Prefabricated element for wall construction
United States Patent 3886752
An element for use in manufacturing a fluid-tight wall comprising a body of concrete with an impermeable sheet metal member extending through the body to the lateral edges thereof. In manufacturing a wall, the edges of the sheet metal members of adjacent elements are connected together, e.g. by welding.
US Patent References:
/1221067.html
McBean - April 1917 - 1221067
Reinforced-concrete conduit
Scofield - July 1920 - 1346687
Concrete pressure-pipe joint
Phelps - December 1926 - 1609660
Construction panel
Berliner - May 1960 - 2934934
Shield segment for covering the inner wall of the tunnel made of composite shell units
Akita et al. - December 1968 - 3415063
/1221067.html
McBean - April 1917 - 1221067
Reinforced-concrete conduit
Scofield - July 1920 - 1346687
Concrete pressure-pipe joint
Phelps - December 1926 - 1609660
Construction panel
Berliner - May 1960 - 2934934
Shield segment for covering the inner wall of the tunnel made of composite shell units
Akita et al. - December 1968 - 3415063
Application Number:
05/419926
Publication Date:
06/03/1975
Filing Date:
11/29/1973
View Patent Images:
Export Citation:
Assignee:
V, B. S. (Grenoble, FR)
Primary Class:
Other Classes:
285/290.400
International Classes:
E21D11/04; E21D11/38; E21D11/08
Field of Search:
52/432,303 61/43,45R 285/288,297
Primary Examiner:
Wolfe, Robert L.
Assistant Examiner:
Corbin, David H.
Attorney, Agent or Firm:
Cameron, Kerkam, Sutton, Stowell & Stowell
Claims:
What is claimed is
1. A prefabricated element for use in the construction of a fluid-tight wall comprising a plurality of such elements positioned side by side with their lateral faces in contact, said element comprising:
2. A prefabricated element for use in the construction of a fluid-tight wall comprising a plurality of such elements positioned side by side with their lateral faces in contact, said element comprising:
1. A prefabricated element for use in the construction of a fluid-tight wall comprising a plurality of such elements positioned side by side with their lateral faces in contact, said element comprising:
2. A prefabricated element for use in the construction of a fluid-tight wall comprising a plurality of such elements positioned side by side with their lateral faces in contact, said element comprising:
Description:
The invention relates to a prefabricated element for use in constructing a wall, and to a process of constructing a fluid-tight wall from such elements.
It has become customary to construct tunnels with a lining formed by progressively laying prefabricated reinforced concrete arch-stones forming successive rings which closely follow the drilling front. This technique presents problems when there are external water inflows. Attempts have been made to inject mortar or sealing products behind the wall but this process is expensive and its efficiency uncertain. Equally, injection of longitudinal and circumferential joints between the arch-stones cannot guarantee fluid-tightness, especially over a long period, particularly if small movements of the surrounding rock mass, due to slow tectonic displacements or to long-term decompression of the rock, tend to open the joints slightly. Further vibrations created by the passage of rail or road traffic along the tunnel can only impair the fluid-tightness of the tunnel.
When the gallery is subjected to large pressurized water inflows, as may for example be the case with sub-marine tunnels, fluid-tightness of a lining formed of normal prefabricated arch-stones is practically impossible.
In accordance with one aspect of the invention, there is provided a prefabricated element for use in the construction of a fluid-tight wall comprising a plurality of such elements positioned side by side with their lateral faces in contact, the element comprising an impermeable sheet member embedded in moulded material and adhering thereto, wherein said sheet member is provided around the whole of its periphery with a rim which is tangential to the lateral faces of the element such that, when two such elements are positioned side by side, said rims of the sheet members of the elements contact each other.
In accordance with another aspect of the invention, there is provided a process of manufacturing a fluid-tight wall, comprising forming a plurality of elements of moulded material, each containing an impermeable sheet member embedded in the moulded material and projecting from the edges of the element, placing said elements side by side to form the wall, and connecting the corresponding edges of said sheet members of adjacent elements by fluid-tight connection means.
The invention will be more fully understood from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a cross-section through a prefabricated wall;
FIG. 2 is a longitudinal section along the line II--II of FIG. 1;
FIG. 3 is a perspective view of a prefabricated element in accordance with the invention;
FIG. 4 is a perspective view of an impermeable sheet prior to incorporation in a prefabricated element; and
FIG. 5 is a detailed section of the junction between two prefabricated elements.
As shown in FIGS. 1 and 2 a tunnel is formed of a tubular wall 1 consisting of prefabricated arch-stones, a mortar packing 2 being provided between wall 1 and rock 3 after the wall has been placed in position. Wall 1 consists of a plurality of prefabricated arch-stones 10 joined side by side.
One of these arch-stones is shown in perspective in FIG. 3. It has an intrados face 11 and and extrados face 12, in the form of curved rectangles, two longitudinal lateral faces 13 and two circumferential lateral faces 14. As shown in more detail in FIG. 5, each element is made of moulded concrete 4 and includes a metal sheet member or plate 5 embedded in the concrete.
