JP5066281B2 - Excavation method - Google Patents

Description

  The present invention relates to an excavation method.

  In the case of tunnel excavation with a large cross section, it is expected that the slack in the front ground will increase due to the excavation, and there is a possibility that the settlement on the ground will increase. For this reason, conventionally, a R & C method for constructing a tunnel by protecting the upper part with a rectangular roof or the like in advance has been often employed immediately below the railway (for example, see Patent Document 1). In addition, a roof protect shield method has been conceived in which the upper portion is held down with a movable hood or the like.

In general, when constructing underground passages with the propulsion method, after constructing a rectangular roof and improving the ground with chemicals, there is a method of excavating this cross section while directly pulling or propelling the box, ESA method The front jacking method and the method using both of them have been put into practical use.
Similarly, in the shield method, there was a roof shield method in which excavation was performed with a small cutter having a large number of roof portions.

JP 2001-73670 A

However, the method of protecting with a rectangular roof has a limit in the construction length of the rectangular roof itself, and long-distance construction is considered difficult. Also, the process often takes a long time.
In the shield method, there is a limit to the length of the roof to be protected due to the mechanism, and a roof that exceeds the subsidence affected range may not be installed on the shield machine.

  The present invention has been made in view of such problems, and the object of the present invention is an excavation method that can excavate underground space economically in a short construction period even when the rectangular roof construction length is limited. Is to provide.

  In order to achieve the above-mentioned object, the present invention is provided with a cross-section excavator, a rectangular roof propulsion chamber disposed on an upper surface of a rear portion of the main body of the cross-section excavator, and a rear of the cross-section excavator. A propulsion jack, a rectangular roof excavator provided in front of the rectangular roof propulsion chamber and driven independently from the main cross-section excavator, and a rectangular roof propulsion jack disposed inside the rectangular roof propulsion chamber; (A) attaching the cover plate to the vicinity of the rear end of the rectangular roof excavator, and using the rectangular roof propulsion jack, the rectangular roof excavation A step (b) of installing a rectangular roof behind the rectangular roof excavator while excavating the machine, and the rectangular roof propulsion chamber while excavating the main excavator using the propulsion jack A rectangular roof recovered removal is close to the a drilling method which is characterized by comprising the step of installing the structure (c), the between the cross excavator and the propulsion jacks.

  In the step (b), the rectangular roof propulsion jack is extended to push out the preceding rectangular roof, the rectangular roof propulsion jack is pulled in, and the subsequent rectangular roof is joined to the preceding rectangular roof. It is desirable to repeat the work.

  In the step (b), it is desirable to inject a filler between the rectangular roof and the cover plate.

  In the step (c), it is desirable to inject a lubricant between the seals provided on the inner peripheral surface near the entrance of the rectangular roof propulsion chamber.

  Further, a support member is installed between the rectangular roof pushed out from the rectangular roof propulsion chamber in the step (b) and the cover plate, and pulled into the rectangular roof propulsion chamber in the step (c). It is desirable to remove the support member from the rectangular roof.

  ADVANTAGE OF THE INVENTION According to this invention, even when there is a limit in the construction length of a rectangular roof, the excavation method which can excavate underground space economically with a short construction period can be provided.

Side view of excavation mechanism 2 installed in shaft 1 Horizontal sectional view of excavation mechanism 2 starting from shaft 1 Sectional drawing of the excavation mechanism 2 by the arrow DD shown in FIG. Vertical sectional view of the excavation mechanism 2 in a state where the rectangular roof 27 has been constructed to a specified length Enlarged cross section near the sliding part Vertical sectional view of the excavation mechanism 2 during recovery of the rectangular roof 27 Vertical sectional view of the excavation mechanism 2a in a state in which the rectangular roof 27 is constructed to a specified length

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. 1 is a side view of the excavating mechanism 2 installed in the shaft 1, FIG. 2 is a horizontal sectional view of the excavating mechanism 2 started from the shaft 1, and FIG. 3 is an excavating mechanism 2 by arrows DD shown in FIG. FIG. FIG. 2 shows a cross-sectional view of the excavating mechanism 2 taken along a horizontal plane including the rectangular roof excavator 13.

