JP3721480B2 - Expansion / contraction segment for tunnel construction and its use - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tunnel construction segment that excavates in the ground and changes its cross section.
[0002]
[Prior art]
When changing the tunnel cross-section during conventional underground excavation, excavation work is performed in the cross-section change section, or ground is improved by chemical injection, etc., and then part of the existing tunnel is removed and the tunnel is We were doing construction work or using shield machines with different external shapes.
Recently, it has begun to be proposed to provide a widening function in the tail part, which is the segment assembly part of the shield machine, but the specific configuration has not yet been clarified, and there is a solution in implementing it. There is a problem that must be done, and it is not yet put into practical use.
[0003]
[Problems to be solved by the invention]
For this reason, conventionally, it has not been possible to continuously build tunnels with varying cross sections. In addition, the conventional methods have the following problems. In other words, when performing excavation work, it is necessary to secure a land for ground, and when the tunnel cover is deep, the excavation work itself becomes large-scale, which leads to a significant cost increase. . Moreover, in the case of construction work in the ground, in addition to the cost increase due to the ground improvement auxiliary method such as chemical injection, sufficient attention is required for safety. On the other hand, when using a shield machine having a different outer shape, it is necessary to manufacture a shield machine and install a new start shaft for starting another shield machine, which greatly increases the cost.
In addition, when the tailing part of the shield machine is provided with a widening function, the gap with the outer surface of the segment expands due to the cross-sectional change of the rear opening due to the widening of the tail part, and earth and sand and groundwater enter the tunnel from this gap. There was a problem. The present invention has been made to solve these problems.
[0004]
[Means for Solving the Problems]
The expansion / contraction segment of the present invention is used in a shield machine that excavates in the ground and constructs a tunnel, and is installed so as to surround the inside of the excavated tunnel, and its front and rear end faces are joined to the segments installed in the front and rear. In the tunnel construction segment used as a surface, in order to expand and contract the segment according to the expansion and contraction of the tail opening of the shield machine, a part of the segment can be slid in the direction perpendicular to the traveling direction of the shield machine. A shrinkable seal is provided at the joint, which is provided with a joint and follows a space generated in the joint as part of the segment slides.
In addition, a seal plate is provided that closes a space generated in the joint portion when the segment slides from the outside of the segment. In addition, you may provide the bellows seal which expands according to the sliding of a part of said segment, and the protection board for covering this bellows seal in the inner peripheral side of the said junction part.
Furthermore, a long hole having a length corresponding to the maximum widening amount is provided as a joint bolt hole with the front and rear segments on the joint surface of the expansion / contraction segment.
[0005]
The expansion / contraction segment of the present invention is constructed by assembling the tunnel expansion / contraction segment described in any one of the above inside the tail portion of a shield machine that intends to expand the tunnel more than before, by using an existing adjacent segment and bolt. When the shield machine is propelled and the expansion / contraction movement segment overlaps with the tail seal part of the shield machine and comes to a position where sealing is possible, the expansion / contraction movement segment and the existing adjacent segment are joined. The bolt that has been loosened is loosened, and the expansion / contraction movement segment is slid by slide jack until it substantially matches the widening of the tail portion of the shield machine.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
FIG. 1 is a perspective view of the entire expansion / contraction segment showing one embodiment of the present invention. This segment is composed of the left and right segment digits and the expansion / contraction moving segment 1 constituting a part of the upper and lower segment digits and the central segment 2 constituting the upper and lower segment digits. The expansion / contraction movement segment 1 and the central segment 2 are each provided with one joint 3 at the left and right symmetrical part on the left side of the present enlargement / reduction segment and one joint 3 at the right and left symmetrical part, respectively. 3 is fitted so that the expansion / contraction moving segment 1 can slide to the left and right (direction perpendicular to the traveling direction of the shield machine) with respect to the central segment 2. Furthermore, as an expansion / contraction moving device that slides the expansion / contraction movement segment 1, for example, a slide jack 5 is detachably passed between the right and left expansion / contraction movement segments 1. Here, slide jacks are provided in two upper and lower stages. In addition, each joint 3 between the expansion / contraction movement segment 1 and the central segment 2 can be contracted in order to fill a space generated outside the expansion / contraction segment when the expansion / contraction movement segment 1 moves away from the central segment 2. A simple seal bag 4, for example, a water bag capable of adjusting water pressure is disposed. In addition to this, on the front and rear end faces of the expansion / contraction moving segment 1 and the central segment (hereinafter referred to as the joining surface), there are bolt holes 6 used for joining the present segment and the adjacent segments before and after the entire circumference. Provided. The length in the longitudinal direction of the bolt hole 6 is set equal to, for example, the amount of movement of the expansion / contraction movement segment 1.
[0007]
FIG. 2 is an enlarged view of the vicinity of the joint portion 3 of FIG. 1 when the entire segment is widened by sliding the expansion / contraction moving segment 1 of FIG. 1 outward. As the expansion / contraction movement segment 1 slides in the outer direction, a space is created between the expansion / contraction movement segment 1 and the central segment 2 in this segment, and the space is as shown in FIG. It is always filled with the seal bag 4 to which water pressure is applied, and is adjusted so as not to generate a gap.
[0008]
Next, the usage method of this expansion / contraction segment is demonstrated. The expansion / contraction segment is first assembled as shown in FIG. 1 inside the tail of the shield machine where the tunnel is to be expanded. Although not shown in the drawing, this segment is joined to the existing adjacent segment by a bolt in this state. Next, when the shield machine is propelled and this expansion / contraction segment overlaps the tail seal part of the shield machine and comes to a position where sealing is possible, once the joint bolt with the previous segment of this expansion / contraction segment is loosened, slide The expansion / contraction movement segment 1 is slid by the jack 5 until it substantially coincides with the widening of the shield machine tail. At this time, among the spaces generated in the joint portion 3 between the expansion / contraction movement segment 1 and the central segment 2, the space generated on the outer surface of the expansion / contraction segment opposes the external pressure on the seal bag 4 built in the central segment 2. Water pressure is injected to fill the space, preventing sediment and groundwater from entering the tunnel through the gap.
[0009]
Before the expansion / contraction movement segment 1 is moved, the joint bolt with the existing segment that is in contact with one end of the bolt long hole 6 of the expansion / contraction segment is moved to the bolt long hole 6 after the maximum movement of the expansion / contraction movement segment 1. At the end, the bolt will be tightened again. That is, by adopting the bolt long holes 6, it is possible to save the trouble of removing and retightening the bolts each time the expansion / contraction movement segment 1 is expanded or contracted.
[0010]
In addition, as shown in FIG. 2, when the existing adjacent segment is a segment surrounded by a solid line and a two-dot chain line, and when this expansion / contraction segment joined to this existing segment is widened after joining, The joint surface of this expansion / contraction segment is made larger than the joint surface of the existing segment of the type that does not widen so that an overlapping joint portion (A portion in FIG. 2) is secured around the joint surface of these segments. Intrusions inside the earth and sand and groundwater segments.
The example of the widening of the present enlarged / reduced segment has been described above. However, it can be easily imagined that the oppositely widened segment is reduced to the original.
[0011]
Embodiment 2
FIG. 3 is a perspective view of the entire expansion / contraction segment showing another embodiment of the present invention. In this example, the configuration of the joint portion 3 between the expansion / contraction moving segment 1 and the central segment 2 is slightly different from the first embodiment described above. That is, the seal plate 7 that overlaps the left and right expansion / contraction movement segments 1 with the central segment 2 as the center is provided outside the expansion / contraction segment 1 and the expansion / contraction movement segment 1 is widened. And the space generated at the joint portion 3 with the central segment 2 is closed from the outside. In addition, the sealing function can be further improved by providing the expansion / contraction moving segment 1 with the sealing material 8 that slides between the sealing plate 7 and the central segment 2.
[0012]
Embodiment 3
FIG. 4 is a perspective view of the entire expansion / contraction segment showing still another embodiment of the present invention. As can be seen from the figure, this is a modification of the previous embodiment 2, in which a bellows seal 9 is provided on the inner peripheral side of the joint portion 3 between the expansion / contraction movement segment 1 and the central segment 2 and the expansion / contraction movement segment 1 slides. Accordingly, the bellows seal 9 is widened. In this case, it is preferable to pass a protective plate 10 for covering the bellows seal 9 between the expansion / contraction moving segment 1 and the central segment 2.
[0013]
In each of the above-described embodiments, the rectangular expansion / contraction segment has been described, but the shape of the segment may be an ellipse or a circle. Moreover, although the junction part 3 provided in the symmetrical part of a segment girder was comprised from 2 sets of the left side and the right side of an expansion / contraction segment in this Example, it may be made into 1 set or 2 sets or more.
[Brief description of the drawings]
FIG. 1 is a perspective view of an entire segment showing an example of an embodiment of the present invention.
FIG. 2 is an enlarged view of the vicinity of a joint portion 3 when the entire segment is widened by sliding the expansion / contraction moving segment 1 of FIG. 1 outward.
FIG. 3 is a perspective view of the entire segment showing another embodiment of the present invention.
FIG. 4 is a perspective view of the entire segment showing still another embodiment of the present invention.
[Explanation of symbols]
1: Expansion / contraction movement segment 2: Central segment 3: Joint part 4 of expansion / contraction movement segment 1 and central segment 2: Seal bag 5: Expansion / contraction movement device 6: Slotted hole 7 for joint bolt: Seal plate 8: Seal material 9: Bellows Seal 10: Protection plate