FIG. 4 shows plate 5 prior to embedding.
It will be seen that plate 5 has a central portion 50 which extends parallel to the intrados and extrados faces of the arch-stone, and inclined lateral faces 51 each of which terminates in a rim 52 perpendicular to portion 50. Plate 5 may advantageously be made by stamping.
As shown in FIG. 5, the central portion 50 of plate 5 is positioned substantially in the middle of the arch-stone and the ends of faces 51 project from the concrete in a chamfer 110 formed along the edges of intrados face 11, which are so arranged that rim 52 is in the plane of the joint. When two adjacent arch-stones are placed in position, rims 52 thus come into contact with each other inside a groove formed by the corresponding chamfers 110 of the two arch-stones.
Contacting rims 52 of two adjacent arch-stones may be welded by any manual or automatic means, for example seam-welding, or possibly stuck together with a suitable adhesive.
If the extenal water inflows are large during construction of the tubular wall 1, a tube 6 may be provided on one side of the joint, passing through plate 5 and welded to the latter, and opening into a cavity 7 formed along the joints. It is thus possible to effect a temporary or permanent injection of mortar or any other fluid-tight composition into the thickness of the joint between the arch-stones which will enable the rims 52 of the plates 5 to be welded dry. Tube 6 is subsequently blocked.
Once welding has been carried out, it only remains to fill the groove formed by chamfers 110 by a carefully inserted mortar.
In order to increase the adherence of plate 5 to the concrete, plate 5 is provided with welded pins 53 or any other anchoring means. When the arch-stone is made of reinforced concrete, certain reinforcements could also be welded to plate 5.
Plate 5 normally only has a sealing role, strains being absorbed by the concrete, whether reinforced or otherwise. A thin plate may therefore be used. However, it is obviously possible for the plate to participate in the strengthening of the arch-stone, causing it to act as a reinforcement in the concrete. In this case, the characteristics of the plate must naturally be calculated according to the reinforcement required.
The dimensions of chamfers 110 should be small enough to ensure efficient support on the contacted faces of the arch-stones. Moreover, as shown in FIG. 5, the lateral faces of each arch-stone are advantageously provided with shoulders designed to interlock when the arch-stones are placed in position. Plates 5 may also facilitate the location of accessories in the arch-stones. For example, tubes passing through the plate and welded to the latter may be arranged in certain locations to permit injection of the mortar packing 2 between the rock and wall 1.
It will be seen that the above-described prefabricated elements permit easy construction of a fluid-tight tunnel wall, since the final tunnel wall comprises a continuous metal tube embedded in concrete. As a result of this embedding, the whole of the plate is protected from corrosion and also from fire, which is always possible in the case of a tunnel taking rail or road traffic.
It will be noted that the shape given to the edges of the plates permits them a certain degree of deformation. Because of this, there is no longer a risk of vibrations opening the joints between the elements and impairing the fluid-tightness. Other plate shapes capable of absorbing slight displacements could alternatively be used.
The invention is not intended to be limited to the details of the embodiment described above, but on the contrary embraces all its modifications. Thus the metal plate could have another form or be replaced by a sheet of impermeable material which is sufficiently adherent to the moulded material forming the prefabricated element. Moreover, it is not necessary for the plate to be smooth. It could on the contrary have undulations or unevennesses favouring adherence to the concrete.
The element could itself have other forms. Moreover, such prefabricated elements could be used in other applications than tunnels, for example, in a fluid-tight floor.
Finally, it will be noted that the interposition of the plate in the moulded material does not prevent pre-stressing of the concrete.
It has become customary to construct tunnels with a lining formed by progressively laying prefabricated reinforced concrete arch-stones forming successive rings which closely follow the drilling front. This technique presents problems when there are external water inflows. Attempts have been made to inject mortar or sealing products behind the wall but this process is expensive and its efficiency uncertain. Equally, injection of longitudinal and circumferential joints between the arch-stones cannot guarantee fluid-tightness, especially over a long period, particularly if small movements of the surrounding rock mass, due to slow tectonic displacements or to long-term decompression of the rock, tend to open the joints slightly. Further vibrations created by the passage of rail or road traffic along the tunnel can only impair the fluid-tightness of the tunnel.
When the gallery is subjected to large pressurized water inflows, as may for example be the case with sub-marine tunnels, fluid-tightness of a lining formed of normal prefabricated arch-stones is practically impossible.
In accordance with one aspect of the invention, there is provided a prefabricated element for use in the construction of a fluid-tight wall comprising a plurality of such elements positioned side by side with their lateral faces in contact, the element comprising an impermeable sheet member embedded in moulded material and adhering thereto, wherein said sheet member is provided around the whole of its periphery with a rim which is tangential to the lateral faces of the element such that, when two such elements are positioned side by side, said rims of the sheet members of the elements contact each other.
