JP2000141332A - Method and apparatus for manufacture of liner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a dense product, the dimensional accuracies of all the six surfaces of a liner of which are high, by a method wherein the action of a centrifugal force is effectively utilized by a simple device without employing a centrifugal molding drum. SOLUTION: This apparatus is equipped with a disc 31, which rotates at high speed in a horizontal plane, a plurality of engaging parts 16 provided center-axisymmetrically on the top surface of the disc 31 and an engaging fitment. Further, this apparatus employs a device equipped with the form 10 of a circular arcuate plate-like concrete tunnel liner, the outer surface of which is set to face upwards and on the central top surface of which, a concrete feed port 17 is equipped and the six surfaces of which are enclosed, and a concrete feeding device 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a circular-plate-shaped concrete tunnel liner by centrifugal molding.

[0002]

2. Description of the Related Art When manufacturing an arc-plate-shaped concrete tunnel liner, there is conventionally a technique of pouring concrete while applying a strong vibration to a form by a vibrator using a fixed form with an open top. In addition, there is a technology in which a mold is mounted in a cylindrical drum and the drum is rotated at a high speed to form a centrifugal force.

In the former method, concrete is poured into a formwork and compacted with an intense vibrator, and is poured while using a temporary upper lid to prevent the concrete from overflowing from the upper surface. Wait for the concrete to settle, remove the temporary top cover, iron the top, and then cure. In such a manufacturing method, the working time is enormous, the noise is intense, the dimensional accuracy of the outer surface of the liner is insufficient, and it is hard to fill every corner due to the hardened concrete, and the shortage of paste and the occurrence of junkers are caused. In addition, there is a problem in that the periphery of the aggregate is poor and chipping of the corner occurs.

On the other hand, in the technology of centrifugally forming an arc-plate-shaped concrete liner using a cylindrical drum, concrete with an extremely dense outer peripheral surface of the liner can be obtained. There has been a problem that the shape of the groove is not formed with high precision, and that "water droplets" occur on the end face. Japanese Patent No. 2667363 discloses a technique for improving this. In this technology, a separate formwork to be attached to a cylindrical drum type centrifugal molding machine is prepared, concrete is poured using another device to form the end face of the concrete liner first, and then this formwork is centrifugally molded. Since it is mounted on a machine and centrifugally molded, it is possible to produce an excellent product without defects, but there is a problem that the production process is complicated and time-consuming.

[0005]

According to the former technique,
In recent years, workable high-fluidity concrete has been developed, and the problem of the conventional noise has been solved. People are hanging on. It should be noted that high-fluid concrete is expensive and difficult to manage because it uses a large amount of powder such as cement, a thickener, and a high-flow agent, and has a problem that it is not suitable for general use.

In the latter technique, a large-scale centrifugal forming drum requires a large-scale apparatus to rotate at a high speed.
As described above, there is a problem that it takes time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel technique that solves the above-mentioned conventional problems, and effectively utilizes the effect of centrifugal force with a simple device without using a centrifugal forming drum. The present invention provides a technique for obtaining a solid product with high dimensional accuracy of the six sides of the liner.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In manufacturing an arcuate plate-shaped concrete tunnel liner, a six-sided formwork having only a concrete supply port opened is provided with an outer peripheral surface of the liner. It is an object of the present invention to provide a method for manufacturing a liner, wherein concrete is supplied from above the center of a formwork to form a liner while being rotated at a high speed in a horizontal plane as an upper surface.

[0009] In the present invention, by rotating the form in a horizontal plane, a horizontal centrifugal force is applied to the concrete so that the concrete can be surely filled to every corner of the liner. Is densely filled, and a good product without corner chipping or the like can be obtained.

Since the outer peripheral surface of the arc-shaped plate-shaped liner is directed upward, the center of the formwork is highest, and light air or moisture in the concrete is squeezed out by centrifugal force due to horizontal rotation. No air bubbles remain on the concrete surface after exiting the formwork. Therefore, there is no need for post-finishing. In addition, since the concrete input operation is performed during the rotation of the formwork, a stable product with no loss in the operation can be obtained.

