JP3433893B2 - Mouth stop device for small diameter propulsion - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel for burying communication pipes, sewers, gas pipes and the like underground.
The present invention relates to a small-diameter propulsion well stop device used for propulsion by a non-cutting method that does not cut the ground. [0002] In general, when this kind of standing pit construction, embed the sheet pile so as to surround the outer shape of the vertical shaft, subjected to ground improvement advance by chemical injection method,
Drill holes once after increasing the stability of the ground. Then, after confirming the condition of the ground improvement, an insertion hole for propelling the small-diameter propulsion wellhead was drilled in the sheet pile by gas fusing work, and the small-diameter propulsion wellhead water stop device was attached so as to surround this insertion hole. Can be FIG. 3 is an exploded perspective view showing a conventional small-diameter propulsion well stop device, which will be described with reference to FIG. In FIG. 1, reference numeral 20 denotes a sheet pile, in which a shaft 3 is built inside the sheet pile 20, and the outside is surrounded by an underground 2;
After the is constructed, a propulsion hole (not shown) for propelling the small-diameter propulsion wellhead is formed by gas welding. Reference numeral 21 denotes a steel box, one side of which is open, covers the above-described propulsion hole of the sheet pile 20 on the opening side, and is fixed so as to be in close contact with the sheet pile 20 by welding. A large-diameter insertion hole 22 is formed in the center of the other side surface of the box 21.
A large number of bolts 23 are implanted in the peripheral edge of the bolt 2. Reference numeral 25 denotes a water-stop packing, in which an insertion hole 26 having the same diameter as the insertion hole 22 of the above-mentioned box 21 is formed in the center, and a large number of small-diameter through holes 27 are formed in the periphery of the insertion hole 26. Are drilled. Reference numeral 29 denotes a steel holding plate, in which an insertion hole 30 having the same diameter as the insertion hole 22 of the box 21 is formed in the center, and a large number of small-diameter through holes 31 are formed in the periphery of the insertion hole 30. Have been. In such a configuration, the through hole 27 of the waterproof packing 25 is engaged with the bolt 23 of the box 21, the through hole 31 of the holding plate 29 is engaged with the bolt 23, and the nut 32 is screwed into the bolt 23. Thereby, the waterproof packing 25 is interposed between the box 21 and the holding plate 29. The box 21, the watertight packing 25, and the holding plate 29 thus assembled function as wellhead equipment, and a propulsion device (not shown) is inserted through the insertion hole 30 to tunnel into the underground 3, that is, a tunnel. This is to prevent inflow of sediment and groundwater when forming a small-diameter wellhead. [0005] In the above-described conventional water stop device for small-diameter propulsion, the wellhead device is attached to the wall of the shaft 3, that is, the box 21 is brought into close contact with the sheet pile 20. Since welding using fire is used for the mounting work, not only a long time is required for the work, but also a fire may occur. In addition, earth and sand and groundwater flowed out from the part where the underground 2 propulsion machine passed,
Since this may pass through the insertion hole 22 of the box 21 and flow into the shaft 3, it is necessary to inject the chemical at the same time. Therefore, during the period from the start of the injection of chemicals to the stabilization of the ground, the small-diameter propulsion work must be interrupted, which lengthens the construction period and increases costs due to the use of chemicals. Was. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a small-diameter propulsion well stop device which shortens the construction period and reduces costs. . [0007] [Means for Solving the Problems] To achieve this object, the wellhead water stop device for small-diameter propulsion according to the present invention, holes are drilled into the member in contact against the side wall of the standing pit, this Cover the hole with a pair of shielding members and packing provided between these shielding members,
The shielding member is formed of a material that can be broken by pressing of a propulsion device, and the packing is formed of a material having flexibility, and an engagement hole having an outer diameter smaller than the outer diameter of the propulsion device is formed in the packing. It was done. Therefore,
Before the propulsion operation is performed by the propulsion unit, the shielding member prevents the inflow of sediment and groundwater. After the shielding member is destroyed for the propulsion operation by the propulsion unit, the packing prevents the inflow of sediment and groundwater. . An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an enlarged sectional view showing a main part of a small-diameter propulsion well stop device according to the present invention, and FIG. 2 is a view for explaining an operation of forming a small-diameter propulsion well mouth.