  As shown in FIGS. 1 and 2, the excavation mechanism 2 includes a main excavator 15, a propulsion jack 33 provided behind the main excavator 15, a rectangular roof excavator 13, and a rear of the rectangular roof excavator 13. A rectangular roof propulsion jack 21 is provided.

  As shown in FIGS. 1 to 3, the cross-section excavator 15 is configured by arranging two excavators 11 having a rectangular cross section in two upper and lower stages. The excavator 11 is, for example, a beating excavator. As shown in FIGS. 1 and 3, the upper excavator 11a and the lower excavator 11b have a cutter 29a and a cutter 29b on the front surfaces of the main body 31a and the main body 31b, respectively. In the excavator 11a, a roof assembly machine 53, a soil removal device (not shown), and the like are disposed inside the skin plate 51a of the main body 31a. In the excavator 11b, a soil removal device (not shown) or the like is disposed inside the skin plate 51b of the main body 31b.

  As shown in FIGS. 1 and 3, in the upper excavator 11a, a convex portion 47 having a rectangular cross section and a width equal to that of the main body 31a is provided on the upper surface of the rear half of the main body 31a. The skin plate 51d of the protrusion 47 and the skin plate 51a of the main body 31a are integrally formed. The latter half of the upper surface of the skin plate 51 a of the main body 31 a functions as a partition wall 51 c between the main body 31 a and the convex portion 47. The partition wall 51c is provided with an opening 55, and the inner space of the convex portion 47 and the inner space of the main body 31a of the excavator 11a are connected via the opening 55. The inner space of the convex portion 47 is used as a rectangular roof propulsion chamber 57. A rectangular roof propulsion jack 21 is disposed in the rectangular roof propulsion chamber 57.

  As shown in FIGS. 1 and 2, the rectangular roof excavator 13 is provided in front of the convex portion 47 of the cross-section excavator 15. The rectangular roof excavator 13 is, for example, a rectangular beating machine having a flat cross section. The rectangular roof excavator 13 has a cutter 17 on the front surface of the main body 19. In the rectangular roof excavator 13, a soil discharging device 39, a sediment pressure feeding pipe 41, and the like are disposed inside the skin plate 20 of the main body 19. The rectangular roof excavator 13 has a middle folding mechanism 14. The rectangular roof excavator 13 is driven independently from the cross-section excavator 15 while controlling the vertical and horizontal postures by the center folding mechanism 14.

  As shown in FIGS. 1 to 3, a cover plate 25 is attached near the rear end 23 of the rectangular roof excavator 13. The cover plate 25 is attached to the vicinity of the rear end 23 of the upper surface 22 (FIG. 1) and the side surface 24 (FIG. 2) of the rectangular roof excavator 15.

  Next, a method for constructing an underground structure composed of a plurality of steel shells 37 on the ground 3 using the excavation mechanism 2 described above will be described. When constructing an underground structure on the ground 3 using the excavation mechanism 2, first, in the first step, the excavation mechanism 2 is installed in the shaft 1 on the start side, and a cover plate is placed near the rear end of the rectangular roof excavator 13. 25 is attached. Next, in the second step, the rectangular roof excavator 13 is advanced, and the rectangular roof 27 is installed behind the rectangular roof excavator 13. Then, in the third step, the rectangular roof 27 located in the convex portion 47 is recovered and removed while the cross-section excavator 15 is advanced, and the steel shell 37 is placed between the cross-section excavator 15 and the propulsion jack 33. Install.

  In the first step, as shown in FIG. 1, first, the starting shaft 1 is excavated in the ground 3, and the ground 3 a near the planned formation position of the wellhead 5 is improved with a chemical solution or the like. A wellhead concrete 6 is installed around a position where the wellhead 5 is to be formed, and an entrance packing 7 is provided on the wellhead concrete 6.

