JP3335453B2 - Tunnel wall - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel wall formed by arranging a plurality of segments in an annular shape.

[0002]

2. Description of the Related Art In the construction of a tunnel, it is common to lay a tunnel by assembling a segment on the inner wall surface of a digging pit formed by digging the ground to form a ring-shaped tunnel wall. is there. The tunnel wall is subjected to a compressive force toward the center in the cross-sectional direction due to earth pressure or water pressure from the inner wall surface of the excavation pit, thereby generating an axial force between the segments connected in the circumferential direction of the tunnel wall, thereby causing deformation resistance. Is to be expressed. Further, in places where the external force applied to the wall is not uniform, it is necessary to reinforce the deformation resistance of the wall. For this reinforcing means, a segment having a PC steel wire insertion hole is used. To construct a wall to introduce prestress in the circumferential direction of the wall.

[0003]

By the way, in the case of the tunnel wall, the action of the external force is mainly in the vertical direction, and as shown in FIG. , A positive bending force (tensile force on the inner surface and a compressive force on the outer surface) is applied to the segments located above and below the tunnel, and a negative bending force (outer surface) is applied to the segments located on both sides. Is applied to the inner surface of the tunnel wall. On the other hand, the pre-stress force applies a pre-stress which is effective to each of the segments circumferentially connected to the entire tunnel wall. In particular, the segments on both sides are required to withstand the negative bending force from the external force and to suppress the joints and apertures, which has affected the strength and performance of the entire tunnel wall.

Further, since the state of insertion of the PC steel wire in the insertion hole cannot be checked from the inside of the wall, it is troublesome to insert the PC steel wire into the insertion hole and to tension the PC steel wire. In addition, there are other inconveniences such as difficulty in maintenance of PC steel wire such as application of rust preventive material after completion of construction of the wall.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a tunnel wall having high strength and advantageous for construction and maintenance.

[0006]

According to the tunnel wall of the present invention, a plurality of segments are arranged in a lengthwise direction and a circumferential direction of a tunnel along an excavation surface in a tunnel formed by excavating underground. A tunnel wall to be formed, wherein each segment is formed with a groove extending in a circumferential direction of the tunnel, and is arranged along the length of the tunnel across the groove, and An inner peripheral side locking rod and an outer peripheral side locking rod which are arranged to be displaced in the inner and outer peripheral directions are provided, and each of these segments is arranged so that the groove is continuous in the circumferential direction, and forms one unit of the tunnel wall. The segment for each unit is locked by the inner circumferential side locking rod or the outer circumferential side locking rod, is annularly arranged in the groove of each segment and is restrained by a wire tightened, and the wire is Smell above and below the tunnel Locked to the inner peripheral side latching bar was that it is locked to the outer peripheral side latching rod in the left and right to the solutions of the problems.

[0007]

According to the tunnel wall of the present invention, a negative bending force acts on each segment by the prestressing force introduced into one unit of the tunnel wall. The negative bending force is applied to the uppermost portion and the lowermost portion of the tunnel wall. Is largest and acts the least on the left and right sides of the tunnel wall, and prestress is effectively introduced for each part of the ring.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 denotes a tunnel wall of the present invention, and the tunnel wall 1 has six segments 2.
A ring-shaped unit formed by connecting 2... In the circumferential direction is connected in a large number in the axial direction. The one unit constituting the tunnel wall 1 is composed of segments 21 and 21 arranged vertically opposed to each other and two segments 21 and 21 arranged between the segments 21 and 21 on the left and right.
Prestress introduced by two PC steel wires K (wires), which are composed of a total of four segments 22 connecting the two members 21 in the circumferential direction, and arranged over the entire circumference of one unit in the circumferential direction. Each segment 2 is restrained by force.

As shown in FIGS. 2 to 4, each of the segments 2, 2... Constituting the tunnel wall 1 has a groove 3 extending in the circumferential direction of the tunnel wall 1 at the center in the width direction on the inner surface side. And an inner circumferential side locking rod 4 that is arranged in the length direction of the tunnel wall 1 across the groove 3 and is displaced in the inner and outer circumferential directions of the tunnel wall 1.
In addition, a large number of outer peripheral locking bars 5 are provided in the circumferential direction of the segment 2. On the circumferential end face 6 of the segment 2, a joining metal fitting 7 for joining circumferentially adjacent segments 2 and 2 is provided. A joining bolt insertion hole 9 (not shown) for joining the segments 2 and 2 adjacent in the axial direction is opened in the axial end face 8 of the segment 2. This insertion hole 9 is penetrated between the axial end face 8 and the groove 3. The groove 3 is formed by joining the segments 2.
Are continuous with each other between the adjacent segments 2, and extend over the entire inner peripheral side of the unit.
A steel wire K is provided.

