Open shield aircraft
The open shield machine addresses sand accumulation in slide box gaps by using water-filled storage sections and adjustable valves, ensuring stable excavation face maintenance in sandy ground with groundwater.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- 植村诚
- Filing Date
- 2024-02-14
- Publication Date
- 2026-07-01
Smart Images
Figure 0007883347000001 
Figure 0007883347000002 
Figure 0007883347000003
Abstract
Description
Technical Field
[0001] The present invention relates to an open shield machine used in the open shield method for burying a concrete box for stormwater, sewage, etc. in urban areas or the like, or burying a U-shaped open channel made of concrete underground in renovation work of rivers, etc.
Background Art
[0002] As is well known, the open shield method is a highly rational method that makes use of the advantages of the excavation method (open method) and the shield method.
[0003] First, regarding the open shield machine used in the open shield method, as described in the following patent documents, basically, it is a shield machine with openings in the front, rear, and upper surfaces, consisting of left and right side wall plates and a bottom plate that connects between them and has a length similar to that of these side wall plates.
Patent Document 1
[0004] As shown in FIGS. 12 to 14, the machine body is divided into a plurality in the front-rear direction, and the front end of the rear body as the tail part 5 is fitted into the rear end of the front body as the front part 2, and it can be bent at the mutual fitting part.
[0005] The front part 2 is mainly the part where excavation is carried out, with the front end and the upper surface as open surfaces, and in the machine body, the middle folding jacks 11 are arranged left and right and in a plurality of upper and lower stages facing the rear in the rear part.
[0006] The tail part 5 is the part where the concrete box 4 is installed, and in the machine body, the propulsion jacks (shield jacks) 3 are arranged left and right and in a plurality of upper and lower stages facing the rear in the front part.
[0007] In the figure, 9 is a slide box provided at the front end of the front section 2 as a movable segmented cutting edge to prevent the side ground from collapsing during excavation. The slide box can be pushed forward from the tip of the shield machine or pulled into the tip by extending or retracting the slide jack 10 installed inside the slide box.
[0008] Furthermore, the left and right side wall panels of the front end of the front section 2 serve as sliding box storage sections 27, which function as door pockets, and the sliding box 9, which functions as a movable split blade opening, can be inserted into and removed from these sections.
[0009] In the diagram, 12 is a partition wall that separates the excavation section at the front of the open shield machine 1 from the hydraulic equipment storage section. When the shield machine 1 excavates, it pushes and compacts the excavated soil in the front section, suppressing the ground face in front and stabilizing the slope of the ground face formed in front of the excavation face. Therefore, it is useful when constructing in ground with high groundwater levels or soft ground.
[0010] In the diagram, 13 is a press bar (press angle). It is installed between the shield jack 3 and the rear concrete box 4. When the open shield machine 1 is being propelled, the shield jack 3 extends and presses against the press bar 13, and the propulsive force is evenly transmitted to the rear concrete box 4.
[0011] The bent section at the joint between the front section 2 and the tail section 5 is used for correcting direction and gradient, and for curve construction. The bent jack 11 installed at the bent section allows the front section 2 of the shield machine 1 to bend left and right or to the up and down relative to the tail section 5.
[0012] As shown in Figure 20, the open shield construction method using such an open shield machine 1 involves assembling and installing the open shield machine 1 in the launching tunnel 7, extending the propulsion jacks 3 of the shield machine 1 to take reaction force from the reaction wall 8 in the launching tunnel and advance the shield machine 1, lowering the first concrete box body 4 that will form the underground structure from above, and setting it behind the retracted propulsion jacks 3 at the tail section 5 of the shield machine 1.
[0013] The launch tunnel 7 is retained by retaining sheet piles 19. To launch the open shield machine 1, the retaining sheet piles 19 in front of the launch direction of this retaining wall are removed and the tunnel is cut open. If necessary, ground improvement may be carried out in the front part of the launch tunnel 7 by grout injection or other means.
[0014] Next, using an excavator 6 such as a shovel, soil is excavated and removed from the front or top surface while forming an excavation slope forward from inside the front section 2 of the open shield machine 1.
[0015] The installation of the concrete box 4 involves laying the concrete box 4 inside the tail section of the shield machine 1, and typically uses a lifting machine 14 such as a rough terrain crane or crawler crane.