  After excavating the vertical shaft 1, the propulsion base 9 and the excavation mechanism 2 are installed in the vertical shaft 1. Then, mirror cutting is performed to form the wellhead 6. In order to install the excavation mechanism 2 in the shaft 1, the cross-section excavator 15 is installed on the propulsion cradle 9. Further, the propulsion jack 33 is fixed to the wall surface in the rearward direction of the vertical shaft 1, and the push ring 35 is installed in front of the propulsion jack 33. Further, the rectangular roof excavator 13 is installed in front of the convex portion 47 of the cross-section excavator 15, and the rectangular roof propulsion jack 21 is fixed inside the convex portion 47.

  When starting the excavation mechanism 2 from the vertical shaft 1, the rectangular roof excavator 13 and the cross-section excavator 15 are excavated simultaneously. The rectangular roof excavator 13 digs by pushing out the rectangular roof propulsion jack 21, and the cross-section excavator 15 digs by pushing out the propulsion jack 33.

  The rectangular roof excavator 13 excavates the ground 3 (ground 3a) while moving the cutter 17 as shown by an arrow B in FIG. The excavated soil (not shown) is taken in by a soil discharging device 39 such as a screw conveyor while managing the earth pressure, and is conveyed backward in the excavating direction using the earth and sand pressure feeding pipe 41. The cross-section excavator 15 excavates the ground 3 (the ground 3 a) with the cutter 29. The excavated soil is conveyed rearward in the excavation direction using a soil removal device (not shown) or the like.

  As shown in FIG. 1, after excavating the ground 3 a with the rectangular roof excavator 13 and the main section excavator 15, the steel shell 37 is assembled behind the main section excavator 15. A cover plate 25 having a predetermined length is attached by welding to the vicinity of the rear end 23 of the upper surface 22 and the side surface 24 of the rectangular roof excavator 13.

  FIG. 4 shows a vertical sectional view of the excavation mechanism 2 in a state where the rectangular roof 27 is constructed to a specified length. In the second step, as shown in FIGS. 2 and 4, the rectangular roof excavator 13 is advanced prior to the cross-section excavator 15, and the rectangular roof 27 is installed behind the rectangular roof excavator 13. The rectangular roof 27 has a box structure having rigidity as required, and is divided.

  In the second step, the rectangular roof propulsion jack 21 is extended to push out the preceding rectangular roof 27 by one span, the rectangular roof propulsion jack 21 is pulled in, and the succeeding rectangular roof 27 is preceded by the rectangular roof. The rectangular roof 27 is installed to a range that is not affected by excavation by the cross-section excavator 15 by repeating the operation of combining with the excavator 27.

  The following rectangular roof 27 is carried into the rectangular roof propulsion chamber 57 through the opening 55 provided in the partition wall 51c between the main body 31a and the convex portion 47 of the excavator 11a, and is coupled to the preceding rectangular roof 27. . The rectangular roofs 27 are preferably joined together by a fastening method using bolts and nuts (not shown). The fastening is performed by an operator entering the inside of the rectangular roof 27. Alternatively, an operator outside the rectangular roof 27 may perform fastening from an opening provided in the rectangular roof 27 in advance, and close the opening after completion of the fastening.

  The rectangular roof excavator 13 propels while pulling the cover plate 25 attached in the first step. The rectangular roof 27 pushed out of the rectangular roof propulsion chamber 57 (convex portion 47) by the propulsion of the rectangular roof excavator 13 is disposed in the cover plate 25 pulled by the rectangular roof excavator 13.

  FIG. 5 shows an enlarged cross-sectional view near the sliding portion. FIG. 5 is an enlarged view of a portion indicated by a range E in FIG. Since the rectangular roof 27 is pushed out from the rectangular roof propulsion chamber 57 (the convex portion 47), a void portion 63 is formed between the pit wall of the excavation pit excavated by the rectangular roof excavator 13 and the rectangular roof 27. . The cover plate 25 pulled by the rectangular roof excavator 13 prevents the upper ground 3 from sinking by the void portion 63.

