JPH07107356B2 - Tunnel lining structure - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a tunnel lining having a multiple circular cross section in which a plurality of circular arcs are sequentially connected.

(Prior Art) Conventionally, a tunnel having a multi-section circular cross-sectional shape formed by connecting a part of two circles having the same diameter, that is, two arcs, has been constructed and used for roads, iron roads, etc. .

The wall surface of the tunnel having the multiple circular cross section is defined by a plurality of segments like the wall surface of the tunnel having the circular cross section. Further, in this tunnel, a pillar is arranged between a pair of upper and lower lining segments located at the upper and lower intersections of the two circles, that is, the connecting points of the two arcs, and the pillar urges the tunnel lining by the earth pressure. It is supported so as not to be crushed.

(Problems to be Solved by the Invention) By the way, the pillar also functions as a partition member of the tunnel space, and limits the use and usage of the tunnel space. For example, when each space partitioned by the pillars is used for an iron road, the pillars obstruct the construction of the crossover.
Further, the pillars give a feeling of psychological pressure to a person passing by a train or a car in each space.

It is an object of the present invention to eliminate the cause that hinders the effective use of the space of a tunnel having a multi-section circular cross-sectional shape.

(Means for Solving the Problem, Action and Effect of the Invention) The present invention relates to a structure of a tunnel lining having a cross-sectional shape of a multiple circle formed by sequentially connecting a plurality of arcs, and the multiple circle is provided. A plurality of lining segments, and a pair of upper and lower tension members that connect two pairs of lining segments that define part of the arcs at both ends of the multiple circle to each other and exert a tensile force on both lining segments. including.

According to the present invention, both sides of the tunnel lining receive a tensile force toward each other via each tensioning member, and due to the action of this tensile force, the tunnel lining is crushed by earth pressure. Without losing its shape. Further, the tension members are located above and below the tunnel space, and do not partition the tunnel space between both sides of the lining. As a result, the tunnel space can be used with a greater degree of freedom than the conventional one, and the tensioning member can significantly give a feeling of psychological pressure to passersby in the tunnel space as compared with the conventional one. Reduce.

Each tensioning member may be arranged to abut the lining segment at each intersection of two arcs. The movement of the lining segment due to the soil water pressure can be further suppressed by the contact of the lining segment with each tension member.

It is desirable that the pair of upper and lower tension members be arranged in parallel with each other.

(Embodiment) Referring to FIG. 1, a tunnel lining having a double circular cross sectional shape in which two arcs having the same diameter are sequentially connected.
10 is shown.

The tunnel lining 10 defines a plurality of lining segments 12 defining the double circle and two arcs at both ends of the double circle, that is, two arcs 14 and 16 defining the double circle. And a pair of upper and lower tensioning members (18, 20) respectively connecting the pair of lining segments (12) and exerting a tensile force on each pair of the lining segments.

The tunnel having the double circular cross-sectional shape is formed by excavating one tunnel having a circular cross section with one shield excavator, and then by a similar shield excavator, in parallel with the tunnel and the wall surface of the tunnel. It is constructed by excavating the natural ground that defines a part of, while forming one tunnel with another circular cross section. By this method, a tunnel having a circular cross-sectional shape of three or more stations is constructed. The double circular cross-section tunnel is also constructed using a single shield machine having double cutter faces and a shield body.

During the tunnel excavation, as in the construction of a tunnel with a single circular cross section, a plurality of lining segments 12 are arranged along the excavation surface of the tunnel, the lining segments 12 being Fasteners such as bolts and nuts (not shown) axially and circumferentially
Are connected to each other.

Each tensioning member 18, 20 shown in FIG. 1 is made of PC rope, and each end of each tensioning member has a lining segment 12 with suitable means.
It is fixed to.

Referring to FIG. 2, the upper tension member 18 is constructed as described above.
The segment 12 to which the end of the PC steel wire is fixed is preliminarily embedded with a "V" -shaped sheath 22 into which the end of the PC steel wire can be inserted, and the end of the PC steel wire extending through the sheath 22. A step 26 is provided in advance so that a locking member 24 attached to the section can come into contact therewith. The sheath and the step for the PC steel wire constituting the lower tension member 20 are provided symmetrically with respect to a line parallel to the PC steel wire 18 as seen in FIG.

The pair of upper and lower PC steel wires, after assembling a plurality of lining segments 12 extending in the circumferential direction of the tunnel, that is, a plurality of lining segments of one winding, preferably the axial direction of the tunnel of the plurality of lining segments of one winding. It is fixed to the two pairs of lining segments 12 in the central part of and is respectively tensioned with a size that takes into consideration the size of soil water pressure in the ground constructed of the tunnel. As a result, the pair of lining segments 12 forming a pair in each wrapping segment for constructing the tunnel lining receives a tensile force toward the other one, and the wrapping segments of the one roll are provided. The mutual matching in is strengthened. As a result, the tunnel lining 10 withstands the earth pressure and maintains its cross-sectional shape.