[0016] After installing the concrete box 4 inside the tail section, (not shown in the diagram) a plastic backfill grout 15 is initially injected and filled into the gap between the inner surface of the tail section and the outer surface of the concrete box 4 from the inside of the concrete box 4 through grout holes that have been pre-installed in the concrete box 4.
[0017] The open shield machine 1 is propelled using the reaction force of the laid concrete box 4 by propulsion jacks 3 installed inside the shield machine.
[0018] Then, as the shield machine 1 is propelled, plastic backfill material 15 is injected and filled into the tail void (equivalent to the thickness of the tail bottom plate and side plates) that is generated in the ground, again through the grout holes of the concrete box body 4 as a secondary injection. Based on the above, concrete box structures 4 will be installed sequentially while culverts for rainwater, sewage, etc., are constructed underground. [Overview of the project] [Problems that the invention aims to solve]
[0019] During excavation by the open shield machine 1, the excavator 6 positioned in front of the open shield machine 1 typically excavates the face of the tunnel while forming a slope in the forward direction. At this time, the slide box 9 is extended forward from the tip of the front section 2 to prevent the ground on both sides of the excavated slope from collapsing, thereby holding down the ground on both sides of the slope.
[0020] The slide box 9 is configured to maintain the stability of the excavation face by selecting the extension length, number of slide boxes used, and locations of use according to the type of soil, ground structure, hardness, presence or absence of groundwater, and groundwater level of the excavation face. Therefore, the open shield machine 1 can be safely excavated and advanced.
[0021] Incidentally, the left and right side wall panels at the tip of the front section 2 serve as a slide box storage section 27 to house the slide box 9. A small gap 28 is provided between the storage section and the slide box to allow for smooth insertion and removal of the slide box.
[0022] However, in construction under ground conditions such as sandy ground with a high groundwater level or sandy ground with small sand particles containing groundwater, especially when the sand particles are small, sand can get stuck in the gaps 28, which can hinder the insertion and removal of the slide box 9.
[0023] If the particle size of the sand is even smaller than the gap 28, the sand will gradually flow into and accumulate in the storage section 27 along with the groundwater, making it more difficult to extend and contract the slide box 9.
[0024] In particular, when the excavation depth is great and the groundwater level is high, the groundwater pressure is also high, which exacerbates the aforementioned condition. In some cases, the slide box 9 may become unable to expand or contract, and it may no longer be able to perform its function of suppressing the loosening of the surrounding ground, requiring the slide box 9 to be replaced.
[0025] Therefore, in order to replace the slide box, it is necessary to retain the soil by using steel sheet piles or ground improvement, etc., so that the area around the slide box is in a state where it is not affected by groundwater.
[0026] Therefore, the excavation of the open shield machine has to be suspended in order to perform those operations, etc., and the associated costs are also incurred, resulting in uneconomical situations.
[0027] An object of the present invention is to solve the above-mentioned conventional disadvantages. An open shield machine having front, rear, and upper surfaces open, which consists of left and right side wall plates and a bottom plate that connects between them with a length similar to that of these side wall plates. The machine body is divided into a plurality in the front-rear direction, and the front end of the rear machine body as a tail part is fitted into the rear end of the front machine body as a front part, and it can be bent at the mutual fitting part. The left and right side wall plates at the front end of the front part are formed as slide box storage parts as pocket bags, and in an open shield machine provided with a movable divided blade edge that stores a slide box so as to expand and contract back and forth in this slide box storage part, even in a sandy ground with groundwater, the slide box can be smoothly expanded and contracted, so that the loosening of the face ground side part in front of the front part can be suppressed and the function can be fully exerted, and the object is to provide an open shield machine that can stably maintain the slope of the face ground during construction.
Means for Solving the Problems
[0028] In order to achieve the above object, the present invention according to claim 1 is an open shield machine having front, rear, and upper surfaces open, which consists of left and right side wall plates and a bottom plate that connects between them with a length similar to that of these side wall plates. The machine body is divided into a plurality in the front-rear direction, and the front end of the rear machine body as a tail part is fitted into the rear end of the front machine body as a front part, and it can be bent at the mutual fitting part. The left and right side wall plates at the front end of the front part are formed as slide box storage parts as pocket bags, and in an open shield machine provided with a movable divided blade edge that stores a slide box so as to expand and contract back and forth in this slide box storage part, A submersible pump is installed in a water tank placed on the rear of the front section, and the submersible pump is connected to each of the slide box storage sections located below the groundwater level by piping. The gist is that the slide box storage part is made capable of being filled with water. That's what it mainly means.