In the second step, when the rectangular roof 27 is pushed out from the inside of the rectangular roof propulsion chamber 57 (convex portion 47), the filler 65, which is a filler, is applied to the void portion 63 between the rectangular roof 27 and the cover plate 25. inject. Further, a support 45 is installed between the rectangular roof 27 pushed out from the rectangular roof propulsion chamber 57 (convex portion 47) and the cover plate 25. The support 45 is installed so as to protrude from the inside of the rectangular roof 27. The filler 65 and the support 45 prevent the settlement on the road due to the bending of the cover plate 25.

  As shown in FIG. 4, the length of the cover plate 25 is the same as that of the skin plate 51a of the upper body 31a of the upper section of the cross-section excavator 15 when the rectangular roof 27 having a predetermined length is constructed. It is set to overlap. As the rectangular roof excavator 13 digs, the cover plate 25 is added in the shaft 1 until it reaches a predetermined length.

  FIG. 6 is a vertical sectional view of the excavation mechanism 2 during the recovery of the rectangular roof 27. In the third step, as shown in FIG. 6, the rectangular roof 27 located in the convex portion 47 is collected and removed while the cross-section excavator 15 is excavated, and the cross-section excavator 15 and the propulsion jack 33 are disposed. The steel shell 37 is installed in

  In the third step, the operation of extending the propulsion jack 33 to push out the preceding steel shell 37 by one span, the operation of retracting the propulsion jack 33, and the operation of coupling the subsequent steel shell 37 to the preceding steel shell 37, By repeating the above, the cross-section excavator 15 is dug to a distance where the influence on the ground is a concern.

  As shown in FIG. 5, in the cross-section excavator 15, for example, a two-stage seal 59 and a seal 67 are provided on the inner peripheral surface near the entrance of the convex portion 47. The first-stage seal 59 is fixed to the front end portion of the convex portion 47. The second-stage seal 67 is fixed behind the seal 59 in the digging direction. The seal 59 includes a seal 59a provided on the inner surface of the skin plate 51d of the convex portion 47 and a seal 59b provided on the upper surface of the partition wall 51c. The seal 67 includes a seal 67a provided on the inner surface of the skin plate 51d of the convex portion 47 and a seal 67b provided on the upper surface of the partition wall 51c.

  When the steel shell 37 is pushed out by the propulsion jack 33 and the cross-section excavator 15 is advanced, the rear portion of the rectangular roof 27 is drawn into the rectangular roof propulsion chamber 57 (convex portion 47) as shown in FIG. At this time, since the earth and sand may bite into the sliding portion and become unable to be pulled in, as shown in FIG. 5, the lubricant 69 is injected between the seal 59 and the seal 67 provided in two stages. To do.

  The support 45 protruding from the rectangular roof 27 is collected inside the rectangular roof 27 when the rectangular roof 27 is drawn into the rectangular roof propulsion chamber 57 (convex portion 47).

  The rectangular roof 27 is disassembled and collected for each span as the cross-section excavator 15 advances. When the rectangular roof 27 is collected, the rearmost rectangular roof 27 is cut off as shown by an arrow F in FIG. 6, and the opening 55 provided in the partition wall 51c between the excavator 11a and the convex portion 47 is separated. Remove from the rectangular roof propulsion chamber 57.

  When constructing an underground structure using the excavation mechanism 2, the second step and the third step are repeated as appropriate after the third step is completed. Then, after both of the rectangular roof excavator 13 and the main cross-section excavator 15 reach the reaching side shaft (not shown), the end-side mirror cutting is performed, and the rectangular roof excavator 13 and the main cross-section excavator 15 are Extrude simultaneously into a shaft (not shown) on the arrival side. The cover plate 25 pulled by the rectangular roof excavator 13 is cut and embedded in the ground 3. Thereafter, the rectangular roof excavator 13 and the cross-section excavator 15 are disassembled in a vertical shaft (not shown) on the arrival side.