In these figures, reference numeral 4 denotes an enclosing member for forming a manhole, which is formed in a rectangular shape with a bottom and made of concrete, and has a circular insertion hole 5 for inserting a propulsion device at a side portion. I have. A mounting plate 6 formed of a thin steel plate in a ring shape in a side view is fixed to a peripheral surface of the insertion hole 5 with an adhesive. On the inner peripheral surface of the mounting plate 6, four protruding pieces 7, 8, 8, 7 are erected in the width direction of the mounting plate 6 in a comb shape, and these four protruding pieces 7, 8, 8 are formed. , 7 are provided in plural sets at equal rotation angles in the circumferential direction, and through holes (not shown) for inserting bolts are formed in these protruding pieces 7, 8, 8, 7. Reference numeral 10 denotes a packing, which is formed of a flexible material, in this embodiment, a hard rubber, in a circular shape having an outer diameter slightly larger than the inner diameter of the mounting plate 6, and a propulsion device described later in the center. Outer diameter L smaller than 15 outer diameter L2
1 is formed.
A through hole (not shown) for inserting a bolt is formed in an outer peripheral portion of the packing 10 in correspondence with the above-mentioned protruding piece 8, and a bolt 11 is inserted into the through hole of the protruding piece 8 and the through hole of the packing 10.
The packing 10 is positioned at the center in the width direction of the mounting plate 6 and mounted. Reference numerals 13 and 14 denote shielding members which are formed in a circular shape whose outer diameter is slightly larger than the inner diameter of the mounting plate 6, and which have through holes for bolt insertion corresponding to the projecting pieces 7 on the outer peripheral portion. (Not shown) are drilled. These shielding members 13 and 14 are provided with through holes of the projecting piece 7 and the shielding members 13 and 14.
The bolts 11 are inserted through the through holes 14 and the nuts 12 are screwed together, so that the packing 10 is interposed therebetween so that the insertion holes 5 are closed at both ends in the width direction of the mounting plate 6. Can be These shielding members 13 and 14, when the embedded shroud 4 as described later on standing pit 3 is not destroyed by the pressure of the pressure and groundwater of sediment in the ground 2, and breakable by the pressing force of the propulsion unit 15 It is formed of a material having high strength, in this embodiment, urethane. Next, the operation of forming the small-diameter propulsion wellhead in the small-diameter propulsion wellhead water stop device having such a configuration will be described. First, we drilled standing anti 3 inner shape of slightly larger than the outer shape of the shroud 4 in the ground 2, the surrounding member 4 to the stand anti 3
Buried. At this time, the outer wall of the shroud 4 is in contact against the inner wall of the standing pit 3, the shielding member 14 is applied the pressure in the pressure and groundwater sediment ground 2, and has a strength to withstand this Therefore, the inflow of the earth and sand and the groundwater into the surrounding member 4 is prevented without being destroyed. In this state, as shown in FIG. 2 (a), the screw housing 16 of the propulsion unit 15 is inserted from the inside of the enclosure member 3 into the center of the insertion hole 5 of the enclosure member 3, ie,
It is positioned so as to correspond to the engagement hole 10a of the packing 10, and is operated by moving in the direction of arrow A in the figure. As shown in FIG. 2B, first, the screw housing portion 16 of the propulsion device 15 comes into contact with the inner shielding member 13.
Since the shielding member 13 is formed of a material that can be broken by the pressing of the propulsion unit 15, it is broken as shown by a broken line in the figure. Next, as shown in FIG.
5 is in contact with the packing 10.
Since the packing 10 is formed of a flexible material, the screw housing portion 16 passes through the engagement hole 10 a while elastically deforming the packing 10, and comes into contact with the outer shielding member 14. Further, when the propulsion device 15 is moved in the direction of arrow A, as shown in FIG.
