JPH0393999A - Tunnel covering construction method - Google Patents

Abstract

PURPOSE:To reduce the amount of excavation mud by contracting right and left arched half section type covering plates by means of connecting rods, within an excavated tunnel, and conveying the covering plates being contracted to a predetermined position, and then expanding the connecting rods to set the covering plates in their normal opposed, spaced relation, and installing the plates on the bottom of the tunnel. CONSTITUTION:Rails 2 are laid in an excavated tunnel 1 and a pair of right and left arched half section type precast concrete covering plates 3, 3 are conveyed into the tunnel. The covering plates 3, 3 are combined in an arched half section formation and are connected together at their top end portions 3b by a pair of right and left connecting rods 8, so that the pair of plates are in their contracted state in which they are in an opposed, narrowly spaced relation to each other. Under this state the pair if covering plates 3 are placed on a travelling truck 10 and conveyed to a predetermined position. Then The pair of covering plates 3 are lifted by a forklift 9 and they are adjusted and set in their normal opposed, spaced relation to each other by expansion of the connecting rods 8, and placed on the bottom of the tunnel. Thus drilling work of the tunnel section is reduced and so the cost for construction is reduced while the construction period is shortened.

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention is mainly applicable to hydroelectric power generation, sewerage, etc.
This invention relates to a lining method for small-scale tunnels such as waterway tunnels, particularly in self-supporting ground, in which a tunnel is excavated and its interior is lined with a precast concrete lining board.

``Prior art, problems to be solved by invention'' The conventional method of constructing a waterway tunnel is to excavate the ground after constructing earth retaining, and then lay chestnut stone at the bottom.
Is there an open-cut construction method in which precast concrete arch culverts integrated into a link shape are suspended from the bottom and connected in sequence, and the top is backfilled with earth and sand? If the ground is self-supporting, an integral arch-shaped precast concrete arch heart is carried inside the tunnel after excavation, and the lower end of the side wall is integrated with the cast-in-place concrete bottom concrete. Joined to ground 1
The PC lining method, which backfills fJJ gaps, is being implemented.

However, in the conventional PCI construction method, the arch culvert or integral arch type is used, so in order to transport it smoothly within the excavated tunnel, which is not uniform over the excavation cross section or the entire length, it is necessary to move the tunnel cross section outside the arch culvert. It has to be made larger than necessary (about 500 sm) than the diameter dimension, which increases the excavation work and the number of excavators, and also increases the ground gap, which requires more backfilling material and increases construction costs. There was a problem.

"Means for Solving the Problems" In order to solve the above-mentioned conventional problems, the present invention provides a half-section type precast concrete arch made of a pair of left and right arches with rails laid at the bottom of the excavated tunnel and a joint provided at the joint end of the top. The lining plates are connected by a flexible connecting member on the inside of the top joint ends of each other, and a connecting rod that is extendable and retractable is connected between the lower parts of the left and right lining plates using a telescopic jack, and this connecting rod is contracted. Using a forklift, lift the left and right lining plates with a narrower distance between them, place them on a trolley that runs on the rails laid at the bottom of the excavated tunnel, and move the trolley using a forklift. After transporting the excavated tunnel to the specified position, lift the left and right lining plates using fork software, extend the connecting rods, set the regular spacing, and install them on the bottom. We propose a construction method in which the panels are installed on the bottom and connected to each other, then integrated into the concrete base plate made of cast-in-place concrete, and then embedded in the gaps in the ground.

"Operation" The left and right arch half-section precast concrete lining plates are placed at the bottom of the excavated tunnel in a contracted state by contracting the connecting rod that expands and contracts using a telescopic jack to narrow the distance between the left and right lining plates. In order to load the material onto a trolley that runs on the laid rails and move the vehicle as it is to transport it to the designated position in the excavated tunnel, the cross section of the tunnel is excavated to the minimum necessary size without making it larger than necessary as in the past. This enables smooth conveyance of the lining board.

In addition, after the contracted lining board is transported to the required position, the connecting rods are expanded and installed on the bottom with the hills set at the regular spacing, so the integrated arch is connected by a joint at the joint end of the top. It becomes possible to assemble and install the mold lining board extremely easily.

Furthermore, since the lining plates can be raised and lowered and transported using a commercially available forklift, construction equipment is simple and equipment costs are low. "Embodiments" Below, embodiments of the present invention shown in the drawings will be described.
A rail 2 is laid at the bottom of the excavated tunnel 1, and a pair of left and right arched half-section precast concrete lining plates 33 are carried into the excavated tunnel.

The lining plate 3 is formed into an arch half-section shape from a side wall portion 3a and a semi-arched top portion 3b, and pin joints 4, 4' such as knuckle joints are provided at the joint end of the top portion 3b. Further, inserts 5 are buried in the front and back of the lower part of the side wall portion 3a.