  Next, a second embodiment will be described. FIG. 7 is a vertical sectional view of the excavation mechanism 2a in a state where the rectangular roof 27 is constructed to a specified length. The excavation mechanism 2a used in the second embodiment has substantially the same configuration as the excavation mechanism 2 used in the first embodiment, but as shown in FIG. A friction cut material 71 is incorporated.

  In the second embodiment, an underground structure is constructed by a method almost the same as that of the first embodiment. However, when the rectangular roof excavator 13 is advanced, as shown in FIG. A friction cut material 71 is disposed between the two. The friction cut material 71 is disposed over the entire excavation length of the rectangular roof excavator 13. The friction cut material 71 prevents joint displacement of the upper ground accompanying the advancement of the rectangular roof excavator 13, the main cross-section excavator 15, and the steel shell 37 when the earth covering of the ground 3 is small.

  In the first and second embodiments, the process of forming the rectangular roof 27 in advance and the process of excavating the cross section while collecting the rectangular roof 27 are repeated. Thereby, the construction distance of one time of the rectangular roof 27 becomes short, and even when the construction length of the rectangular roof 27 has a limit, long distance construction is possible in a short construction period. Further, by using a rational lining structure in which the split rectangular roof 27 is coupled by bolt fastening, significant cost savings can be achieved.

  As mentioned above, although preferred embodiment of the excavation method concerning this invention was described referring an accompanying drawing, this invention is not limited to this example. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

2, 2a ... Excavation mechanism 3 ... Ground 11, 11a, 11b ... Excavator 13 ... ... Rectangular roof excavator 14 ... ... Folding mechanism 15 ... ... This section excavator 17, 29, 29a, 29b ......... Cutters 19, 31, 31a, 31b ......... Main body 21 ......... Propulsion jack for rectangular roof 22 ......... Top 23 ......... Rear end 24 ......... Side 25 ......... Cover plate 27 ......... rectangular roof 33 ......... propulsion jack 37 ......... steel shell 45 ......... support 47 ......... projections 51, 51a, 51b, 51d ......... skin plate 51c ......... partition wall 55 ......... opening Part 57 ......... Rectangular roof propulsion chamber 59, 59a, 59b, 67, 67a, 67b ......... Seal 63 ......... Void part 65 ......... Filler 69 ......... Friction material 71 ......... Friction cut material

Claims (5)

This cross-section excavator,
A rectangular roof propulsion chamber disposed on the upper surface of the rear portion of the main body of the cross-section excavator;
A propulsion jack provided behind the cross-section excavator;
A rectangular roof excavator provided in front of the rectangular roof propulsion chamber and driven independently from the main-section excavator;
A rectangular roof propulsion jack provided inside the rectangular roof propulsion chamber;
Using a drilling mechanism comprising
(A) installing the excavation mechanism in a vertical shaft and attaching a cover plate near the rear end of the rectangular roof excavator;
(B) installing the rectangular roof behind the rectangular roof excavator while excavating the rectangular roof excavator using the rectangular roof propulsion jack;
A step of recovering and removing the rectangular roof located in the rectangular roof propulsion chamber while digging the cross section excavator using the propulsion jack, and installing a structure between the cross section excavator and the propulsion jack. (C),
Excavation method characterized by comprising.   In the step (b), the rectangular roof propulsion jack is extended to push out the preceding rectangular roof, the rectangular roof propulsion jack is pulled in, and the subsequent rectangular roof is joined to the preceding rectangular roof. The excavation method according to claim 1, wherein the excavation method is repeated.   The excavation method according to claim 1 or 2, wherein a filler is injected between the rectangular roof and the cover plate in the step (b).   4. The lubricant according to claim 1, wherein in the step (c), a lubricant is injected between seals provided on an inner peripheral surface near the entrance of the rectangular roof propulsion chamber. Excavation method. In the step (b), a support member is installed between the rectangular roof pushed out from the rectangular roof propulsion chamber and the cover plate,
The excavation method according to any one of claims 1 to 4, wherein in the step (c), the support member is removed from the rectangular roof drawn into the rectangular roof propulsion chamber.

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