Further, as shown in FIG. 3, each tension member can be a reinforced concrete plate having a width dimension smaller than the width dimension (length in the axial direction of the tunnel) of the lining segment 12.

The lining segment 12 to which the end of the reinforced concrete plate is fixed is provided with a recess 28 that can accept the end of the reinforced concrete plate in advance, and also penetrates the end received in the recess 28. A threaded socket 32 is embedded that is capable of receiving and threading the shank of the extending bolt 30. The concave portion and the socket for fixing the end portion of the reinforced concrete plate constituting the lower tension member 20 are preliminarily provided in the other lining segment in line symmetry as in the example shown in FIG.

The reinforced concrete plate has both lining segments 12
Then, the soil pressure exerted on the wrapping segments 12 of one winding causes the tensile force to be applied to the lining segments 12 so that the tensing of the lining segments 12 is relatively prevented from being deformed.

Each tension member may be made of steel bar, shaped steel, or the like, instead of the illustrated example. Each tension member is composed of a pair of reinforced concrete plates or a pair of shaped steels whose one ends face each other, and bolts and nuts attached to these one ends for connecting both the reinforced concrete plates or both shaped steels. can do. According to this, after fixing the other end of both reinforced concrete plates or both shaped steels to the lining segment 12, by performing the operation of screwing the bolt into the nut, the two reinforced concrete plates or both shaped steels to each other Can be drawn towards one side.
As a result, both reinforced concrete plates or both steel sections are tensioned, and a tensile force is exerted on each pair of lining segments 12.

Further, it is desirable that the tension members 18 and 20 are arranged so as to contact the lining segment 12 at the two intersections a and b of the two arcs 14 and 16. According to this, both tension members 18,2
0 acts to prevent the vertical movement of both segments 12 at the two intersections a and b.

Instead of the illustrated example in which they are arranged horizontally and in parallel, both tensioning members 18, 20 can be arranged non-horizontally and non-parallel, as shown in phantom in FIG.

A pair of upper and lower tension members 18 and 20 respectively connecting two pairs of lining segments 12 defining a part of arcs 14 and 16 at both ends of the double circle and respectively exerting a tensile force on each pair of lining segments. Including and

Further, the present invention can be applied to a tunnel lining having another cross-sectional shape of multiple circles, an example of which is shown in FIG.

The illustrated tunnel lining 10 has a three-section circular cross-sectional shape in which four circular arcs are successively arranged, and two pairs of lining segments that define a part of the circular arcs 14 and 16 at both ends of the three circular circle. 12 are connected by tensioning members 18 and 20 made of a pair of upper and lower PC steel wires, respectively.

Further, in this example, instead of the example of FIG. 1 in which all of the multiple circular constituent arcs have the same radius, one of the multiple circular constituent arcs has a different radius from the other circular arcs. More specifically, the arcs 14 and 16 at both ends have a smaller and equal radius than the two arcs 34 between them.

Each tension member 18, 20 abuts the lining segment 12 at four intersections a, b, c, d of the arcs 14, 16 at both ends and the two arcs 34 between them. Of course, as described with reference to the example shown in FIG. 1, the tension members 18, 20 have four intersection points a,
b, c, d can be arranged so as not to be in contact with the lining segment 12, and from these intersections a, b, c, d towards the lining segment 12 defining the respective arcs 14, 16. The part of each tensioning member 18, 20 that extends can be set to form an angle with the other part between the intersections a and c and the other part between the intersections b and d. Similarly to the example shown in FIG. 1, the tension member may be made of a suitable material.

Furthermore, in addition to the tunnel lining of the example of FIG. 4 in which the centers of all arcs 14, 16, 34 are on one straight line,
The centers of the left and right circular arcs 14 and 16 are on a straight line, but the central circular arc 3
The center of 4 can be applied to tunnel linings that are not on this straight line.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a tunnel lining according to the present invention, FIGS. 2 and 3 are enlarged cross-sectional views of a fixing portion of an end portion of a tension member, and FIG. 4 is a cross-section of a tunnel lining of another example. It is a side view. 10: tunnel lining, 12 lining segment, 14, 16: arcs at both ends of multiple circles, 18, 20: tension member, 34: arc.

Claims (2)

[Claims] 1. A structure of a tunnel lining having a cross-sectional shape of a multiple circle formed by sequentially connecting a plurality of arcs, wherein a plurality of lining segments defining the multiple circle and the multiple circle. A structure of a tunnel lining, which includes a pair of upper and lower tension members that connect two pairs of lining segments that define a part of the arcs at both ends of each other and exert a tensile force on the both lining segments. 2. The tunnel lining structure of claim 1, wherein each tension member abuts the lining segment at each intersection of two arcs.