JPH0749757B2 - Tunnel construction method using tunnel lining element - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tunnel construction method using a tunnel lining element, which is used, for example, when constructing a tunnel that crosses under a railway, a road, or the like. Is.

[Prior Art] As a method of constructing a tunnel that crosses under a railway or a road, instead of the conventional construction method that does not divide the lining body by in-place concrete, the sectional shape is rectangular The long concrete or steel tunnel lining element of the above is buried by being propelled to the ground orthogonally to the tunnel lining cross section and mortar injection into the joint space between the elements or the internal space of the steel element A method is known in which concrete is poured into the concrete, and PC steel materials inserted into the respective elements are connected by pulling and fixing them to each other, and then the earth and sand inside the element connection body are excavated and removed.

[Problems to be Solved by the Invention] In such a tunnel construction method, when a concrete element is used, the position of the insertion hole of the PC steel material (PC cable or the like) connecting the elements is accurately adjusted between the adjacent elements. It is more difficult to make them coincide with each other, and if the insertion holes are misaligned, it is difficult to deal with them because the local parts in the soil cannot be visually recognized. Therefore, if the diameter of the insertion hole is widened so that this PC steel material can be easily inserted, the positioning error of the PC steel material will increase, and at the same time, the mortar injected into the joint will leach into the other joint space and the mortar flow path beyond that. Then, the mortar cannot be injected thereafter.

When steel elements are used, the transmission of shearing force may be insufficient if the steel plates that define the boundaries between adjacent elements are flat. Need to be provided.

[Means for Solving the Problems] The present invention has been made to solve the above problems, and is made of a plurality of long concretes that are orthogonal to the lining cross section with respect to the ground where a tunnel is to be constructed. Tunnel lining elements and hollow steel tunnel lining elements that open to the concrete element side are alternately arranged and buried horizontally, and by inserting PC steel between each element, each element is By connecting each other to form an element connection body, then concrete is poured into the steel element, and when the required strength is reached, the PC steel material is tension-fixed to introduce a compressive force into the concrete of each element. After completing the element connection body as prestressed concrete, excavation and removal of earth and sand inside the element connection body It is characterized in Rukoto.

[Operation] According to the method for constructing a tunnel by the tunnel lining element of the present invention, a worker enters the steel elements on both sides of one concrete element, and the PC steel material is inserted into all the concrete elements. Since the work can be performed, it is possible to easily and surely carry out the work of routing the PC steel element to the element connection body, and it is possible to take a measure to prevent the concrete from flowing into the insertion hole of the PC steel material.
In addition, the strength of the structure is improved by molding concrete elements that are easy to manufacture in complicated shapes into shapes that transmit shearing force to concrete placed in steel segments. Is planned.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a tunnel constructed in the ground based on the present invention. This tunnel 1 has a plurality of long concrete elements 2 which are orthogonal to the lining cross section with respect to the ground G, and hollow. -Shaped steel base element 3, corner element 4, and main element 5 are alternately arranged and horizontally propelled to be embedded, and a PC cable 6 (PC steel material) is inserted between each element 2, 3, 4, and 5. Then, both ends thereof are fixed to the base element 3, and the space such as joints between the steel elements 3, 4, 5 and the joints 2, 3, 4, 5 made of steel is filled with concrete to ensure that the concrete is sufficiently filled. After hardening, the PC cable 6 is tensioned to integrate the elements 2, 3, 4, 5 into the element connecting body 7, and then the earth and sand inside the element connecting body 7 are excavated and removed. It has been built.

The PC cable 6 is bent around the element connecting body 7 along a portion where a tensile force acts so as to resist the surrounding earth pressure.

In the element connecting body 7, the base element 3 is attached to the lowermost leg of the vertical portions 8 on both sides,
The corner element 4 made of steel is embedded in the corner where the vertical part 8 and the horizontal part 9 intersect, and further, the element 2 made of concrete and the main part made of steel are provided between the vertical part 8 and the horizontal part 9. The elements 5 are alternately arranged and buried.