The outer surface of the product has a high dimensional accuracy because all six surfaces are formwork surfaces, and the surface of the product is smooth, and a good seal can be obtained without damaging the tail seal of the shield machine even in a tunnel construction. .

The apparatus of the present invention which can preferably carry out the method of the present invention comprises: (a) a disk rotating at a high speed in a horizontal plane; and (b) a plurality of locking members provided on the upper surface of the disk symmetrically with respect to the central axis. (C) a formwork having a concrete supply port in the center of the outer surface plate with a lower surface provided with a locking tool for locking to these locking portions, and (d) a concrete supply device. This is a liner manufacturing apparatus.

[0013] The centrifugal force should be large enough that the concrete does not separate. Therefore, the manufacturing apparatus of the present invention does not require excessive investment, and the mold can be inexpensive without damaging the mold. In addition, a good working environment with less noise is obtained. Further, a high quality concrete tunnel liner having a denser and more accurate shape on both sides can be labor-savingly obtained by using ordinary concrete.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 8 shows a concrete liner 60 for one circumference in which an arc plate-shaped concrete tunnel liner 50 is assembled.
FIG. FIG. 7 shows an arc-plate-shaped concrete tunnel liner 50 constituting the tunnel liner 60. In the conventional method, as shown in FIG. 7, the form is placed on the vibrating table and concrete is poured with the outer peripheral surface 51 of the liner facing upward, so that the outer peripheral surface 51 of the product liner is a hand finished surface. Many irregularities or bubbles were generated.
Although the inner peripheral surface 52 of the liner has an excellent finished surface, it is inevitable that defects occur in the ring side surface 54, the end surface 53, and the grout hole 55.

FIG. 1 is a front sectional view of a mold 10 according to an embodiment of the present invention, and FIG. 2 is a side sectional view thereof.

A concrete inlet 17 is attached to the upper center of the formwork 10, and a grout hole forming pipe 21 is attached to the center thereof. Grout hole forming pipe 21
The grout hole cover 22 is put on the bottom plate 11 with cover bolts 23 so that concrete does not get on the top of the bottom plate 11.
Wife frame side plates 12, 12 are attached to both wives of the bottom plate 11. Also, as a locking member 16 which locks to a locking portion 34 provided on the rotating disk 31 on the frame 15 attached below the bottom plate 11, four form-fixing guides are provided. The ring side frame side plates 13 and 13 are also attached to the bottom plate 11.
The locking portion 34 and the locking tool 16 are not limited to the conical fitting type of this embodiment, but may have other shapes and types. The main point is that the engagement type should be easy to engage and disengage, easy to align, and not disengaged by high-speed rotation.

The method of using the embodiment device is as follows.
With the top plate 14 of the mold 10 removed, a predetermined reinforcing cage (not shown) is mounted in the mold 10 and then the top plate 14 is attached. In this formwork, all six surfaces are formwork surfaces, and the dimensional accuracy of the product is improved without one surface being released as in the past. This mold 10 is placed on a rotating disk 31 as shown in FIGS. The rotating disk 31 is provided with an engaging portion 34 having a taper so as to prevent the mold from being misaligned during rotation and to facilitate alignment, and is engaged with the bottom surface of the mold 10. Since the locking portion 16 is provided, the mold 10 is easily mounted on the rotation center of the rotating disk 31. As shown in FIG. 4, the rotating disk 31 has a receiving base 37 and a central spherical seat shaft 35 at the center, and has a driving shaft 36 connected to a roller 32 and a motor 33 on the peripheral surface of the rotating disk 31.
This structure may be such that the center shaft 38 is driven by the motor 33 as shown in FIG.

Next, the hopper 4 of the concrete loading device 40
1 is inserted into the concrete inlet 17 of the formwork. The concrete loading device 40 is supported on a support 42 so as not to cooperate with the rotation of the formwork 10. Concrete is poured into the hopper 41 while rotating the rotating disk 31 (the mold is also rotating). Concrete is grout hole cover 22 and hopper 41
When it flows from the throat portion 43 of the gap and reaches the bottom plate 11, the mold 10 is sequentially clogged from the four corners by the centrifugal force.