Claims (5)

Tunnel construction that is used in shield machines that dig underground and construct tunnels, and is installed so as to surround the inside of the excavated tunnel, and its front and rear end faces are used as joint surfaces with the front and rear segments. In order to expand and contract the segment according to the expansion and contraction of the opening of the tail part of the shield machine, the segment is provided with a joint that allows a part of the segment to slide in a direction perpendicular to the traveling direction of the shield machine. An expansion / contraction segment for tunnel construction, characterized in that a contractible seal according to a space generated in the joint portion when a part of the joint portion is slid is disposed at the joint portion . 2. The expansion / contraction segment for tunnel construction according to claim 1, further comprising: a seal plate that closes a space generated in a joint portion as a part of the segment slides from the outside of the segment. 3. The tunnel construction according to claim 2, wherein a bellows seal that widens as a part of the segment slides and a protective plate for covering the bellows seal are provided on the inner peripheral side of the joint. Expansion / contraction segment. As fastening bolt hole of the front and rear segments on the bonding surface of the scaling segments, according to any one of claims 1 to 3, characterized in that the elongated hole having a length corresponding to the maximum widening amount provided Expansion / contraction segment for tunnel construction. The expansion / contraction segment for tunnel construction according to any one of the preceding claims is assembled inside a tail portion of a shield machine where a tunnel is to be expanded more than before, and is joined to an existing adjacent segment by a bolt. When the shield machine is propelled and the expansion / contraction movement segment overlaps the tail seal portion of the shield machine and comes to a position where sealing is possible, the bolt that joined the expansion / contraction movement segment and the existing adjacent segment is removed. A method of using an expansion / contraction segment for tunnel construction, wherein the expansion / contraction moving segment is slid by loosening and a slide jack until the expansion / contraction movement segment substantially coincides with the widening of the tail portion of the shield machine.

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