[0029] According to the present invention as described in claim 1, in construction in ground conditions such as sandy ground with groundwater, even if sand flows in through the gap between the slide box and the slide box storage section along with the flowing groundwater and accumulates in the box storage section, this sand can be discharged by water poured into the slide box storage section.
[0030] The gist of the present invention as described in claim 2 is that a lid that opens and closes forward is provided on the front end of the lower or side surface of each slide box.
[0031] According to the present invention as described in claim 2, a lid that opens and closes forward is hinged to the front end of the bottom or side of each slide box, so that the water poured in can be stored until it reaches a certain water pressure, and the lid can be opened using the water pressure, allowing the accumulated sand to be discharged all at once.
[0032] The present invention as described in claim 3 is Aquarium The gist of this is that water is supplied by the water pressure difference due to the difference in water head at each of the aforementioned slide box locations below the groundwater level, or by the operation of the submersible pump.
[0033] According to the present invention as described in claim 3, the difference in water head between the water tank placed on the rear of the front section of the open shield machine and the water pressure of the slide box below the groundwater level causes the water stored in the water tank to be sent into the box storage section through connected piping. Then, the sand accumulated in the box storage section can be discharged by the water pressure.
[0034] Furthermore, if the water pressure at a depth below the groundwater level in the slide box is greater than the water head pressure due to the height difference with the water tank, sand will continue to accumulate in the slide box storage area at that depth. However, by operating the submersible pump installed in the water tank, the water pressure from the pump forces the water into the box storage area, allowing the sand accumulated in the box storage area to be discharged through the gaps.
[0035] The present invention as described in claim 4 is Each box storage compartmentThe gist of this system is to install valves adjacent to each of the box housings in the connected piping, and to supply water by opening and closing these valves.
[0036] According to the present invention as described in claim 4, since a valve is installed on the box storage side of the piping connected to each slide box storage section, by selecting the valve of the box storage section where sand is accumulating and setting it to the "open" state, the sand can be discharged only from the box storage section where sand is accumulating.
[0037] Furthermore, by adjusting the open / closed state of the valve in the piping connected to the box storage section where the sand is accumulating, the amount of water supplied to the box storage section can be adjusted, allowing the accumulating sand to be discharged smoothly and quickly through the gaps. [Effects of the Invention]
[0038] As described above, the open shield machine of the present invention allows for smooth extension and retraction of the slide box even in sandy ground with groundwater present, by easily and quickly discharging the sand into the slide box housing section that houses the slide box. Therefore, the slide box can reliably hold down the ground on the side in front of the front section.
[0039] This eliminates the need to replace the slide boxes, allowing for safe stabilization of the excavation face and the advancement of the open shield machine. [Brief explanation of the drawing]
[0040] [Figure 1] A longitudinal cross-sectional side view showing one embodiment of the open shield machine of the present invention. [Figure 2] This is a cross-sectional plan view showing one embodiment of the open shield machine of the present invention. [Figure 3] This is an enlarged longitudinal cross-sectional plan view of the slide box portion before extension, showing one embodiment of the open shield machine of the present invention. [Figure 4]A longitudinal cross-sectional side view showing one embodiment of the open shield machine of the present invention when the slide box is extended. [Figure 5] A cross-sectional plan view showing one embodiment of the open shield machine of the present invention when the slide box is extended. [Figure 6] This is an enlarged cross-sectional plan view of the extended slide box portion, showing one embodiment of the open shield machine of the present invention. [Figure 7] This is a longitudinal cross-sectional side view of a slide box with a hinged lid. [Figure 8] This is a view along line AA in Figure 7. [Figure 9] A longitudinal cross-sectional side view of the slide box in its extended state, with the lid attached by hinges, is shown. [Figure 10] This is a view along the line BB in Figure 9. [Figure 11] This is a cross-sectional plan view of a slide box with a hinged lid. [Figure 12] This is a cross-sectional plan view of a conventional open shield machine. [Figure 13] This is a longitudinal cross-sectional side view of a conventional open shield machine. [Figure 14] This is a front view of a conventional open shield aircraft. [Figure 15] This is an enlarged view of section A in Figure 12. [Figure 16] This is a plan view of the slide box section of a conventional open shield machine. [Figure 17] This is a cross-sectional plan view of the slide box section of a conventional open shield machine. [Figure 18] This is a view along line AA in Figure 17. [Figure 19] This is a view along the line BB in Figure 17. [Figure 20] This is a schematic diagram illustrating the construction method of the open shield tunneling system. [Figure 21] This is a perspective view of an open shield aircraft. [Figure 22] This is a cross-sectional plan view showing the inflow of groundwater, etc., when the slide box is extended. [Figure 23]This is a longitudinal cross-sectional side view showing the inflow of groundwater, etc., when the slide box is extended. [Figure 24] This is an enlarged cross-sectional plan view showing the inflow of groundwater, etc., when the slide box is extended. [Modes for carrying out the invention]
[0041] The embodiments of the present invention will be described in detail below with reference to the drawings. Figure 1 is a longitudinal cross-sectional side view showing an embodiment of the open shield machine of the present invention, and Figure 2 is a transverse plan view of the same, in which the same components as those in Figures 12 to 14 showing the conventional example are denoted by the same reference numerals.