The inner peripheral locking rod 4 and the outer peripheral locking rod 5 are
Both are arranged and fixed in parallel to the width direction of the segment 2 between the inner side surfaces 10 facing the groove 3. As shown in FIG. 5, a recess 11 is provided on the inner side surface 10 of the groove 3, and the inner peripheral locking bar 4 and the outer peripheral locking bar 5 have their ends inserted into the recess 11. At the same time, the end face 12 abutting on the recess 11 is bonded with an epoxy resin or the like. The inner locking rod 4 and the outer locking rod 5 come into contact with the jack of the shield machine when the tunnel wall 1 is constructed by the shield machine, and bear the forward reaction force of the shield machine.

As shown in FIGS. 1 and 4, the PC steel wire K is engaged with the inner peripheral locking rod 4 above and below the tunnel wall 1 and is engaged with the outer peripheral locking rod 5 on the same left and right sides. It is stopped and is annularly arranged in the groove 3 of each segment 2. More specifically, the annularly arranged PC steel wire K is connected to the tunnel wall 1.
Are locked outside the inner circumferential locking rod 4 at the uppermost and lowermost segments 21, and are positioned outside the inner circumferential locking rod 4 on the side close to the upper and lower segments 21 in each of the left and right segments 22. The upper and lower segments 21 are hooked and bridged between the inner circumference locking rod 4 and the outer circumference locking rod 5 at the center.
The outer side of the outer peripheral locking rod 5 is locked on the side separated from the outer peripheral locking rod 5, and the whole is tightened and held at a tightening position (not shown).

The tunnel wall 1 is, as shown in FIG.
A positive bending force acts on the upper and lower segments 21 due to an external force such as earth pressure mainly acting in the vertical direction from the ground T, and a negative bending force is generated on each of the left and right segments 22.
Due to the restraining force of the steel wire K, a negative bending force is applied to all the segments 21 and 22. The negative bending force acting by the restraining force of the PC steel wire K is large if the PC steel wire K is disposed inside the segment 2 and small if the PC steel wire K is outside the segment 2. In the segment 22, it is large at the portion near the segment 21 and small at the portion separated from the segment 21. That is, in the tunnel wall 1, it is large at the uppermost portion and the lowermost portion, and conversely smaller at both the left and right ends.

Therefore, according to the tunnel wall 1,
At least in the portion of each segment 22 located on the left and right that is separated from the upper and lower segments 21, the negative bending force due to the pre-stress is smaller than that of the upper and lower segments 21, and the negative bending force due to the vertical external force such as earth pressure is reduced Since the effective negative bending force which is the sum of the negative bending force due to the prestress can be suppressed, the strength of the tunnel wall 1 is improved. Further, since the PC steel wire K is in the groove 3 in each segment 2 and is visible from the inner surface of the tunnel wall 1, it is advantageous for arranging and maintaining the PC steel wire K.

The inner peripheral locking rod 4 and the outer peripheral locking rod 5 may be members having shapes other than the rod shape. Further, as shown in FIG. 6, the inner peripheral locking rod 4 and the outer peripheral locking rod 5 may be fixed to the segment 2 by burying their respective tips in the segment 2.

[0015]

As described above, according to the tunnel wall of the present invention, on the left and right of the tunnel wall, the negative bending force due to the prestress is smaller than that of the upper and lower sides of the tunnel wall.
Since the total sum of the acting negative bending forces can be suppressed,
In addition to improving the strength of the tunnel wall, the wire is located in the groove in each segment and is visible from the inner surface of the tunnel wall, so that there is an excellent effect that it is advantageous for wire installation work and maintenance.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a tunnel wall according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a segment constituting the tunnel wall of FIG. 1;

FIG. 3 is an axial side view showing a segment constituting the tunnel wall of FIG. 1;

FIG. 4 is a circumferential side view showing a segment constituting the tunnel wall of FIG. 1;

FIG. 5 is a partially enlarged view showing a method of fixing segments of inner and outer locking holes in grooves.

FIG. 6 is a partially enlarged view showing another example of a method of fixing the segments of the inner peripheral locking hole and the outer peripheral locking hole in the grooves.

FIG. 7 is a schematic sectional view showing a problem of a conventional tunnel wall.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tunnel wall 2 Segment 3 Groove 4 Inner circumference locking rod 5 Outer circumference locking rod 21 segment 22 segment K PC steel wire

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E21D 11/08 E04G 21/12 104

Claims (1)

(57) [Claims] 1. A tunnel wall formed by arranging a plurality of segments in a length direction and a circumferential direction of a tunnel along an excavation surface in a tunnel formed by excavating underground, wherein each segment A groove extending in the circumferential direction of the tunnel is formed, and is arranged in the length direction of the tunnel across the inside of the groove and displaced in the inner and outer peripheral directions of the tunnel. An inner peripheral side locking rod and an outer peripheral side locking rod are provided, and each of these segments is arranged so that the groove is continuous in the circumferential direction to constitute one unit of a tunnel wall. The inner peripheral locking rod is locked by an inner peripheral locking rod or an outer peripheral locking rod, is annularly disposed in the groove of each segment, and is restrained by a tightened wire. To the left and right Tunnel wall, characterized in that is engaged with the outer peripheral side latching rod are.