Open shield machine and open shield construction method using the same

Abstract

To provide an open shield machine and an open shield construction method using the same, which are safe and efficient without the use of an excavator, for laying a box conduit in a narrow space close to houses, repairing an existing fence conduit, etc.SOLUTION: In an open shield machine 1, a body consisting of left and right side wall panels 1a and a bottom panel 1b is divided in the front / rear direction into a front machine 17 and a tail machine 18, a front end of the tail machine 18 is fitted into a rear end of the front machine 17 to make it bendable, and propulsion jacks 3 are arranged on the left and right sides in a front portion inside the tail machine 18 so as to face backward and are arranged in multiple vertical levels. A frame 27 provided with beams 30 in the front / rear direction is formed so as to extend upward from an upper end of the tail machine 18, a traveling beam on which a chain block 28 can travel is horizontally installed across the front / rear beams 30, and an excavation clamshell bucket 31 is suspended from the chain block 28.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an open shield machine and an open shield method using the same.

Background Art

[0002] The open shield method is a rational method that takes advantage of the merits of the excavation method (open cut method) and the shield method, and its schematic is shown in FIGS. 8 to 17.

[0003] In the figure, 1 is an open shield machine, which is a shield machine with openings in the front, rear, and upper surfaces, consisting of left and right side wall plates 1a and a bottom plate 1b connecting these side wall plates 1a as shown in FIGS. 11 to 13.

[0004] The open shield machine 1 forms the tips of the side wall plates 1a and the bottom plate 1b as cutting edges 2, and also arranges propulsion jacks 3 vertically side by side with the rear ends facing backward near the center or the rear end of the side wall plates 1a.

[0005] Further, the open shield machine 1 divides the machine body into a front machine 17 and a tail machine 18 in the front-rear direction, and the front end of the tail machine 18 is fitted into the rear end of the front machine 17 to form a middle folding part 47 at the mutual fitting part to make it bendable. A middle folding jack 20 is arranged at this middle folding part 47.

[0006] The front machine 17 mainly serves as an excavation part, and the tail machine 18 arranges the propulsion jacks 3 and becomes a tail part 19 as a lifting and lowering installation part for the concrete casing 4 and the U-shaped open channel 42.

[0007] In the figure, 16 is a slide jack of a slide earth retaining plate provided at the front end of the front machine 17, and 23 is a pressing angle (press bar) using H-shaped steel or the like. In the figure, 48 is a rear earth retaining plate when the concrete casing 4 comes out of the tail machine 18 as the open shield machine 1 advances, and the upper part of the concrete casing 4 is backfilled inside this.

[0008] The general procedure for the open shield tunneling method is as follows: First, as shown in Figure 14, the open shield machine 1 is assembled in a predetermined position in the launch shaft 8. After assembly, the propulsion jacks 3 of the open shield machine 1 are extended to take reaction force from the reaction wall 9 in the launch shaft and advance the open shield machine 1. The first concrete box body 4 that will form the underground structure is lowered from above and set behind the retracted propulsion jacks 3 in the tail section 19 of the open shield machine 1.

[0009] The concrete box bodies 4, which are laid sequentially within the launch shaft 8, are propelled forward by the open shield machine 1, and after exiting the launch shaft 8, they are propelled to a predetermined distance and temporarily laid as reaction force transmission materials until the propulsion force of the open shield machine is no longer transmitted to the reaction wall 9 within the launch shaft 8. They are removed when the propulsion reaction force is no longer transmitted to the reaction wall 9.

[0010] The launch shaft 8 is constructed of earth retaining wall 49. To launch the open shield machine 1, a portion of this front earth retaining wall is cut away, but if necessary, ground improvement 11 may be applied to the front portion of the launch shaft 8 by grout injection or other means.

[0011] Next, after cutting a portion of the retaining wall in front of the launch shaft 8, as shown in Figure 15, the soil in front of the open shield machine 1 is excavated from above using an excavating machine 6 such as a shovel and removed.