The transported lining plates 3.3 are placed facing each other with the joining ends of the top end 3b of phase D touching, and are connected by a bendable connecting member 6 such as a hinge between the joining ends. At the same time, a pair of left and right connecting rods 8, which are extendable and retractable, are connected to the lower insert 55 by a central turnbuckle and a telescopic jack 7 such as a hydraulic jack, and the connecting rods 8 are contracted to narrow the mutual spacing. It is in a compressed state (contracted state). Then, in this contracted state, the opposing lining plates 3.3 are hooked to the connecting rods 8, 8 by the lift 7'' of the forklift 9, and lifted up. It is loaded onto the traveling truck 10, 10, or the traveling truck 10.10 is moved by the forklift 9 and transported to the lining part of the excavated tunnel 1.

After being transported to the construction department, the lining board 3 is removed by forklift 9.
, 3 at one end, move the traveling trolley 10 and 10 toward you, and expand the connecting rod 8 using the telescopic jack 7 to adjust and set the regular spacing so that the ground gap is maintained at about 100 mm. , hang this and install it on the bottom.

For this installation, screw the height adjustment bolt 12 into the insert 11 buried in the lower end surface of the side wall 3b of the lining plates 3, 3, and place the groove-shaped support plate l3 attached to the lower end on the rail 2. To support.

In this way, each pair of lining plates 33 are conveyed one after another in the same manner, and each pair is installed on the bottom, and the fittings 14 and 14 provided on the front and rear joint end faces are fastened together with bolts to continuously integrate the required span. .

Next, a bottom plate concrete 15 is poured using cast-in-place concrete, and the lower end of the side wall 3b of the lining plate 3.3 is integrated with this, and a back plate is also placed in the ground gap (about 100 mm) in the back. Inject the filling material 16.

The above construction is repeated for each required span to complete the construction.

"Effects of the Invention" As described above, according to the present invention, the left and right arch half-section precast concrete lining plates are connected by an end connecting member with their mutual top joint ends touching, and connected between the lower parts of each other. The connecting rod is contracted using a telescopic jack to narrow the gap between the left and right lining plates, and in the contracted state, it is loaded onto a traveling trolley that runs on the rails laid at the bottom of the excavated tunnel, and the traveling trolley is moved as it is. Since the lining plate is transported to a predetermined position in the excavated tunnel, it is possible to smoothly transport the lining plate in the tunnel cross section that has been excavated to the minimum necessary size without making it unnecessarily large as in conventional methods. In addition to reducing the amount, the amount of backing material can also be reduced because the gaps in the ground are also reduced, making it possible to reduce construction costs and construction periods.

In addition, after connecting the top joint ends with the end connecting material and transporting the contracted cover plate to the desired position, expand the connecting rods and set the regular spacing, and then attach the top plate to the bottom. Therefore, it is possible to extremely easily assemble and install integral arch-shaped lining plates connected by joints at the joint ends of the top ends.

Furthermore, since the lining plate can be raised and lowered and transported using a commercially available forklift, construction equipment is simple and equipment costs are low, making it economical.

[Brief explanation of drawings]

Fig. 1 is a side view showing an embodiment of the present invention, Fig. 2 is a front view thereof, Fig. 3 is a partial longitudinal sectional front view showing the construction state of the lower part of the lining board, and Fig. 4 is the completed state of the construction. FIG. l...Drilling tunnel, 2...Rail, 3...Lining plate, 3a...Top end, 3b...Side wall part, 6, 8, 9゜11 l3 l5 4,4' ・Joint...5・Insert, ・Connecting material,
7. Telescopic shack, ・Connecting rod, 9. Forklift, ・Fork, 1
0...Traveling trolley,...insert, 12...height adjustment bolt...support plate,
l4...Joint hardware,...bottom plate concrete, l6...backfilling material.

Claims (1)

[Claims] 1) A rail is laid at the bottom of the excavated tunnel, and a pair of left and right arch half-section type precast concrete lining plates with joints provided at the top joint ends are placed in contact with each other's top joint ends using end connecting materials. At the same time, a connecting rod that is extendable and retractable by a telescopic jack is connected between the lower parts of the left and right lining plates, and the connecting rod is contracted to narrow the distance between the left and right lining plates, and the forklift is moved. The vehicle is then lifted up by the forklift and loaded onto a traveling trolley running on the rails, and then the forklift is used to move the traveling vehicle to a predetermined position in the excavated tunnel.The forklift lifts the left and right lining plates, and the connecting rod is After expanding and setting it to the regular installation spacing, it is installed on the bottom, and the lining plates are installed on the bottom in the same way and connected to each other, and then integrated with the bottom plate concrete made of cast-in-place concrete, and then installed on the bottom. A tunnel lining method characterized by lining into mountain gaps.