The concrete element 2 has a substantially rectangular cross section,
A shear key 10 extending in the longitudinal direction is formed on the surface on the short side. The shear key 10 is a groove for transmitting a shearing force to concrete when the concrete is placed in the steel elements 3, 4 and 5 later.

The element 2 has a groove-shaped shear key 10 formed on the surface on the short side and a large number of PC cable insertion holes 11 provided at intervals in the longitudinal direction. Further, a reinforcing hole 12 for inserting a PC cable (or a steel rod, a reinforcing bar, etc.) for reinforcement and connection may be provided between the end faces in the longitudinal direction.

In addition, in the case of this concrete element 2, in order to reduce the weight and to effectively act the stress caused by the PC cable,
As shown in the figure, it is preferable that the meat is removed at appropriate intervals and the foamable filler 13 is filled therein.

As shown in FIG. 4, the steel base element 3 has a substantially convex cross section, is covered with steel plates 14 on both sides, is connected by a truss reinforcement 15 at its upper portion, and is open downward. Further, as shown in FIG. 5, a projecting portion 16 projecting forward is formed at the center at the tip end in the propulsion direction, and a step portion 17 is provided which is displaced forward and backward. By forming such a tip shape, when propelling to the ground, the stress in the ground is not concentrated at one location but dispersed, so that there is an advantage that face collapse can be prevented in advance.

As shown in FIG. 1, the corner element 4 made of steel is provided with a truss reinforcement 18 on the surface facing the vertical portion 8 and the horizontal portion 9 of the element connecting body 7, and the other surface is covered with the steel plate 19. It becomes.

As shown in FIG. 6, the steel main element 5 has a hollow shape in which a pair of steel plates 20 having a rectangular cross section and parallel to each other are connected by a truss reinforcing material 21. In this case, the steel plate 20 is on the long side of the cross section.

In addition, in each of the steel elements 3, 4, and 5 described above, the truss reinforcing members 15, 18, and 21 may have a lattice structure.

Now, subsequently, the procedure of the method for constructing the tunnel shown in FIG. 1 using the concrete element 2 and the steel elements 3, 4, and 5 will be described.

According to the gate-shaped arrangement shown in FIG. 1, the concrete element 2 and the steel elements 3, 4, 5 are arranged.
Are alternately arranged and propelled into the ground to be buried. At this time, in the element 2 made of concrete and the elements 3, 4, 5 made of steel, the surface on which the shear key 10 is formed and the surface on which the truss reinforcing members 15, 18, 21 are arranged face each other. Further, as shown in FIG. 7 (FIG. 7 exemplifies only the horizontal portion 9), the concrete element 2 is replaced by the steel plate 20 (14, 19) of each steel element 3 (4, 5). Insert it in between.

In order to bury the concrete element 2, the replacement element made of steel is first urged and buried, and the element 2 is abutted against the rear end of the element 2 and pushed out to be removed and recovered. This replacement element is used again when burying another concrete element 2.

When propelling the steel elements 3, 4 and 5 above the ground G, in order to prevent the inflow of earth and sand from the side where the truss reinforcements 15, 18 and 21 are arranged, As shown in the figure (this figure illustrates the main element 5), a plurality of slide plates 22 are attached to the outside of the truss reinforcement member 21 (18, 21) so as to cover the truss reinforcement member 21 in advance. When the propulsion is finished and it is buried in the ground G, the slide plate 22 is sequentially fed in the propulsion direction and removed.

If the tunnel to be constructed is long, it becomes necessary to connect two or more elements, but in the case of each steel element 3, 4, 5, the liquid tightness is maintained by means such as welding. To connect.

In addition, when connecting the concrete element 2, as shown in FIG.
A convex portion 24 that fits into the concave portion 23 is formed on the other side, and the adhesive material P is applied to one connecting end face, and then the concave portion 23 and the convex portion 24 are fitted to each other, and the PC cable 25 is inserted into the reinforcing hole 12. (Or a steel rod, a reinforcing bar, etc.) is inserted and this PC cable 25 is pulled and fixed.