[0042] The basic shape of the open shield machine 1 is the same as the conventional example, with the machine body divided into multiple sections in the front-rear direction, and the front end of the tail section 5 fitting into the rear end of the front section 2, making the interlocking section 16 bendable. Note that 11 is an interlocking jack, 12 is a bulkhead, and 13 is a press bar (press angle).
[0043] In the tail section 5, propulsion jacks (shield jacks) 3 are positioned on both sides of the aircraft, facing backward from the front, and also arranged in multiple vertical rows.
[0044] In the figure, 9 is a slide box, which is a movable segmented cutting edge provided at the front end of the front section 2 to prevent the side ground from collapsing during excavation. The left and right side wall plates at the front end of the front section 2 serve as a sliding box storage section 27, which acts as a door pocket. 10 is a slide jack that extends and retracts the slide box 9 back and forth.
[0045] As described above, the open shield construction method using such an open shield machine 1 involves the steps of excavating and removing the sand in front of the opening on the front or top of the open shield machine 1, extending the propulsion jacks 3 to use the concrete box 4 as a reaction force to advance the open shield machine 1, and lowering a new concrete box 4 from above behind the retracted propulsion jacks 3 inside the tail section 2 of the shield machine 1 to set it in place, and repeating these steps as appropriate to sequentially bury the concrete box assemblies in a vertical line.
[0046] The open shield machine 1 of the present invention allows water to be injected into the slide box storage section 27.
[0047] A water tank 21 with a submersible pump 22 installed is placed on the rear of the front section 2 of the open shield machine 1, and the submersible pump 22 is connected to a slide box storage section 27 located below the groundwater level by piping 23, so that water can be supplied into the box storage section 27.
[0048] The submersible pump 22 and each of the slide box housing sections 27 located below the groundwater level are connected by piping 23, and water is supplied by the water pressure difference between the water tank 21 and the slide box housing section 27 located below the groundwater level, or by the movement of the submersible pump 22.
[0049] The piping 23 branches appropriately from the main pipe from the water tank 21 and connects to each of the slide box storage sections 27.
[0050] In this way, if the box storage section 27 is filled with water through the piping 23, even when the submersible pump 22 is not operating, if there is a sufficient difference in water head between the water tank 21 and the depth of the box storage section 27 which is below the groundwater level, water from the water tank 21 will be sent from the water tank 21 to the box storage section 27 through the piping 23 by the siphon principle.
[0051] Therefore, even if sand enters and accumulates in the box storage section 27 along with groundwater through the gap 28 between the slide box 9 and the box storage section 27 below the groundwater level, the water in the water tank 21 is supplied, so the accumulated sand can be discharged from the gap 28.
[0052] Furthermore, if the difference in water head between the slide box storage section 27, which is below the groundwater level, and the water in the tank 21 is small, and the sand accumulated in the box storage section 27 cannot be discharged due to the difference in water head and the siphon principle as described above, the submersible pump 22 is operated so that the water pressure from which it is supplied can discharge the accumulated sand from the gap 28.
[0053] As a second embodiment of the present invention, a valve 24 is installed on the side of the box storage section 27 of the piping 23 connected to each slide box storage section 27.
