CA1169258A

CA1169258A - Tunnel linings

Info

Publication number: CA1169258A
Application number: CA000380315A
Authority: CA
Inventors: Rupert J.S. Mcbean
Original assignee: Charcon Tunnels Ltd
Current assignee: Charcon Tunnels Ltd
Priority date: 1981-06-22
Filing date: 1981-06-22
Publication date: 1984-06-19

Abstract

Abstract TUNNEL LININGS

A disclosure related to a tunnel lining made up of a number of side-by-side rings each having a plurality of arcuate segments generally smooth internal surface forming the invert of the tunnel and secured together end-to-end by overlapping tensile hoops projecting from the respective segment ends and retaining device is driven into the overlapping hoops to hold the segment ends together in compression and an arch of further segments such as bolted straight recessed segments completing the ring.

Description

1 ~ 6 ~

_eld of the Inven-tion The invention relates to tunnel linings.

Background of the Invention Descri~tion of the Prior Art U.K. Patent No. 14462~02 describes and illustrates a tunnel llning consisting of rings of arcuate segments a nuinber of which are preformed, internally smdokh segments to provide the lower or invert of the lining and a num~er of which have recesses on the inner surfaces and are fixed toge-ther by bolts to form the upper part of the lining. The smooth segments are in-terconnected by simple dowel connections between adiacent circumferentlal ends of the segments which locate the ends of the segments in register with one another but do not secure the ends of the segments together. It has been found that when such a lining is erected behind a tunnelling shield, and as the shield is withdrawn from the lining there is a tendency for the smooth invert segments to drop away from the other segments because the dowel connections do not hold the segments positively in place. It has also been found with this form of tunnel lining ring that as the loads on the tunnel lining increase over the mon-ths after 5 ~

construction, the lining tends to squat in the vertical plane and to adopt an increasing out of circular form. The simple dowel connections between the smooth segments of the invert are not cap-able of resistiny such squat.
United Kingdom Patent 2,004,931 describes and illustrates a tunnel lining comprising rings of arcuate segments of smooth internal surface which are locked positively together at their circumferential ends by tapered pins driven into recesses in the adjacent segment ends through overlapping tensile hoops bridging the re esses to lock the segment ends together in compression.
This construction can be built to true circular form and since the segments are locked together there is no risk of the lowermost segments dropping away after extraction of the shield and so the circularity of the ring is maintained as the loads on the ring increase.
However, in certain conditions, neither of the above forms of lining may be considered suitable and it is an object of this invention to provide a lining which preserves the rigid invert structure of United Kingdom Patent 2,004,931 whilst per-mitting an 01ement of choice for the remaining part of the lining.
Summary of the Invention The invention provides a tunnel lining comprising a number of side-by-side sections each having a pluraltty of arcuate segments of generally smooth internal surface forming a lower part of the section with the segments being secured together end-to-end by overlapping tensile hoops projecting from the respective segment end and retaining devices driven into the overlapping hoops and an arch of a further form of segment bridging the upper ends of the ~ ~ 6~3258 lower part of the section, the arch comprising a plurality of arcuate segments having end flanges, bolts securing the end flanges of adjacent segments together, sockets in the upper ends of the segments of the lower part of the section and further bolts extend-ing through the flanges at the lower ends of the arch and screwed into the sockets in the upper ends of the lower part of the section to secure the flanges to said upper ends.
Brief Description of the DrawingS
Figure 1 is an end view of a section of a tunnel lining;
and Figure 2 is a section along the line 2 2 on Figure 1.
Description of the Preferred Embodiments Referring firstly to Figure 1 of the drawings, the tunnel lining section shown constitutes one of a number of sections laid along the tunnel and comprises a lower part indicated general-ly by the reference numeral 10 having three (or optionally more) arcuate concrete smooth internal surface tunnel lining segments Ll laid end to-end around the lower part of the tunnel. The joints indlcated at 12 between adjacent ends of the segments 11 are of the ~orm described and illustrated in United Kingdom Patent

2,00~r931. sriefly, each segment end has a pair of spaced semi-cylindrical grooves e~tending partway across the segment `~ ~6~25~3 end from the inner side thereof. One of -the grooves has a pair of tensile hoops bridging the groove and projecting from the segment end to receive a corresponding hoop on the adjacent segment and the other groove has a single tensile hoop projecting from the segmen-t end to engage be-tween a corresponding pair of hoops on the other segment end. Either tapered pins or equivalent fastening devices are driven into the overlapping hoopsto draw and hold the segment ends together in compression. Where required a waterproof membrane or o-ther sealing element may be disposed between the adjacent ends of the segments. The resulting assembly of seyments 11 provides a smooth internal lower surface for the tunnel lining.
15The segment ends 13 at the upper ends of the lower par-t 10 of the lining each have a pair of spaced ~-cast-in ~rew threaded sockets 14 and the upper arch of the lining comprises a pair of further arcuate concrete lining segmen-ts 15. The lower ends 16 of the arch of further segments are formed with in-ternal flanges 17 through which bolts (not shown) extend into the sockets 14 -to secure the lower ends of the segments 16 to the upper ends 14 of the segments 11. The adjacent ends of the two seyments 15 at -the -top of the lining are each formed with further flanges 18 which are bolted toyether with a ke~ segment 19 between the ends of -the segments, ~ 3~

Thus the upper part of the lining does not have a smooth internal surface as provided by the lower part of the lining but, since the entire or at least the main flow of fluid through the lining will take place through the lower part of the lining only the lower part of the lining need have a smooth internal surface. The upper part of the lining can be formed from any conventional construction of which the bolted lining system just described is but one example. In the case where the lining is not intended for waterflow but for purposes such as supporting the ground in a railway tunnel/ a simple arch construction may be used for supporting the tunnel roof instead of the lining arrangement.
The tunnel lining segments can be secured together along the tunn~l by any convenient system such as that described and illustrated in our United Kingdom patent No. 2,004,931.
It will be understood that the number of smooth inner surface lining segments provided in the lower part of the lining and the construction of the upper part of the lining can be varied from that described above to suit the requirements of the particular lining to be constructed.

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Claims

THE EMBODIMENT OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A tunnel lining comprising a number of side-by-side sections each having a plurality of arcuate segments of generally smooth internal surface forming a lower part of the section with the segments being secured together end-to-end by overlapping tensile hoops projecting from the respective segment end and retaining devices driven into the overlapping hoops and an arch of a further form of segment bridging the upper ends of the lower part of the section, the arch comprising a plurality of arcuate segments having end flanges, bolts securing the end flanges of adjacent segments together, sockets in the upper ends of the segments of the lower part of the section and further bolts extending through the flanges at the lower ends of the arch and screwed into the sockets in the upper ends of the lower part of the section to secure the flanges to said upper ends.