In accordance with another aspect of the invention, there is provided a process of manufacturing a fluid-tight wall, comprising forming a plurality of elements of moulded material, each containing an impermeable sheet member embedded in the moulded material and projecting from the edges of the element, placing said elements side by side to form the wall, and connecting the corresponding edges of said sheet members of adjacent elements by fluid-tight connection means.
The invention will be more fully understood from the following description of an embodiment thereof, given by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a cross-section through a prefabricated wall;
FIG. 2 is a longitudinal section along the line II--II of FIG. 1;
FIG. 3 is a perspective view of a prefabricated element in accordance with the invention;
FIG. 4 is a perspective view of an impermeable sheet prior to incorporation in a prefabricated element; and
FIG. 5 is a detailed section of the junction between two prefabricated elements.
As shown in FIGS. 1 and 2 a tunnel is formed of a tubular wall 1 consisting of prefabricated arch-stones, a mortar packing 2 being provided between wall 1 and rock 3 after the wall has been placed in position. Wall 1 consists of a plurality of prefabricated arch-stones 10 joined side by side.
One of these arch-stones is shown in perspective in FIG. 3. It has an intrados face 11 and and extrados face 12, in the form of curved rectangles, two longitudinal lateral faces 13 and two circumferential lateral faces 14. As shown in more detail in FIG. 5, each element is made of moulded concrete 4 and includes a metal sheet member or plate 5 embedded in the concrete.
FIG. 4 shows plate 5 prior to embedding.
It will be seen that plate 5 has a central portion 50 which extends parallel to the intrados and extrados faces of the arch-stone, and inclined lateral faces 51 each of which terminates in a rim 52 perpendicular to portion 50. Plate 5 may advantageously be made by stamping.
As shown in FIG. 5, the central portion 50 of plate 5 is positioned substantially in the middle of the arch-stone and the ends of faces 51 project from the concrete in a chamfer 110 formed along the edges of intrados face 11, which are so arranged that rim 52 is in the plane of the joint. When two adjacent arch-stones are placed in position, rims 52 thus come into contact with each other inside a groove formed by the corresponding chamfers 110 of the two arch-stones.
Contacting rims 52 of two adjacent arch-stones may be welded by any manual or automatic means, for example seam-welding, or possibly stuck together with a suitable adhesive.
If the extenal water inflows are large during construction of the tubular wall 1, a tube 6 may be provided on one side of the joint, passing through plate 5 and welded to the latter, and opening into a cavity 7 formed along the joints. It is thus possible to effect a temporary or permanent injection of mortar or any other fluid-tight composition into the thickness of the joint between the arch-stones which will enable the rims 52 of the plates 5 to be welded dry. Tube 6 is subsequently blocked.
Once welding has been carried out, it only remains to fill the groove formed by chamfers 110 by a carefully inserted mortar.
In order to increase the adherence of plate 5 to the concrete, plate 5 is provided with welded pins 53 or any other anchoring means. When the arch-stone is made of reinforced concrete, certain reinforcements could also be welded to plate 5.
Plate 5 normally only has a sealing role, strains being absorbed by the concrete, whether reinforced or otherwise. A thin plate may therefore be used. However, it is obviously possible for the plate to participate in the strengthening of the arch-stone, causing it to act as a reinforcement in the concrete. In this case, the characteristics of the plate must naturally be calculated according to the reinforcement required.
The dimensions of chamfers 110 should be small enough to ensure efficient support on the contacted faces of the arch-stones. Moreover, as shown in FIG. 5, the lateral faces of each arch-stone are advantageously provided with shoulders designed to interlock when the arch-stones are placed in position. Plates 5 may also facilitate the location of accessories in the arch-stones. For example, tubes passing through the plate and welded to the latter may be arranged in certain locations to permit injection of the mortar packing 2 between the rock and wall 1.
It will be seen that the above-described prefabricated elements permit easy construction of a fluid-tight tunnel wall, since the final tunnel wall comprises a continuous metal tube embedded in concrete. As a result of this embedding, the whole of the plate is protected from corrosion and also from fire, which is always possible in the case of a tunnel taking rail or road traffic.
It will be noted that the shape given to the edges of the plates permits them a certain degree of deformation. Because of this, there is no longer a risk of vibrations opening the joints between the elements and impairing the fluid-tightness. Other plate shapes capable of absorbing slight displacements could alternatively be used.
The invention is not intended to be limited to the details of the embodiment described above, but on the contrary embraces all its modifications. Thus the metal plate could have another form or be replaced by a sheet of impermeable material which is sufficiently adherent to the moulded material forming the prefabricated element. Moreover, it is not necessary for the plate to be smooth. It could on the contrary have undulations or unevennesses favouring adherence to the concrete.
The element could itself have other forms. Moreover, such prefabricated elements could be used in other applications than tunnels, for example, in a fluid-tight floor.
Finally, it will be noted that the interposition of the plate in the moulded material does not prevent pre-stressing of the concrete.