sealing member 10 in a sealing recess 11 containing a soft plastic sealant material 12 can be used with tubular members 13 and 13' having projecting portions 14' and mating recesses 15, respectively, similar to those of the tubular member 5 of Fig. 3 but extending over only the greater part of the thickness of the wall of the tubular member. The sealing member 10 and the sealing recess 11 are located within the other, remaining part. In this case it will be seen that the sealing member 10 extends from the end of the tubular member 13 having the recesses 15 and the sealing recess 11 is located in the end of the tubular member 13' having the projecting portions 14'.

Fig. 5 shows a similar arrangement to that of Fig. 4 (the same reference numerals being used where appropriate) except that the remaining parts of the adjacent end surfaces of the tubular members 13 and 13' not occupied by the projecting portions 14' or recesses 15 are so arranged as to provide a spigot 16' on the member 13' and a socket 17 on the member 13.

The tubular members need not, of course, be of square cross-section. They may, for example, be of circular cross-section.

In use, in a so-called "pi#e-jacking" process, a jacking pit is excavated to the desired level in the ground.

The jacking pit is made of a sufficient size to allow one tubular member constructed in accordance with the invention at a time to be lowered into the pit and be jacked into the ground. A first tubular member is lowered and jacked into the ground sufficiently to allow a second tubular member to be lowered into the pit and arranged so that its sealing member or sealing recess mates with the sealing recess or sealing member of the first tubular member. Projecting portions and corresponding recesses are also mated, if provided. A jacking load is then applied along the axis of both the tubular members so that the conduit formed by the first and second tubular members is jacked further into the ground. A third tubular member may then be lowered and the process repeated until a conduit of the desired length is inserted into the ground.

The jacking load is then removed. With the arrangement of the sealing member and the sealing recess, some relative longitudinal movement, which might take place on removal of the jacking load or arising from ground settlement, can be accomodated without destroying the seal. Relative lateral movement of the tubular members can be prevented or reduced by the presence of the projecting portions and corresponding recesses. Because the sealing member and the sealing recess are offset from the halfway position between the outer and inner surfaces of the tubular members, there is a sufficiently large, uninterrupted area available for the application and transmission, of the jacking load.

Alternatively to the above method, the tubular members may be arranged end to end to form a conduit before any of them is inserted into the ground, and then a jacking load applied to the rearmost tubular member.

The total length of the conduit may be of the order of 10m to 100m, and each tubular member may be of a length of, for example, from lm to 15m.

Claims

What we claim is:

1. A plurality of tubular members arranged end to end to form a conduit, at least one of the tubular members being provided at one end with a sealing member extending around the tubular member and projecting from the end surface of the tubular member in a direction substantially parallel to the axis of the tubular member and at least one other adjacent tubular member being provided at one end with a sealing recess extending around the tubular member, the sealing recess being arranged to accomodate at least a portion of the sealing member.

2. A plurality of tubular members as claimed in claim 1, wherein the sealing recess contains a plastic sealant material and a portion of the sealing member is embedded in the sealant material to form a seal.

3. A plurality of tubular members as claimed in claim 2, wherein the sealant material is a non-hardening material.

4. A plurality of tubular members as claimed in claim 2 or claim 3, wherein the sealant material is of such shear strength and capable of such adhesion to the material from which both the sealing member and the tubular members are made that relative movement of the sealing member and the sealing recess can take place without the sealant material de-bonding from the sealing member or the sealing recess.

5. A plurality of tubular members as claimed in any one of claims 2 to 4, wherein the sealant material can be inserted into the sealing recess without the application of heat.

6. A plurality of tubular members as claimed in any one of claims 2 to 5, wherein the sealant material is a petrolatum or rubber bitumen compound.

7. A plurality of tubular members as claimed in any one of claims 1 to 6, wherein the sealing member is made from a non-corrosive metal.

8. A plurality of tubular members as claimed in claim 7, wherein the metal is stainless steel, copper or aluminium.

9. A plurality of tubular members as claimed in any one of claims 1 to 6, wherein the sealing member is made from a plastics material.

10. A plurality of tubular members as claimed in any one of claims 1 to 9, wherein the tubular members are of precast concrete, and the sealing member is set in position, and the sealing recess is formed, during the casting process.

11. A plurality of tubular members as claimed in any one of claims 1 to 10, wherein the sealing member is so arranged that it leaves the end surface of its tubular member, and the sealing member is so arranged that it meets the end surface of its tubular member, at a position which if offset from the halfway position between the outer surface of the tubular member and its inner surface.