In addition to this, as shown in FIG. 10, joint fittings 26 previously embedded in the connection end portions are fastened with bolts 27 and nuts (not shown), or as shown in FIG. The scale pipe 28 embedded in the end portion of the reinforcing hole 12 of No. 2 is fitted into the concave portion 29 provided at the end portion of the reinforcing hole 12 of the other element 2 and the PC cable is inserted into both reinforcing holes 12.
There is a means for inserting the sealing material S around the one element 2 by inserting the element 25.

Next, a worker enters each of the steel elements 3, 4 and 5, and the PC cable 6 is passed through the PC cable insertion hole 11 of the adjacent upper concrete element 2 from one base element 3 to A worker inside the main element 5 receives the end of the PC cable 6 and a concrete element 2 above it.
The PC cable 6 is passed through the PC cable insertion hole 11 of the above, and the worker inside the corner element 1 receives the end thereof.

In this way, when the PC cable 6 is inserted from below over the vertical portion 8 on one side, subsequently, the PC cable 6 is similarly inserted into the elements 2 and 5 by the operator inside the main element 5 of the horizontal portion 9. Through the corner element 4 on the other side, and then the PC cable 6 on the other vertical portion 8.
Is inserted by a worker in the main element 5 to reach the base element 3. Then, concrete is filled and poured into the corner element 4 and the main element 5 made of steel.

Once the cast concrete reaches the required strength,
A worker who has entered the base element 3 at both ends of the PC cable 6 pulls the PC cable 6 and applies a compressive force to the elements 2, 4 and 5 through which the PC cable 6 is inserted to fix the PC cable 6.

As described above, the vertical portion 8 and the horizontal portion 9 are integrated in the state where the prestress is introduced by the PC cable 6.

As a means for inserting the PC cable 6 into the element 2 made of concrete, as shown in FIG. 12, a sheath 31 is previously inserted into the PC cable insertion hole 11 of the element 2, and each element 2, 3, 4, When the burial of 5 is over,
After entering the steel main element 5, the sheath 31 is pulled out, bridged over the main element 5, and made continuous with the PC cable insertion holes 11 of the adjacent elements 2. Then, the PC cable 30 is inserted through the sheath 31 in the main element 5 and the PC cable insertion hole 11 of the element 2 and pulled and fixed. Then, after this, cement paste or the like is injected into the PC cable insertion hole 11 and the sheath 31 to fix the PC cable 6.

As another means, as shown in FIG. 13, a rubber bush with a collar at the opening of the PC cable insertion hole 11 of the element 2.
32 is pushed in and installed, and PC is inserted through this rubber bush 32.
Pass the cable 6. In this means, when the PC cable 6 is further fixed with cement paste as described above, as shown in FIG. 14, one PC cable 6 is inserted through the communication hole 33 for communicating the PC cable insertion hole 11 formed in advance. The cement paste is spread over all the PC cable insertion holes 11 in the element 2.

As described above, when prestress is introduced into the vertical portion 8 and the horizontal portion 9 to connect and integrate the elements 2, 4 and 5, concrete is put into the base element 3 where the PC cable 6 is pulled. Construction is completed by placing and prestressing structure.

Then, the earth and sand inside the element connecting body 7 are excavated and removed to obtain the tunnel 1.

According to the tunnel construction method as described above, a worker enters the steel elements 3, 4 and 5 on both sides of one concrete element 2 and the PC cable for all concrete elements 2 is inserted. Since the insertion work of 6 can be visually performed, the work of routing the PC cable 6 to the element connecting body 7 can be performed easily and surely and the work time can be shortened. Further, shearing force is transmitted by the shear key 10 formed on the concrete element 2, and the strength of the structure is improved.
That is, the concrete element 2 which can be provided with the share key 10 and the steel elements 3, 4 and 5 which ensure the insertion work of the PC cable 30 are assembled alternately so that each of the concrete element and the steel element is inserted. The advantage of the element that has it is utilized.