[0054] By installing valves 24 on the box storage section 27 side of the piping 23 connected to each slide box storage section 27 in this manner, the valve 24 of the box storage section 27 where sand is accumulating can be selected and set to the "open" state, while the other valves 24 are set to the "closed" state, thereby allowing the sand from only the box storage section 27 where sand is accumulating to be discharged through the gaps 28 of the box storage sections 27.
[0055] Furthermore, by adjusting the open / closed state of the valve 24 in the piping 23 connected to the box storage section 27 where the sand is accumulating, the amount of water supplied to the box storage section 27 can be adjusted, allowing the accumulated sand to be discharged smoothly and quickly through the gap 28. Note that any type of valve 24 may be used, such as a globe valve, ball valve, or butterfly valve.
[0056] Furthermore, although not shown in the diagram, for slide boxes 9 located above the groundwater level, if the ground conditions involve small sand particles and it is necessary to frequently extend and retract the slide box 9 during excavation by the open shield machine 1, and sand clogs the gap 28 in the box housing section 27, preventing the slide box 9 from extending or retracting, an additional pipe 23 is connected to the slide box housing section 27, and water is supplied from the submersible pump 22 to clean the clogged gap 28 and discharge the sand.
[0057] As a third embodiment of the present invention, a lid material 26 that opens and closes forward is provided by hinge on the front end of the lower or side surface of each slide box.
[0058] The lid 26 is hinged to the front end of the slide box 9 so that it opens and closes forward. When the slide box 9 is extended, the lid 26 opens forward, and when the slide box 9 is stored in the slide box storage section 27, it closes.
[0059] If the excavation depth of the open shield machine 1 is deep, it is expected that a large amount of sand will flow into and accumulate in the slide box storage section 27 due to the high groundwater pressure.
[0060] In that case, there is a risk that sand may not be completely discharged from the gap 28 in the box storage section 27, which could hinder the expansion and contraction of the slide box 9. However, since the lid material 26 opens forward due to the water pressure from the tank 21, in addition to discharge from the gap 28, a large amount of accumulated sand can be smoothly discharged from there.
[0061] Furthermore, since it was anticipated that the slide box 9, located at the bottom, might not open if the lid 26 were installed on the side due to the ground below or soil and debris accumulated in front of the partition wall 12, the lid 26 was installed on the side of the slide box 9. [Explanation of Symbols]
[0062] 1…Open shield aircraft 2…Front section 3…Propulsion jacks (shield jacks) 4...Concrete box body 5...Tail section 6…Excavator 7…Starting shaft 8…Reaction wall 9…Slide box 10...Slide jack 11...Folding jack 12... Partition wall 13... Press bar (press angle) 14…Lifting equipment 15…Backfill injection material 16...Bend in the middle 17...Backfill soil 18...Groundwater level 19...Retaining sheet piles 20...Groundwater and sediment inflow 21...Water tank 22... Submersible pump 23... Piping 24... Valve 25... Water supply 26...Lid material 27...Slide box storage section 28...Gap
Claims
1. An open shield machine having an open front, rear, and top, consisting of left and right side wall plates and a bottom plate of the same length as these side wall plates connecting them, the machine body is divided into multiple parts in the front-rear direction, the front end of the rear machine body as the tail section fits into the rear end of the front machine body as the front section and is bendable at the mutual fitting section, the left and right side wall plates of the front end of the front section are formed as sliding box storage sections as door pockets, and a movable dividing blade opening is provided in this sliding box storage section so as to expand and contract the sliding boxes front and rear, an open shield machine characterized in that a submersible pump is installed in a water tank placed on the rear of the front section, the submersible pump is connected by piping to each of the sliding box storage sections below the groundwater level, and water can be injected into the sliding box storage sections.
2. The open shield machine according to claim 1, wherein a lid that opens and closes forward is provided on the lower surface or the front end of the side of each slide box.
3. The open shield machine according to claim 1 or claim 2, which is operated by supplying water by the water pressure of the head difference between the water tank and each of the slide box positions below the groundwater level, or by supplying water by the movement of the submersible pump.
4. An open shield machine according to claim 1 or claim 2, wherein a valve is installed adjacent to each box storage section of the piping connected to each box storage section, and water is supplied by opening and closing the valve.