12. A plurality of tubular members as claimed in any one of claims 1 to 11, wherein the sealing recess is of substantially greater dimensions than the sealing member.

13. A plurality of tubular members as claimed in any one of claims 1 to 12, wherein the end surfaces of the tubular members are substantially planar and butt joints are formed between adjacent tubular members.

14. A plurality of tubular members as claimed in any one of claims 1 to 12, wherein the ends of adjacent tubular members are so shaped that spigot and socket joints are formed between them.

15. A plurality of tubular members as claimed in any one of claims 1 to 12, wherein at least one of the tubular members has at one end a plurality of projecting portions and at least one other adjacent tubular member has at one end a plurality of recesses, the projecting portions of the said one tubular member being arranged to mate with the recesses of the said adjacent tubular member to locate the tubular members relative to each other, and each of the projecting portions and each of the recesses having a pair of bearing surfaces, one bearing surface of each pair being arranged to resist movement by a mating tubular member relative to it in one direction around the periphery of its tubular member and the other bearing surface of each pair being arranged to resist movement of a mating tubular member relative to it in the opposite direction.

16. A plurality of tubular members as claimed in claim 15, wherein the tubular members are as claimed in any one of claims 2 to 40 s# United Kingdom Patent Specification No.

17. A plurality of tubular members as claimed in claim 15 or claim 16, wherein the projecting portions and their mating recesses extend in a direction normal to the axis of the tubular members over substantially the entire thickness of the walls of their respective tubular members.

18. A plurality of tubular members as claimed in claim 15 or claim 16, wherein the projecting portions and their mating recesses extend in a direction .normal to the axis of the tubular members over only nalf or the ,greater part of the thickness of the walls of their respective tubular members, and the sealing member and the sealing recess are located within the other, remaining part.

9. A plurality of tubular members as claimed in claim 18, wherein the Portion of the end surface extending over the other, remaining pat t OL t:le thickness is so arranged as to provide a spigot or a socket so that spigot and socket joints are formed between adjacent tubular members.

20. A plurality of tubular members as claimed in any one of claims 1 to 19, wherein there are two tubular members and the end surface of the wall of each tubular member at the opposite end to the sealing member and sealing recess, respectively, is planar.

21. A plurality of tubular members as claimed in any one of claims 1 to 19, which comprises three or more tubular members and wherein at least the or each intermediate tubular member has at one end a sealing member for insertion into a sealing recess of an adjacent tubular member and at its opposite end a sealing recess for the sealing member of an adjacent tubular member.

22. A tubular member for forming a conduit with one or more other such tubular members arranged end to end, the tubular member being provided at one end with a sealing member extending around the tubular member and projecting from the end surface of the tubular member in a direction substantially parallel to the axis of the tubular member and being provided at its other end with a sealing recess being arranged to accomodate at least a portion of the sealing member of another such adjacent tubular member.

23. A tubular member as claimed in claim 22, and suitable for use as one of the plurality of tubular members as claimed in any one of claims 1 to 21.

24. A tubular member substantially as hereinbefore described with reference to, and as shown in, Figs. 1 and 2, or Fig. 3, or Fig. 4 or Fig. 5 of the accompanying drawings.

25. A plurality of tubular members substantially as hereinbefore described with reference to, and as shown in, Figs. 1 and 2, or Fig. 3, or Fig. 4 or Fig. 5 of the accompanying drawings.

26 A method of forming a conduit using a plurality of tubular members as claimed in any one of claims 1 to 25.

27. A method as claimed in claim 26, wherein the tubular members arranged end to end are inserted into the grounds

28. A method as claimed in claim 27, wherein a first tubular member is urged into the ground, a second tubular member is then arranged end to end with the first tubular member so that its sealing member or sealing recess mates with the sealing recess or sealing member, respectively, of the first tubular member, and the second tubular member is urged into the ground.

29. A method as claimed in claim 28, wherein one or more successive tubular members are then inserted into the ground in a similar manner to the second tubular member until a conduit of the required length is formed in the ground.

30. A method as claimed claim 27, wherein at least first and second tubular members are arranged end to end before insertion of the first tubular member into the ground, and the said tubular members are then inserted into the ground by applying a load to the rearmost tubular member.

31.A method substantially as hereinbefore described with reference to Figs. 1 and 2, or Fig. 3, or Fig. 4 or Fig. 5 of the accompanying drawings.

32. A method as claimed in any one of claims 26 to 31, and also as claimed in any one of claims 1 to 29 of United Kingdom Patent Specification No. 2 185 277.