[0012] Simultaneously with or after this soil removal process, the propulsion jacks 3 are extended to advance the open shield machine 1. In this advancement process, a press bar (press angle) 23 (see Figures 8 and 11) made of a frame using box steel or shaped steel is placed in front of the concrete box body 4.

[0013] Then, after the open shield machine 1 moves forward by the length of one concrete box, the second concrete box 4 is lowered and set in front of the first concrete box 4 into the tail section 19 of the open shield machine 1 using the lifting and lowering equipment 24, as shown in Figure 16.

[0014] The following excavation and soil removal processes, advancement processes, and concrete box structure 4 setting processes are repeated as appropriate, and the concrete box structures 4 are sequentially left in the ground in a vertical line as the open shield machine 1 advances. As shown in Figure 16, the top surface of the concrete box structures 4 is backfilled and the surface is paved.

[0015] In the concrete box structure 4 setting process, after the concrete box structure 4 is set inside the tail machine, the backfill grout 25 is injected as a primary injection, and the backfill grout 25 is injected as a secondary injection to fill the voids generated in the ground during the excavation, soil removal, and forward movement processes of the open shield machine 1.

[0016] As described above, once the open shield machine 1 reaches the receiving tunnel 13, as shown in Figure 17, it is removed to complete the construction.

[0017] Although not shown in the diagram, the concrete box body 4 is made of reinforced concrete and is a single rectangular structure consisting of a left slab, a right slab, a top slab, and a bottom slab, with the front and rear surfaces open.

[0018] Furthermore, pre-installed grout holes are provided near the center of each of the left and right side slabs and the bottom slab. The backfill grout material 25 is injected and filled through these grout holes as primary and secondary injections, respectively, into the tail voids that occur in the ground after the concrete box body 4 is installed inside the tail section 19 and as the open shield machine 1 excavates.

[0019] Figures 8 to 12 show the construction situation in the open shield method, where houses are close together on both sides, making it impossible for the lifting and hoisting equipment 24 for lowering and setting the U-shaped open channel 42 to enter or rotate, and the excavator 6 cannot be positioned in front of the open shield machine 1, such as in the improvement work of existing fence channels and rivers.

[0020] As shown in the diagram, a frame 27 is installed on the upper end of the tail machine 18 of the open shield machine, and an excavator 6 is mounted on top of the front machine 17, making construction possible even under the aforementioned conditions. This method is commonly used in open shield construction under the following construction conditions and has a proven track record.

[0021] Furthermore, the following are patent documents that are used under the aforementioned construction conditions, such as confined spaces. [Patent Document 1] Patent No. 3194190

[0022] The aforementioned Patent Document 1 describes a shield machine in which a frame for lowering a box body is installed at the upper end of the box body installation section (tail section) of the open shield machine, the frame being made up of columns and beams, and a hoisting machine such as a chain block is provided to be able to move back and forth and left and right.

[0023] Patent Document 1 describes a shield machine equipped with a gantry-type crane for lowering concrete boxes, which is mounted on the upper end of the open shield machine's tail section. This is intended to address situations where construction is not possible in narrow spaces, such as when there is not enough space for a truck crane (lifting machine) to lower concrete boxes, or when there are buildings nearby that prevent the truck crane from rotating.

[0024] Furthermore, by extending the beam members of the frame to the rear and creating a box lifting section protruding from the rear of the open shield machine, it is made easier to lift the box that has been transported by trolley or the like from the rear of the open shield machine.

[0025] Furthermore, by extending the beam members of the box-shaped lifting section forward, it becomes possible to receive the excavated soil from the face of the open shield machine in front of the excavator into a bucket, then lift the bucket with the frame, move it to the rear, and transfer the contents to a dump truck or the like. [Overview of the Initiative] [Problems that the invention aims to solve]

[0026] In Patent Document 1, while the frame allows for smooth installation of the box structure, the beam members of the box structure lifting section are simply projected forward. This necessitates loading and transporting the excavated soil into buckets or the like, increasing the number of work types and working time.

[0027] In addition, the deeper the depth of embedding the casing, the larger the excavator has to be, and in a narrow space, it may interfere with the turning of the excavator. Furthermore, depending on the excavation depth, the arm of the excavator may not reach the predetermined excavation depth and excavation may not be possible.

[0028] Similarly, in the cases shown in FIGS. 8 to 12, the deeper the depth of embedding the casing, the larger the excavator has to be, and in a narrow space, it may interfere with the turning of the excavator due to adjacent buildings or the like, or the arm of the excavator may not reach and excavation may not be possible.

[0029] Also, during excavation, the excavator turns 180° and extends the arm of the excavator backward so as not to contact the support columns of the casing hanging equipment in the structure, and the excavated soil is loaded into the soil removal bucket, so excavation and loading time are required and the work efficiency deteriorates.

[0030] Furthermore, since the excavator is mounted on the front machine of the open shield machine, depending on the proximity to houses or the degree of narrowness, the situation in front is difficult to see for those other than the operator of the excavator, so other workers cannot confirm the situation of the face ground or the like, and there are cases where the actual measurement and confirmation of the position and height of the front part of the open shield machine by surveying cannot be performed.

[0031] An object of the present invention is to solve the above disadvantages, and to provide an open shield machine with good work efficiency that can perform excavation without hindrance such as contact with surrounding buildings or casing hanging equipment even in a narrow place where buildings or the like are close, and further, can perform excavation even at an excavation depth where the arm of the excavator cannot reach, and an open shield method using the same.

Means for Solving the Problems

[0032] To achieve the above objective, the present invention as described in claim 1 is an open shield aircraft in which the aircraft body, consisting of left and right side wall plates and a bottom plate, is divided in the front-rear direction into a front aircraft and a tail aircraft, the front end of the tail aircraft is fitted into the rear end of the front aircraft to make it bendable, and propulsion jacks are arranged on the front side of the inside of the tail aircraft, facing rearward, and are arranged in multiple vertical stages, and a frame structure with beam members in the front-rear direction is formed from the upper end of the tail aircraft upward, Lifting and lowering equipment consisting of an electric chain hoist and an electric chain hoist hook. A travel beam, which is installed to allow movement, is horizontally mounted on the beam in the front-to-back direction. Clamshell bucket The lifting and raising equipment On the electric chain hoist hook Hanging, A sliding earth retaining plate is provided at the cutting edge of the front machine, and the front end of the beam member in the front-rear direction extends forward beyond the tip of the sliding earth retaining plate, which extends to its maximum extent from the front end of the cutting edge of the front machine. This is a summary.

[0033] According to the invention of claim 1, Open shield aircraft Attached to the frame installed on the tail unit Electric chain block hook of a lifting and lowering equipment consisting of an electric chain block and an electric chain block hook Suspended Clamshell bucket Therefore, the excavation face in front of the cutting edge can be performed without using a shovel-type excavating machine.

[0034] Furthermore, since the clamshell bucket is suspended by lifting and lowering equipment installed on the frame, Electric chain hoist If you adjust the length of the suspension wire, Shovel-type excavating heavy machine Even at depths that the arm cannot reach, the clamshell bucket can be suspended at that depth, allowing for sufficient excavation.

[0035] Furthermore, by fully extending the sliding earth retaining plate from the front end of the cutting edge of the front machine, and from a position beyond the tip of the sliding earth retaining plate, the clamshell bucket suspended from the lifting and lowering equipment can be used to form a slope toward the front machine side during excavation. In other words, with the sliding earth retaining plate fully extended to suppress loosening of the ground on the side of the cutting edge, excavation can be performed while forming a slope while maintaining the stability of the ground at the cutting edge with the clamshell bucket.

[0036] The present invention as described in claim 2 is Clamshell bucket It is hydraulically operated, and the propulsion jack installed on the open shield machine and the clamshell bucket are The open shield aircraft is mounted on the rear of the front unit Each is connected to a separate hydraulic pump. death,The aforementioned promotion The extension of the jacks propels the open shield machine and opens and closes the clamshell bucket. While constantly checking the conditions of the sluice gate, Operate simultaneously or individually can This is the gist of it.

[0037] According to the present invention as described in claim 2, Clamshell bucket Because it is hydraulically operated, it can reliably excavate and grasp the soil at the excavation face and move it to the excavated soil removal bucket positioned at the rear of the open shield machine, enabling smooth excavation and excavated soil removal operations.

[0038] In addition, the propulsion jacks and the hydraulically operated clamshell bucket are Since it is connected to each individual hydraulic pump mounted on the rear of the front unit of the open shield machine, from beside each individual hydraulic pump mounted on the rear of the front unit, This allows for simultaneous operation of advancing the open shield machine and excavating the excavation face in front of the shield machine's cutting edge, enabling smooth excavation work by the open shield machine.

[0039] Furthermore, the aforementioned promotion The extension of the jacks allows for the simultaneous or independent operation of the propulsion of the open shield machine and the opening and closing of the clamshell bucket. Therefore, even if the excavation face in front of the cut-off end of the open shield machine is prone to loosening due to conditions such as soil properties and groundwater level, the excavation face can be temporarily compacted and stabilized by propulsion of the open shield machine alone, while continuously monitoring the condition of the excavation face. Clamshell bucket This allows for prioritizing excavation work. Therefore, by constantly monitoring the condition of the excavation face and responding flexibly to the situation, reliable excavation work can be carried out while ensuring the stability of the excavation face.

[0040] The present invention as described in claim 3 is Clamshell bucket It is a hydraulically operated opening and closing system, and the clamshell bucket is connected to a hydraulic pump that operates the propulsion jack installed on the open shield machine. The clamshell bucket is opened and closed by either a clamshell bucket switching valve connected to a power generator via a power cable, or by a hydraulic pump. The gist of this is that the clamshell bucket can be operated by supplying oil from the hydraulic pump.

[0041] According to the present invention as described in claim 3, the open shield machine is equipped with promotion The jack operates using hydraulic fluid discharged from a hydraulic pump, and the flow of the hydraulic fluid is switched in the piping from the clamshell bucket to the hydraulic pump. Clamshell bucket switching valve By using this device as an intermediary, it becomes possible to open and close the clamshell bucket.

[0042] Clamshell bucket Because it is hydraulically operated, it can reliably excavate and grip the soil at the excavation face and move it to the excavated soil removal bucket located at the rear of the shield machine, enabling smooth excavation and excavated soil removal operations. Furthermore, since the hydraulically operated clamshell bucket is connected to the hydraulic pump used to operate the propulsion jacks, the equipment can be simplified without increasing the number of hydraulic pumps.

[0043] As long as the piping is hydraulically designed, the switching valve can be manual or electromagnetic, and it is possible to use the power supplied by the hydraulic pump and electric chain hoist to operate an electromagnetically operated switching valve and switch to open and close the clamshell bucket.

[0044] The present invention as described in claim 4 is The process involves extending the sliding earth retaining plate to its maximum extent forward from the cutting edge of the front machine of the open shield machine, Lifting and raising equipment installed on the running beams of a frame structure with beams in the front-to-back direction Clamshell bucket Hang it up, Move to the tip of the fully extended sliding earth retaining plate, The aforementioned clamshell bucket Beyond the tip of the fully extended sliding earth retaining plate, the excavation site in front of the front machine is directed toward the front machine, forming a concave slope and excavating. The process involves the excavation and soil transport / removal process, which involves moving the soil to the soil transport facility located at the rear after hoisting and loading it, the propulsion process by extending the propulsion jacks of the open shield machine, and the removal and movement process of the clamshell bucket after propelling the entire length of one section, and transporting the soil to the rear of the open shield machine. Concrete box Alternatively, the process involves repeatedly lifting, moving, and suspending the vehicle into the tail section using a U-shaped open channel frame. Concrete box Alternatively, the gist of it is to install a U-shaped open channel.

[0045] According to the present invention as described in claim 4, without using an excavator, The sliding earth retaining plate is extended to its maximum extent forward from the cutting edge of the front machine, The rock face in front of the cutting edge of the open shield machine Because the excavation process creates a concave slope, it is possible to excavate while maintaining the stability of the excavation face.Because there is no risk of contact with nearby buildings or structures due to the rotation of the excavator, excavation and soil removal can be carried out safely and efficiently. Furthermore, since no excavator is used, there are no rental fees for excavators or labor costs for excavator operators, making it economical.

[0046] For existing culverts and river improvement projects, open shield machines are typically used. of front machine Although construction is carried out by mounting an excavator, in this invention the excavator of Since it is not mounted on the open shield machine, it allows for thorough confirmation of the excavation conditions and soil properties of the excavation face in front of the open shield machine's cutting edge, and enables quick responses to changes in these conditions.

[0047] Furthermore, in order to manage the propulsion behavior of the open shield machine during excavation, Open shield aircraft A sighting target for surveying is set up near the tip, and the survey is performed from the rear using front surveying equipment, but the excavator The front unit is not equipped with it. Therefore, it does not interfere with the sighting of surveying equipment, and surveying can be carried out without any problems.

[0048] Furthermore, in the case of existing culverts or river improvement work in close proximity to houses and other structures, it is necessary to move or evacuate the excavator when construction progresses close to the target area, but this is not necessary with the present invention. [Effects of the Invention]

[0049] As described above, the open shield machine and the open shield construction method using the same of the present invention are from excavation Concrete box Alternatively, it allows for efficient, safe, and economical construction, including the laying of U-shaped open channels. [Brief explanation of the drawing]

[0050] [Figure 1] This is a plan view showing one embodiment of the open shield machine and the open shield construction method using the present invention. [Figure 2] This is a longitudinal cross-sectional side view showing an embodiment of the open shield machine and the open shield construction method using the present invention during excavation by the open shield machine. [Figure 3] This is a longitudinal cross-sectional side view of the open shield machine and the open shield construction method using the present invention during the installation of a U-shaped open channel. [Figure 4] A longitudinal cross-sectional side view showing the open shield machine of the present invention. [Figure 5] This is a front view of the open shield machine of the present invention. [Figure 6] This is a longitudinal cross-sectional side view showing the situation when the clamshell bucket is removed in the open shield tunneling method of the present invention. [Figure 7] Another embodiment of the open shield machine of the present invention is shown in the schematic diagram of the hydraulic and electrical circuits. [Figure 8] This is a plan view of the conventional open shield tunneling method. [Figure 9] This is a longitudinal cross-sectional view showing the conditions during excavation using the conventional open shield tunneling method. [Figure 10] This is a longitudinal cross-sectional side view showing the situation during the installation of a U-shaped open channel using the conventional open shield tunneling method. [Figure 11] This is a front view of the conventional open shield tunneling method. [Figure 12] This is a longitudinal cross-sectional side view showing the situation when the excavator is removed in a conventional open shield tunneling method. [Figure 13] This is a perspective view showing the construction status of the open shield tunneling method. [Figure 14] This is a side view showing the first step of the open shield tunneling method. [Figure 15] This is a side view showing the second step of the open shield tunneling method. [Figure 16] This is a side view showing the third step of the open shield tunneling method. [Figure 17] This is a side view showing the fourth step of the open shield tunneling method. [Modes for carrying out the invention]

[0051] The embodiments of the present invention will be described in detail below with reference to the drawings. Figure 1 is a plan view showing one embodiment of the open shield tunneling method of the present invention, and Figure 2 is a longitudinal side view of the open shield machine during excavation. The same reference numerals are used for the same components as in Figures 7 to 15 which show the conventional example.

[0052] Figure 1 shows an open shield machine 1, which consists of a front machine 17 and a tail machine 18. The front part of the tail machine 18 is fitted into the rear part of the front machine 17, and the fitting part is a bendable section 47. Both the front machine 17 and the tail machine 18 consist of a bottom plate 1b and left and right side walls 1a, and the top is open.

[0053] The cutting edge of the front machine 17 is equipped with a sliding earth retaining plate 16a with a sliding jack 16 installed inside. The sliding earth retaining plate 16a with the sliding jack 16 installed inside can extend forward from the front end of the cutting edge of the front machine 17, and has the function of suppressing the loosening of the side ground when the excavation face in front of the cutting edge 2 is performed while forming a slope.

[0054] Furthermore, the propulsion jacks 3 were positioned facing rearward on the folding section 47 side of the tail unit 18, shifted to the left and right, and arranged in multiple vertical stages.

[0055] As shown in Figures 2 to 5, a frame 27 consisting of columns and beams is erected at the upper ends of both side walls of the tail unit 18, and a beam 30 running in the front-to-back direction is provided on the inner upper part of each of the left and right columns as a lifting and lowering device, serving as a travel beam 41 for the electric chain block 28.

[0056] A traveling beam 41 was horizontally mounted on the aforementioned front-to-back beam member 30 so as to allow the electric chain hoist 28 to travel along it. 28 Install it.

[0057] While an electric chain hoist 28 is preferred as the lifting and lowering equipment, a wire hoist, lever hoist (registered trademark), electric winch, or the like may be used as alternatives.

[0058] As shown in Figure 5, the sliding earth plate 16a extends forward from the cutting edge of the front machine 17 to a maximum of 1.0 m or 1.5 m, depending on the sliding earth retaining plate 16a that is installed. The front end of the beam member 30 in the front-rear direction extends beyond the tip of the fully extended sliding earth retaining plate 16b.

[0059] By extending the front-to-back beam members 30 to the aforementioned positions, the sliding retaining plate 16a can be extended to almost its maximum extent from the end of the cutting edge 2 during excavation of the face of the tunnel in front of the cutting edge 2, and the excavation clamshell bucket can move to a position beyond the tip of the sliding retaining plate 16a. Therefore, by forming a concave slope toward the front machine 17 side, from the tip of the fully extended sliding retaining plate 16b, while changing the slope gradient according to the condition of the ground, excavation can be performed while maintaining the stability of the face of the tunnel.

[0060] Furthermore, as shown in Figure 3, the rear end of the beam member 30 in the front-rear direction extends to a position where the U-shaped open channel 42, which has been transported to the rear end of the tail section of the open shield machine 1, can be suspended.

[0061] In this embodiment, the clamshell bucket 31 for excavation uses a hydraulic opening and closing mechanism and is suspended from the electric chain hoist hook 29 of the electric chain hoist 28. Clamshell bucket They may use wire-operated clamshell buckets, etc., by attaching other equipment.

[0062] At the rear of the front unit 17 of the open shield machine 1, there are two hydraulic pumps: one for propulsion of the open shield machine 1 and another for a hydraulically operated clamshell bucket, etc.

[0063] A generator 32 is installed at the front of the tail unit 18 and is connected to equipment such as the electric chain hoist 28, hydraulic pump 33, bucket control switch 35, and hydraulic control panel on the frame 27.

[0064] The electric chain hoist 28 is operated via a power cable 40 and an electric chain hoist operation switch 36, and the clamshell bucket 31 Clamshell bucket switching valve 52 via Clamshell bucket opening / closing switch 53 It was decided that it would be operated using [this method].

[0065] As an alternative embodiment, as shown in Figure 7, the clamshell bucket 31 may be connected to a hydraulic pump 33 that operates the propulsion jack 3 installed on the open shield machine 1, and the clamshell bucket 31 may be operated by the oil supplied from the hydraulic pump 33.

[0066] Clamshell Bucket 31 Hydraulic pump It is connected to 33 via a clamshell bucket switching valve 52.

[0067] In the diagram, 53 is the clamshell bucket opening / closing switch, located between the distribution panel 55 from the generator 56 and the clamshell bucket switching valve 52. In the diagram, 54 shows the control panel for the propulsion jack 3.

[0068] Next, the open shield construction method using the open shield machine 1 described above. Concrete box The method for laying a 4- or U-shaped open channel 42 will be described below.

[0069] First, as shown in Figures 2, 4, and 5, the method for excavating and removing soil with the open shield machine 1 involves extending the propulsion jacks 3 equipped on the open shield machine 1 into the pre-laid U-shaped open channel 42 immediately behind it, while taking propulsion reaction force, thereby propelling the open shield machine 1 forward. Then, excavation is performed simultaneously with or, depending on the excavation shape of the face of the mountain and the soil properties, with the propulsion of the open shield machine stopped.

[0070] During excavation, the excavation clamshell bucket 31, suspended from the electric chain block hook 29 of the electric chain block 28 installed on the frame 27, is moved to a predetermined position on the excavation face in front of the cutting edge 2 of the front machine 17 of the open shield machine 1, while operating the electric chain block operation switch 36.

[0071] Then, by operating the electric chain hoist operation switch 36, the suspended bucket 31 is lowered to the face of the excavation site, the clamshell bucket 31 is opened and driven into the soil of the excavation site by its own weight, and excavation is performed. Then the bucket 31 is closed to grip the soil.

[0072] Subsequently, the bucket 31 is moved to the position of the excavated soil removal bucket 44, which has been transported to the rear of the tail machine 18 of the open shield machine 1. The bucket 31 is then suspended, and the excavated soil is loaded into the excavated soil removal bucket 44, which is placed on the transport trolley 46.

[0073] The transport equipment for the excavated soil removal bucket 44 consists of a transport trolley 46 and a battery-powered locomotive, which travels along the running rails 45 laid on the bottom slab of the U-shaped open channel 42 to the launch shaft 8.

[0074] The excavated soil is then lifted to the ground using the lifting and hoisting equipment 24 located on the launching shaft 8, and transported off-site by a dump truck 7.

[0075] The concrete box structure 4 or U-shaped open channel 42 is laid by excavating for the length of one U-shaped open channel (or the length of one box structure) with the open shield machine 1, as shown in Figures 3 and 6, and then fixing or temporarily placing it on the front machine 17 of the open shield machine 1, or as shown in Figure 6. Clamshell bucket Unit 31 is transported to the launch shaft 8 or temporary storage space using a transport system consisting of a transport trolley 46 and a battery locomotive, and then temporarily stored there.

[0076] Subsequently, the U-shaped open channel 42 is lowered to the bottom of the shaft by the lifting and lowering equipment 24 located on the launch shaft 8, and then transported to the rear of the tail section 18 of the open shield machine 1 by the transport equipment consisting of a transport trolley 46 and a battery locomotive.

[0077] Then, the U-shaped open channel 42 is lifted using the electric chain hoist 28 attached to the frame 27 and lowered and installed in the tail section 19 inside the tail machine 18.

[0078] While repeating the methods described above, the open shield machine 1 is advanced, and the U-shaped open channel 42 or concrete box structure 4 is laid. [Explanation of symbols]

[0079] 1…Open shield aircraft 1a...Side wall plate 1b...Bottom plate 2…Blade opening 3…Propulsion jack (shield jack) 4...Concrete box structure 5...Backfill 6…Excavator 7…Dump truck for removing excavated soil 8…Launch shaft 9…Reaction wall 11…Ground improvement 13…Achievement pit 15…Dump truck for backfilling 16...Slide jack 16a...Slide retaining plate 16b...Maximum extended sliding retaining plate 17...Front unit 18...Tail unit 19...Tail section 20...Folding jack 21... Backfill injection plant 22... Grout piping 23... Press bar (press angle) 24… Lifting and lowering equipment (rough terrain crane) 25...Backfill injection material 26...Cover plate 27... Framing 28... Electric chain hoist 29...Electric chain hoist hook 30...Beam material in the front-to-back direction 31…Clamshell bucket (hydraulic opening and closing type) 32... Generator 33... Hydraulic pump 36… Electric chain hoist operating switch 38... Signal wire 39... Hydraulic hose 40…Power cable 41...Beam for running 42...U-shaped open channel (concrete) 43...Battery-powered locomotive 44...Bucket for removing excavated soil 45... Running rails 46... Transport cart 47...Middle bend section 48...Rear retaining plate 49…Retaining wall 50…Existing fence culvert 51…Motor for movement 52... Clamshell bucket switching valve 53... Clamshell bucket opening / closing switch 54...Control panel 55...Distribution board 56... Generator

Claims

1. An open shield machine comprising a body consisting of left and right side wall plates and a bottom plate, divided in the front-rear direction into a front machine and a tail machine, the front end of the tail machine being fitted into the rear end of the front machine to make it bendable, and propulsion jacks being arranged on the front side of the inside of the tail machine, facing rearward, to the left and right and arranged in multiple vertical stages, wherein a frame with beam members in the front-rear direction is formed extending upward from the upper end of the tail machine, a traveling beam member on which a lifting and lowering equipment consisting of an electric chain block and an electric chain block hook is installed to be movable is horizontally mounted on the front-rear beam member, a clamshell bucket is suspended from the electric chain block hook of the lifting and lowering equipment, a sliding earth retaining plate is provided at the cutting edge of the front machine, and the front end of the front-rear beam member extends forward beyond the tip of the sliding earth retaining plate which extends to its maximum extent from the front end of the cutting edge of the front machine.

2. The open shield machine according to Claim 1, wherein the clamshell bucket is hydraulically operated, and the propulsion jacks installed on the open shield machine and the clamshell bucket are connected to separate hydraulic pumps mounted on the rear of the front of the open shield machine, and the propulsion of the open shield machine by extending the propulsion jacks and the opening and closing of the clamshell bucket can be operated simultaneously or individually while constantly checking the condition of the face of the tunnel.

3. The clamshell bucket is hydraulically operated, and the clamshell bucket is connected to a hydraulic pump that operates a propulsion jack installed on the open shield machine, and the clamshell bucket can be operated by oil supplied from the hydraulic pump, either by opening and closing the clamshell bucket using a clamshell bucket opening / closing switch connected to a generator by a power cable, or by opening and closing the clamshell bucket using a hydraulic pump, via a clamshell bucket switching valve.

4. A step of extending the sliding earth retaining plate to its maximum extent forward from the cutting edge of the front machine of the open shield machine, The excavation and soil transport / removal process involves suspending a clamshell bucket from a lifting and lowering device installed on a traveling beam of a frame structure with beams in the front-rear direction, moving it to the tip of the fully extended sliding earth retaining plate, moving the clamshell bucket beyond the tip of the fully extended sliding earth retaining plate to excavate a concave slope towards the front machine on the excavation face in front of the front machine, and then moving it to the soil transport equipment located at the rear for loading. The propulsion process of the open shield machine involves the extension of the propulsion jacks, An open shield construction method characterized by installing a concrete box body or U-shaped open channel by repeatedly performing the following steps: after pushing through the length of one box body, removing and moving the clamshell bucket, and lifting, moving, and lowering the concrete box body or U-shaped open channel, which has been transported to the rear of the open shield machine, into the tail machine.

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