Note that FIG. 15 shows a state in which a tunnel having a long horizontal portion 9 is constructed based on the present invention. In this case, a vertical portion 8 is newly embedded in the middle and one PC cable 6 has a corner portion. There is a risk that the tension will decrease at the sharp bend and the coercive force may become insufficient, so the horizontal portion 9 and the vertical portion 8
One PC cable 6 is inserted in each. Further, a steel auxiliary element 40 is connected to the side of the corner element 4, and the end of the PC cable 6 of the horizontal portion 9 is fixed to the auxiliary element 40 as shown in FIG. The upper end of the PC cable 6 of the portion 8 is fixed to a locking piece 41 provided in the corner element 4.

[Effects of the Invention] As described above, according to the method for constructing a tunnel by the tunnel lining element of the present invention, a plurality of long strips are formed on the ground on which the tunnel is to be constructed so as to be orthogonal to the lining section. Concrete tunnel lining elements and hollow steel tunnel lining elements that are open to this concrete element side are alternately arranged and horizontally embedded, and by inserting a PC steel material between each element, Element is connected to each other to form an element connection body, then concrete is placed in the steel element, and when the required strength is reached, the PC steel material is tension-fixed to introduce a compressive force into the concrete of each element. After completing the element connection body as prestressed concrete, It characterized in that the sediment excavation and removal,
Since workers can enter the steel elements on both sides of one concrete element to insert the PC steel material into all concrete elements,
It is possible to easily and reliably carry out the work of connecting the PC steel material to the element connection body, and to take measures to prevent the concrete from flowing into the PC steel material insertion hole. In addition, the strength of the structure is improved by molding concrete elements that are easy to manufacture in complicated shapes into shapes that transmit shearing force to concrete placed in steel segments. The effect is also achieved.

[Brief description of drawings]

1 to 14 are views for explaining one embodiment of the present invention, FIG. 1 is a front view of a tunnel constructed according to one embodiment, FIG. 2 is a perspective view of a concrete element, 3 is a side view thereof, FIG. 4 is a perspective view of a base element, FIG. 5 is a top view of the tip thereof, FIG. 6 is a perspective view of a main element, FIG. 7 is an enlarged front view of a horizontal portion, and FIG. Is a perspective view illustrating a propulsion method of the main element,
The figure is a side view showing the connecting means of the concrete element, FIG. 10 is a perspective view of another connecting means, FIG. 11 is a side view of yet another connecting means, and FIG. 12 is a front view showing a PC cable insertion means. Sectional view, FIG. 13 is a frontal sectional view showing another insertion means, FIG. 14 is a plan sectional view of means for fixing a PC cable with cement paste, and FIG. 15 is a frontal view of a tunnel of another embodiment. Figure 16 is an enlarged view of the main parts. 1 ... Tunnel, 2 ... Concrete element, 3
…… Base element (steel element), 4…
… Corner element (steel element), 5 …… main element (steel element), 6 …… PC cable (PC steel material), 7 …… element connection, G …… ground.

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Claims (1)

[Claims] 1. A plurality of elongated concrete tunnel lining elements, which are orthogonal to the lining cross section, and a hollow steel tunnel which opens to the concrete element side, with respect to the ground on which the tunnel is to be constructed. The lining elements and the lining elements are alternately arranged and embedded horizontally, and the PC is placed between each element.
By inserting a steel material, each element is connected to each other to form an element connection body, then concrete is placed in the steel element, and when the required strength is reached, the PC steel material is tension-fixed, thereby Construction of a tunnel with an element for tunnel lining, characterized by excavating and removing earth and sand inside the element connection body after introducing a compressive force into the concrete of the element to complete the element connection body as prestressed concrete Method.