Is destroyed as shown by a broken line in the figure, and thereafter, the propulsion unit 15 moves in the direction of arrow A to form a small-diameter propulsion wellbore in the underground 2. Before the shielding member 14 is broken, the inner diameter L1 of the engagement hole 10a of the packing 10 is reduced.
Is formed smaller than the outer diameter L2 of the propulsion device 15, so that the peripheral edge of the engagement hole 10a is in close contact with the outer peripheral portion of the propulsion device 15 while being elastically deformed. It is prevented from flowing into the member 4. This eliminates the need for chemicals that were conventionally used for ground stabilization, thereby reducing costs and shortening the construction period because there is no interruption in small-diameter propulsion work from the start of chemical injection until ground stabilization. You. Here, even when it is not necessary to form a small-diameter thrust wellbore by the propulsion device, the nut 12 is loosened so that either the packing 10 or the shielding members 13 and 14 can be detached from the insertion hole 5. can do.
Therefore, it is possible to use the enclosure member 4 for both the case where it is necessary to form the small-diameter propulsion wellbore by the propulsion device and the case where it is not necessary. The cost can be reduced by the effect. In the embodiment described above, when the propulsion device is moved from the inside of the enclosure member 3 to the underground 2,
In other words, the case where the propulsion device is moved from the inside of the earth and sand toward the side with the earth and sand is shown, but the water stopping effect is also obtained when the propulsion device is moved from the side with the earth and sand toward the inside without the earth and sand. Of course. For example, when a small-diameter propulsion wellhead is formed up to the adjacent enclosure member 4 by the propulsion device moving underground, the propulsion device 15 first destroys the outer shielding member 14 in contact with the underground 2. . At this time,
The inner shielding member 13 prevents the earth and sand in the ground 2 and the groundwater from flowing into the enclosure member 4, and then the inner shielding member 13 is destroyed by the propulsion device 15. Similarly, the packing 10 prevents the earth and sand in the ground 2 and the groundwater from flowing into the surrounding member 4.
Thus, by providing the inside and outside of the pair of packings 13 and 14, whether the though water stopping effect of the direction of movement of the propulsion unit, start-pit 3 is obtained. Further, in the present embodiment it has been embedded shroud 4 after drilling standing anti 3, instead of the enclosing member 4, first ground sheet pile with the packing 10 of shielding members 13 and 14 embedded in 2 may be drilling a standing anti 3 thereafter. In this case, until the drilling standing anti 3, never inside the shielding member 13 is broken by the pressure of underground soil. Further, although the insertion hole 5 formed in the enclosing member 4 is circular, it is not limited to this, and may be rectangular, and various design changes are possible. further,
Although the enclosing member 4 is formed of concrete, the enclosing member 4 may be formed of metal. As described above, according to the present invention, the cost is reduced and the construction period is shortened.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged sectional view showing a main part of a small-diameter propulsion well stop device according to the present invention. FIG. 2 is a diagram illustrating an operation of forming a small-diameter propulsion wellhead in the small-diameter propulsion wellhead water stop device according to the present invention. FIG. 3 is an exploded perspective view showing a conventional small-diameter propulsion well stop device. [Description of Signs] 2 ... Underground 3 ... Stand Up 4 ... Enclosure Member 5 ... Insertion Hole 10
... packing, 10a ... engagement holes, 11 ... bolts, 12 ... nuts, 13, 14 ... shielding members.

Claims (1)

(57) Patent Claims 1. A drilled hole in member in contact against the side wall of the standing pit cover the hole in the packing disposed between the pair of shielding members and these shielding members, The shielding member is formed of a material that can be broken by pressing of a propulsion device, and the packing is formed of a material having flexibility, and an engagement hole having an outer diameter smaller than the outer diameter of the propulsion device is formed in the packing. A small-diameter propulsion well stop device characterized in that: