JP6218180B2 - Rectangular section propulsion method - Google Patents

Description

  The present invention relates to a construction method for constructing a tunnel having a rectangular cross section.

  The current rectangular underground space construction method is as follows: (1) The method of constructing the outer retaining wall by the pipe roof construction method with a circular steel pipe first, and then excavating the outer wall after retaining the outer wall ( For example, refer to Patent Document 1), and (2) R & C method using a square steel pipe (replacement of concrete frame after box-type roof advanced excavation with spot cast concrete or concrete secondary product) (for example, refer to Patent Document 2), Harmonica construction method (in-place cast concrete is cast inside with an outer square steel pipe as an outer mold) (see, for example, Patent Document 3) and HEP & JES construction method (square steel pipes are arranged on the outer shell and connected with joints to connect the body structure (For example, refer to Patent Document 4). In addition, there is (3) a shield construction method (see, for example, Patent Document 5) in which a rectangular segment is assembled on the rear side of a free-cutting machine or the like. However, every construction method requires a long process, and the construction method prior to the outline excluding the shield construction method is centered on the two-step method, and there is a possibility that stress release of the ground will occur twice. In addition, the shield method takes time to manufacture the excavator, enormously costs the production of the excavator, and if the excavation extension is short, it is a great economic disadvantage.

<Open-cut tunneling method>
In order to perform excavation, it is necessary to construct earth retaining works on both sides in advance. As a kind of earth retaining work, there is a drilling type such as a continuous wall from the ground surface and a continuous column pile. The other is a method of driving steel sheet piles to the left and right, as in the steel sheet pile earth retaining method, and then excavating with an excavator and backfilling after burying the box to construct the tunnel.
・ Direct and indirect influences (vibration, noise, adjacent structures, underground structures, etc.) on the surrounding environment are large, and there are many problems for local residents due to traffic environment obstruction. Adequate construction yard is secured.
・ The construction cost has the most advantage.
・ In the deepest excavation part, the ground is opened, and there is a high possibility that the structure itself will sink, the ground will sink due to backfilling, the structure will become unevenly subsided, and the joint joints and box concrete joints will leak. .

<Free section shield method>
There are various structures for the shield machine. A load header method, a circular / drum combination method, a swing drum cutter method, an eccentric multi-axis method (DPLEX method), a method of adding an auger excavation function at an unexcavated corner, and the like are conceivable. Basically, shield machines are treated as total losses, and construction costs are recorded, so construction costs rise.
-Shield excavation machines are very expensive, so economic efficiency is a big problem.
・ A construction yard is required very large.
・ Because it will be completed by primary lining, construction will be possible for a short period from the start to the end of construction, but it will take at least 10 months to make the excavator.
-It is unsuitable for construction at short distances from the viewpoint of economy, and generally, the construction scale of 500 m or more is the condition for adopting the rectangular shield construction method.

<Pipe roof construction method>
In underground redevelopment in urban areas, it is difficult to plan in advance due to the large number of obstacles to burial (determining the section after underground burial survey, etc.). Pipe roof construction is often used to build underground spaces. Generally, round steel pipes are used (in some cases, square steel pipes may be used), and the steel pipes are preliminarily received in advance by a propulsion method. Connect using a steel pipe joint such as a joint. The construction procedure is to construct a start shaft and a reach shaft in advance, then horizontally receive the steel pipe tip with the pipe roof method, and after the horizontal earth retaining work is completed, the internal excavation and the steel support work are performed simultaneously. I do. When excavation and internal support work are completed, rebar placement and formwork are applied inside, and concrete is wound up. There are basically the following features.
・ Because the construction is for each span of the steel pipe, it is advantageous in that it does not excavate a large section at a stretch, and there is little influence on the ground during pipe roof construction.
・ It takes a long period of time to construct one by one.
-Since the horizontal retaining tip receiving steel pipe is left in the ground and the interior is filled, in the future it will be very advantageous for the stability of the internal structure.
-Economically, steel pipes are left behind and construction costs are high.
・ It is the most suitable method for construction of arbitrary cross sections (rectangles and some widened cross sections) and cross-section changes in the middle.
・ General construction extension is considered to be within 100m.
・ The biggest problem is that after pipe roof work is completed, internal excavation and internal support work will be installed, but at that stage, the steel pipe will bend in the longitudinal direction, and land subsidence will occur more easily.

<All-section ground improvement method (open type or blade edge propulsion type)>
In order to improve the strength of the ground and ensure excavation after ensuring the independence and water-stopping of the ground, in order to prevent the intrusion of groundwater during excavation, the ground will be improved by chemical injection and high-pressure injection methods.
・ Construction from the ground surface is the center, and the occupation of roads is likely to be a problem.
・ Drilling water during construction and agitated sludge are ejected to the ground surface, so these treatments are necessary.
・ Groundwater contamination will occur after construction.
・ Construction from the ground surface is the principle, but measures for horizontal injection and horizontal agitation are also required.
-A thorough investigation of the existing buried objects is necessary.
・ There is a high possibility that the existing underground objects will be affected during the injection.
-If the injection pressure is high, ground uplift will occur, and if the porosity is large, chemicals and cement runaway will occur, which may affect a wide area.

<Box roof method, HEP & JES method, R & C method, etc.>
The construction method that pulls in the earth before leading the outer shell, pulls in the rectangular concrete, the pressing method that pushes in, the construction method that uses the outer shell as the outer formwork to build the interior, and the square member of the outer shell that was buried in advance. There is a construction method used for part of the body structure.

JP 2005-16141 A JP 2001-73670 A JP 2004-250957 A JP 2000-120372 A Japanese Unexamined Patent Publication No. 2000-8781

  The problem to be solved by the present invention is that the conventional underpass construction method requires a large construction yard at the time of earth retaining construction, so these problems are solved and compared with the above-mentioned various construction methods. It is an object of the present invention to provide a construction method of a rectangular box with a large cross section that enables compact equipment and construction with high economic evaluation in a short period of time, and that has less land subsidence and soil contamination after construction.

The configuration of the present invention that solves this problem is as follows.
1) For excavation of the upper section of the rectangular box to be built underground, a plurality of circular or rectangular closed upper excavators are used, and for excavation of the lower section of the rectangular box, rectangular excavation is used. In addition, the rectangular excavator can be rotated around the discharge port, a discharge port that takes in the excavation soil, a soil removal device that transports the excavation soil taken from the discharge port to the rear, and discharges it. A rotary excavator, a rotary cutter that pivotally supports the rotary body and rotates and revolves by the rotation of the rotary body, and a drive unit that drives the rotation of the rotary body and the rotation of the rotary cutter. Side cutting parts for cutting the ground on both sides are provided on the left and right bulkheads of both sides of the machine , and these excavators are integrated with a rectangular shell with a bulkhead with a bulkhead, and the upper excavator is a jack installed inside the inner shell. With the ability to move back and forth Each upper excavator is equipped with an independent earth removal device that takes the excavated sediment and discharges it backwards, a cutting bit that reduces penetration resistance is provided at the tip of the comprehensive trunk pipe, and multiple upper excavators are one by one with a jack After excavating the upper part of the ground while making it move forward and making the earth load on the earth covering in a pre-received state with all of the upper excavators that have advanced, the main pusher that installed the comprehensive trunk pipe integrated with the rectangular excavator in the start shaft While excavating the lower part of the ground with a rectangular excavator while moving forward with the device, the upper excavator is housed in the comprehensive trunk pipe while shrinking the jack, and the upper and lower excavations are repeated alternately and the comprehensive trunk pipe The rectangular section propulsion method is characterized in that the rectangular concrete is constructed by burying the boxed concrete that follows the ground 2) The muddy water injection hole in which the partition wall injects high-pressure muddy water into the excavation part of the ground Has Than is the 1) rectangular section jacking method 3) box body concrete impossible transported in integral described, performs integral assembly by connecting the pieces which are divided into a plurality of two-division or three-division in situ The rectangular cross-section propulsion method described in 1) or 2), which can be constructed by the propulsion method, and 4) provided with an agitating and mixing cutter for agitating and mixing the ground in the unexcavated portion at the middle position between the left and right upper excavators In the rectangular cross-section propulsion method described in any one of 1) to 3) above.

  According to the present invention, since the construction is carried out by combining the upper and lower excavators, it is possible to divide the rectangular section, excel in the stability of the ground, and no need for auxiliary construction methods such as earth retaining work for the outer shell, The construction yard is also small compared to other construction methods, and a rectangular box with a large cross section can be constructed in a short period of time. Moreover, there is no excavation or backfilling work, and ground improvement such as chemical solution injection is basically not necessary for the entire cross section only near the wellhead, so that ground subsidence and soil contamination are reduced.

It is a front view of the upper excavation machine and rectangular excavation machine of an Example. It is sectional drawing of the upper excavation machine and rectangular excavation machine of an Example. It is explanatory drawing which shows the excavation range of the rotary cutter of an Example. It is explanatory drawing which shows the process of the rectangular cross-section promotion construction method of an Example. It is explanatory drawing which shows the process of the rectangular cross-section promotion construction method of an Example. It is a front view of the upper excavator and the rectangular excavator of another example of the embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes for carrying out the present invention will be specifically described with reference to typical examples and drawings. In addition, this invention is not limited to a following example, Various combinations and deformation | transformation are possible. For example, it is also possible to construct a rectangular box with a larger cross section by setting the rectangular excavator to the left and right duplex and the upper excavator to the left and right triple or quadruple.

  This embodiment is shown in FIGS. In the figure, 1 is a rectangular excavator, 2A and 2B are upper excavators, 3 is a comprehensive trunk pipe, 4 is box concrete, G is the ground, and S is a drilling hole.

  The rectangular excavator 1 is configured to be capable of rotating around a discharge port 11 for discharging excavated soil, a soil discharger 12 for transporting and discharging the excavated soil taken from the discharge port 11 backward, and a discharge port 11. A rotary body 13 provided; three rotary cutters 14 that pivotally support the rotary body 13 and rotate and revolve with the rotation of the rotary body 13; and a drive unit 15 that drives the rotation of the rotary body 13 and the rotation of the rotary cutter 14. It consists of

  The earth removal device 12 includes an earth removal pipe 12a that serves as a passage for excavation earth and sand, a screw conveyor 12b that conveys the earth excavation soil in the earth discharge pipe 12a, a motor 12c that drives the screw conveyor 12b, and excavation earth and sand that are being conveyed. The soil discharge valve 12d that can be expanded and contracted to adjust the amount of soil discharged, and the openable and closable soil discharge gate 12e that discharges the excavated soil that has been conveyed to the outside.

  The rotary cutter 14 is an eccentric type, and is provided at a position where the rotation shaft is eccentric from the center portion. When the drive unit 15 revolves up, down, left, and right positions as shown in FIG. When rotating at the four corner positions, the rotation is performed so that the length is on the outside. As a result, the ground G can be excavated into a rectangular cross section. The left and right portions where the rotary cutter 14 does not reach are cut by a side cutting portion 36 described later.

  The upper excavator 2A, 2B includes an exterior 21, a partition wall 22 having a discharge port 22a for taking in the excavated soil, and a soil removal device 23 for transporting and discharging the excavated soil taken in from the soil outlet 22a to the rear. The rotary cutter 24 is pivotally supported by the central portion of the partition wall 22, the drive unit 25 drives the rotary cutter 24, and the press ring 26 receives the propulsive force of the upper excavator push-in jack 38 described later. .

  The exterior 21 has a cylindrical shape with a length of about 4 m, a backing stopper 21a and a sliding stopper 21b that regulate the sliding amount of the upper excavators 2A and 2B, and a double packing with a brush that prevents the inflow of excavated earth and sand. 21c. The earth removal device 23 includes an earth removal pipe 23a serving as a passage for excavated earth and sand, and an expandable / contractable earth discharge valve 23b that adjusts the amount of earth excavated during the conveyance.

  For example, the inclusion tube 3 has a rectangular section having a height of about 6.2 m and a width of about 5 m, and includes muddy water injection holes 31 a and 32 a for injecting high-pressure muddy water. , 2B are slidably supported by two guide cylindrical sleeves 33, a direction correcting jack and an intermediate pushing jack 34 for correcting the digging direction, and a cutting bit 35 and a side cutting part 36 for cutting the ground G into a rectangular cross section. It is configured. The backing stopper jig 21a and the slide stopper jig 21b of the upper digging machines 2A and 2B come into contact with the front and rear ends of the guide cylindrical sleeve tube 33 so that the sliding amount of the upper digging machines 2A and 2B is regulated to 1.8 m. It has become. Further, the double packing 21c with the brushes of the upper digging machines 2A and 2B is brought into close contact with the inner peripheral surface of the guide cylindrical sleeve tube 33 so that the inflow of excavated soil and mud water into the inclusion tube 3 is prevented. Yes. The side cutting part 36 cuts the left and right parts that have not been excavated by the rectangular excavator 1 with the driving force of the original push.

  The rectangular excavator 1 is installed in the lower part of the inclusion tube 3, a mud storage tank 37 for storing mud sediment is installed at the rear position thereof, and a sediment delivery device 37 a for sending the excavated sediment to the mud tank 37 is provided. Installed at a position directly below the earth removing device 12. The upper digging machines 2A and 2B are respectively inserted into the two guide cylindrical sleeves 33, and the two upper digging machine push-in jacks 38 for pushing the left and right push wheels 26 are attached to the rear part of the inclusion tube 3, respectively. The soil discharge pipe 23a and the mud storage tank 37 are connected to each other by a soil discharge hose 37b that can be expanded and contracted. A stirring / mixing cutter 39 that stirs and mixes natural ground is provided at an intermediate position (unexcavated portion) between the left and right upper excavators 2A and 2B. Each of the above equipment is a size that can be transported on the road and assembled on site.

  The box concrete 4 has a rectangular cross section with a height of 6.1 m and a width of 4.9 m, for example, and is manufactured in a state of being divided into pieces each having a size that can be transported on the road. It can be assembled to ensure waterproofness.

  In this embodiment, as shown in FIG. 4 (a), a plurality of box concrete 4 is connected to the rear end of the envelope tube 3, and the tail box box concrete 4 is used as a main pushing device ( (Not shown). In this state, muddy water is injected from the muddy water injection hole 32a and either the left or right upper digging machine 2A or 2B (in this embodiment, the left upper digging machine 2A) is operated, as shown in FIG. 4 (b). The upper part of the ground G is excavated into a circular cross section while being advanced with respect to the rectangular excavator 1 by the upper excavator pushing jack 38. In the upper excavator push-in jack 38, the rod 38a abuts on the rear end of the envelope tube 3 to obtain a reaction force, and pushes the push ring 26 forward to advance. The excavated soil is fluidized with muddy water, taken in from the earth discharge port 22a, and sent to the mud storage tank 37 through the earth discharge pipe 23a and the earth discharge hose 37b with earth pressure. During this time, the inclusion tube 3 and the box concrete 4 are stationary.

  When the slide stop jig 21b of the left upper digging machine 2A comes into contact with the rear end of the guide cylindrical sleeve tube 33, as shown in FIG. 5 (a), the right upper digging machine 2B is operated to The upper part of the ground G is excavated into a circular cross section while being advanced with respect to the rectangular excavator 1 by the excavator pushing jack 38. As with the left side, the excavated soil is fluidized with muddy water and fed into the mud storage tank 37, and is stopped when the slide stop jig 21b contacts the rear end of the guide cylindrical sleeve tube 33. As a result, the upper part of the ground G is excavated in advance, and the left and right upper excavating machines 2A and 2B have advanced to receive the total earth pressure (earth load) on the earth covering. By this advance excavation, it is possible to minimize the loosening of the ground G as compared with the case of excavating the entire cross section at once.

  Next, the muddy water is injected from the muddy water injection hole 31a and the rectangular excavator 1 is operated, and as shown in FIG. The lower part of the ground G is excavated into a rectangular cross section. The left and right upper digging machine push-in jacks 38 are contracted in parallel, and the left and right upper digging machines 2A and 2B return to the guide cylindrical sleeve tube 33 in a fixed position by contact with the ground G. At this time, since the excavation of the upper part has already been completed, the load of the front resistance and the upper load is reduced as compared with the case where the entire cross section is excavated at one time, and the penetration resistance of the comprehensive trunk pipe 3 is also reduced by the injection of muddy water. To do. The excavated earth and sand is taken into the earth discharge port 11 and conveyed backward by the screw conveyor 12b, falls from the earth discharge gate 12e, and is sent out to the mud storage tank 37 by the earth and sand delivery device 37a. Unexcavated portions that have not been excavated by the rectangular excavator 1 and the upper excavators 2A and 2B are cut by the cutting bit 35 and the side cutting portion 36. When the backing stoppers 21a of the left and right upper excavators 2A and 2B come into contact with the front end of the guide cylindrical sleeve tube 33 and are accommodated in the guide cylindrical sleeve tube 33, the rectangular excavator 1 and the main push are stopped.

  As described above, the upper excavation by the left and right upper excavators 2A and 2B and the lower excavation by the rectangular excavator 1 are shown in FIGS. 4 (a), 4 (b) and 5 (a), (b). The ground G is dug into a rectangular cross section, and a rectangular box is built in the ground.

  FIG. 6 shows another example of this embodiment. In this example, rectangular upper digging machines 2A and 2B are used instead of the circular upper digging machines 2A and 2B. This reduces the gap between the left and right upper excavators 2A and 2B due to the square shape, and reduces the number of unexcavated portions compared to a circular shape, thus more reliably receiving the top sediment. Looseness can be prevented. In addition, since the upper part of the ground G is also excavated into a rectangular cross section, the penetration resistance of the covering trunk tube 3 is further reduced. In other respects, the reference numeral, the configuration, and the operational effects are the same as in the embodiment.

  The technology of the present invention is useful for the construction of underground passages, rainwater troughs, common ditches, etc., whose internal cross section exceeds 3.0 m.

DESCRIPTION OF SYMBOLS 1 Rectangular excavation machine 11 Earth discharge port 12 Earth removal apparatus 12a Earth removal pipe 12b Screw conveyor 12c Motor 12d Earth removal valve 12e Earth removal gate 13 Rotating body 14 Rotary cutter 15 Driving part 2A Upper machine 21B Exterior machine 21a Backing stop Jig 21b Slide stop jig 21c Double packing with brush 22 Bulkhead 22a Soil outlet 23 Soil discharger 23a Soilpipe 23b Soil discharge valve 24 Rotating cutter 25 Drive part 26 Push ring 3 Comprehensive trunk pipe 31 Bulkhead 31a Mud spray hole 32 Bulkhead 32a Mud spray hole 33 Guide cylindrical sleeve 34 Direction correction jack and intermediate push jack 35 Cutting bit 36 Side cutting part 37 Mud storage tank 37a Sediment delivery device 37b Soil discharge hose 38 Upper excavator push jack 38a Rod 39 Stir mixing cutter 4 Box concrete G Ground S drilling

Claims (4)

For excavation of the upper section of the rectangular box to be built in the ground, a plurality of circular or rectangular sealed upper excavators are used, and for excavation of the lower section of the rectangular box, the rectangular excavator is used. In addition, the rectangular excavator is provided with a discharge port for taking in the excavated sediment, a soil removal device for conveying the excavated soil taken from the discharge port to the rear and discharging it, and a rotation around the discharge port. The rotating body, a rotating cutter that pivotally supports the rotating body and rotates and revolves by the rotation of the rotating body, and a drive unit that drives the rotation of the rotating body and the rotation of the rotating cutter. Side cutting parts for cutting the ground on both sides are provided on the right and left bulkheads of the two, and these excavators are integrated with a rectangular cross section of the general-purpose cylinder pipe with a bulkhead, and the upper excavator is a jack installed inside the internal cylinder pipe and its a function capable of moving back and forth and forward, the upper The soil discharge device independent for discharging rearwardly captures excavated soil at excavator provided, inclusive cylinder tube distal cutting bit to reduce the penetration resistance provided of advancing a plurality of upper tunneling machine by one body by a jack While excavating the upper part of the ground and making the earth load on the earth covering in a pre-received state with all the upper excavators that have advanced, the main pusher installed a comprehensive trunk pipe integrated with the rectangular excavator in the start shaft While excavating the lower part of the ground with a rectangular excavator while moving forward, the upper excavator is housed in the comprehensive barrel pipe while contracting the jack, and the upper and lower excavations are alternately repeated to follow the comprehensive trunk pipe A rectangular cross-section propulsion method characterized in that a rectangular box is constructed by burying the boxed concrete in the ground. The rectangular cross-section propulsion method according to claim 1 , wherein the partition wall is provided with a muddy water injection hole for injecting high-pressure muddy water into the excavation portion of the ground . The box concrete, which cannot be transported as a single piece, is made by connecting the pieces divided into two or three into a plurality of pieces on the site and assembling them together to enable construction by the propulsion method. Or the rectangular cross-section propulsion method of 2 description. The rectangular cross-section propulsion method according to any one of claims 1 to 3, wherein a stirring and mixing cutter that stirs and mixes natural ground in an unexcavated portion at an intermediate position between the left and right upper excavators .

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