The air extruded by driving the concrete is expelled from the gap between the inlet 17 and the outer surface of the hopper 41. At this time, air and water in the concrete are simultaneously squeezed out. That is, centrifugal compaction is performed simultaneously with the charging operation. After pouring a predetermined amount of concrete, the rotation of the rotating disk 31 is stopped, the concrete charging device 40 is removed, and a charging port cover 45 is attached as shown in FIG. The liner forming operation is completed.

In order to improve the quality of the concrete surface in the vicinity of the charging port 17, 0.1 to 1% of the concrete volume of concrete is further charged into the charging port 17 before the charging port lid 45 is attached. By tightening, there is also a pressing effect, and the finished surface of the liner becomes good.

As described above, the inner peripheral surface 5 as shown in FIG.
2. The tunnel liner 50 without bubbles and defects can be formed on both the ring side surfaces 54 and the both end surfaces 53.
In the product liner, small finger-sized bubbles are scattered in the vicinity of the inlet 17; however, there is no problem in performance, and the repair time is very small.

As the concrete, a concrete having a flow of 45 to 55 cm of a so-called middle fluid concrete among concrete flows of 35 to 75 cm is used.
The operation is completed when such concrete is poured with a centrifugal force of 2 to 12 g (g is the acceleration of gravity) and a charging time of 2 to 20 minutes. Very good results are obtained with a centrifugal force of 3 g to 6 g and a charging time of 5 minutes to 15 minutes. In the case of harder concrete, as shown in FIG.
It is preferable that the rotating blades 46 be detachably attached to the rotating blades. The rotating blades 46 form a slope and rotate to push the concrete downward.

As described above, since the medium fluid concrete or ordinary concrete is mainly used as the concrete, the increment of the concrete unit price is small. The apparatus of the present invention has relatively simple equipment and a simple formwork as compared with the apparatus using a vibrator, and the formwork is less damaged.

[0025]

According to the present invention, it is possible to easily obtain a dense circular plate-shaped concrete tunnel liner having high surface finishing accuracy on all six surfaces by centrifugal molding using a simple apparatus. This method can use medium fluid or ordinary concrete, and can produce high-precision products at a lower cost than conventional vibrator-type production methods. In addition, the time required to obtain the product can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional front view of the device of the present invention.

FIG. 2 is a partial side view of the device of the present invention.

FIG. 3 is a partial side view of the device of the present invention.

FIG. 4 is a perspective view of a rotating disk of the device of the present invention.

FIG. 5 is a perspective view of a rotating disk of the device of the present invention.

FIG. 6 is a partial sectional view of a mold.

FIG. 7 is a perspective view of a concrete tunnel liner.

FIG. 8 is a perspective view showing the assembly of the concrete tunnel liner for one circumference.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Form frame 11 Bottom plate 12 Wife frame side plate 13 Ring side frame side plate 14 Top plate 15 Frame 16 Locking part (Form fixing guide metal fittings) 17 Input port 21 Grout hole forming pipe 22 Grout hole cover 23 Stop bolt 30 Rotating device 31 Disk 32 Receiving roller 33 Drive motor 34 Engaging part 35 Receiving part 36 Drive shaft 37 Base 38 Rotating shaft 40 Concrete dosing device 41 Hopper 42 Receiving beam 43 Throat part 45 Cover 46 Rotating blade 50 Concrete liner 51 Outer peripheral surface 52 Inner peripheral surface 53 Wife surface 54 Ring side surface 55 Grout hole 60 Concrete liner for one circumference assembled

Claims (2)

[Claims] In producing an arc-plate-shaped concrete tunnel liner, a concrete hexagonal form having only a concrete supply port is rotated at a high speed in a horizontal plane with an outer peripheral surface of the liner as an upper surface, and concrete is formed from above the center of the form. And forming a liner. 2. An apparatus for manufacturing an arc-plate-shaped concrete tunnel liner, comprising: a disk rotating at high speed in a horizontal plane; and a plurality of locking portions provided on the upper surface of the disk symmetrically with respect to a central axis.
An apparatus for manufacturing a liner, comprising: a formwork having a concrete supply port in the center of an outer surface plate, and a concrete supply device;