JP2023068271A - Construction method of steel shell element - Google Patents

Abstract

To provide a construction method with a reduced construction period and cost through labor saving of work.SOLUTION: A construction method includes steps of inserting an adjacent steel shell element 3 to a steel shell element 2 to be inserted previously in a state in which a temporary steel pipe 6 is attached on the inserted steel shell element 2 after the temporary steel pipe 6 is attached thereon to enlarge a section to the adjacent steel shell element 3 side; and pulling the temporary steel pipe 6 after installation of the steel shell element 3. Surplus soil to be reduced after insertion installation of the steel shell element 3 is allowed to be reduced, because the surplus soil remaining between side plates of the previously inserted steel shell element 2 and the post inserted steel shell element 3 is reduced only by the amount equal to an area of an enlarged section through installation of the temporary steel pipe 6.SELECTED DRAWING: Figure 5

Description

According to the present invention, a steel shell element having a rectangular hollow cross section is sequentially inserted into the ground while connecting the steel shell element and the joint part that have already been penetrated, and the outer shell structure having a closed cross section by the steel shell element is repeated in the ground. This relates to a method for constructing a steel shell element for constructing a tunnel having a constant cross-sectional area in the direction of the tunnel in the outer shell precedent tunnel constructed by removing the internal earth and sand of the outer shell structure after constructing.

Conventionally, as one of the construction methods for constructing a grade-crossing tunnel under a road line or a railway line, a special joint is used, and square steel shell elements divided into about 1 m are connected while connecting the joint. Continuing to install in the ground, fill the steel shell elements with concrete, build an outer shell structure using it as a member, and then excavate and remove the earth and sand inside the outer shell structure. A non-excavation method for completing tunnels has been put into practical use.

The applicant of the present application also discloses in Patent Document 1 below that in a steel shell element joint structure for constructing an underground structure by successively penetrating the steel shell elements while connecting with the steel shell elements that have already been penetrated, the water stop portion We proposed a new joint structure with

JP 2015-71904 A

As disclosed in the above-mentioned Patent Document 1, the construction of the conventional steel shell element is performed, as shown in FIG. An opening 52 is provided at a predetermined interval along the axial direction of the element for removing the earth and sand remaining between the side plates 51, 51 of the element, and a closing plate 53 for closing the opening 52 is provided. As shown in FIG. 10, while fitting the convex joint 55 to the concave joint 54 of the steel shell element 50 that has penetrated earlier, the following steel shell element 50 is penetrated, and then the steel shell element 50 is shown in FIG. As described above, the earth and sand remaining between the side plate 51 of the preceding steel shell element 50 and the side plate 51 of the following steel shell element 50 is removed by removing the closing plate 53 that blocks the opening 52 provided in the side plate 51, The procedure was to remove from the opening 52 .

In this way, in the conventional construction, the surplus soil between the side plates of the preceding steel shell element and the following steel shell element must be manually excavated and removed in a narrow tunnel. This resulted in a prolonged period of time and an increase in costs.

SUMMARY OF THE INVENTION Accordingly, the main object of the present invention is to provide a method for constructing a steel shell element that saves labor and reduces construction period and cost.

In order to solve the above problem, as the present invention according to claim 1, the steel shell element having a rectangular hollow cross section is repeatedly penetrated into the ground while connecting the steel shell element and the joint part that have been penetrated one by one. A method for constructing the steel shell element when constructing an outer shell precedent tunnel by constructing an outer shell structure having a closed cross section using the steel shell elements, and then removing soil and sand inside the outer shell structure, the method comprising:
A temporary steel pipe that expands the cross section to the adjacent steel shell element side is attached to the steel shell element that is penetrated first,
A steel shell element characterized by penetrating the steel shell element in the next order in a state in which the temporary steel pipe is attached to the steel shell element that has already been penetrated, and pulling out the temporary steel pipe after the construction of this steel shell element is completed. A construction method is provided.

In the invention according to claim 1, the steel shell element to be penetrated first is attached with a temporary steel pipe that expands the cross section toward the adjacent steel shell element, and the temporary steel pipe is attached to the steel shell element that has already been penetrated. Then, adjacent steel shell elements are penetrated while connecting the joint portions, and after the construction of the subsequent steel shell elements is completed, the temporary steel pipe is pulled out. As a result, the amount of surplus soil accumulated between the side plates of the previously penetrated steel shell element and the next steel shell element is reduced by the amount of the cross section enlarged by arranging the temporary steel pipe, and the steel shell element The amount of surplus soil to be excavated and removed after installation of the intrusion is reduced. Therefore, it is possible to save labor in the work and reduce the construction period and cost.

As the present invention according to claim 2, each of the steel shell elements has a basic cross-sectional dimension defined by a maximum width dimension and a maximum height dimension of a shape obtained by combining a rectangular hollow cross section and the temporary steel pipe in the tunnel direction. A method for constructing a steel shell element according to claim 1 is provided.

In the second aspect of the invention, since the cross-sectional shape of each steel shell element should basically match the excavation cross-sectional shape of the excavator, the basic cross-sectional dimension of each steel shell element is constant in the tunnel direction. .

As the present invention according to claim 3, the temporary steel pipe is arranged so that the cross section expands to a range that substantially coincides with the tip part of the joint part projecting to the side of the adjacent steel shell element. There is provided a method of constructing a steel shell element as described above.

In the invention according to claim 3, the temporary steel pipe is arranged so that the cross section expands to a range that substantially coincides with the tip end portion of the joint portion projecting to the side of the adjacent steel shell element, thereby allowing the steel shell element to penetrate. In some cases, it is sufficient to excavate a substantially rectangular cross section, which simplifies the excavator and improves versatility.

As the present invention according to claim 4, the steel shell element construction according to any one of claims 1 to 3, wherein the temporary steel pipe is fixed to the steel shell element with a bolt, and can be pulled out by removing the bolt. A method is provided.

In the invention according to claim 4, the temporary steel pipe is fixed to the steel shell element by a bolt, and the temporary steel pipe can be pulled out by removing the bolt. Together with this, it can be easily pulled out.

As the present invention according to claim 5, the step of penetrating while connecting the convex joint of the steel shell element in the next order to the concave joint of the steel shell element that has been penetrated. A method of constructing a steel shell element is provided.

In the invention according to claim 5, when the steel shell element is penetrated, the concave joint portion of the steel shell element is penetrated without connecting, and when the next steel shell element is penetrated, the concave joint of the steel shell element whose convex joint has already been installed is inserted. It is intrusively installed in a state where it is connected to According to this procedure, the penetration accuracy and efficiency of the steel shell element are improved, and at the same time, it becomes easier to secure water stoppage.

According to a sixth aspect of the present invention, the excavator used for penetrating the steel shell element has a shape of the front excavation portion that matches the shape of the square hollow cross section of the steel shell element and the temporary steel pipe. and an auxiliary cutter for excavating the earth and sand portion corresponding to the joint portion is provided in the body portion, or the excavator performs over excavation in a range including the joint portion A method of constructing the described steel shell element is provided.

In the invention according to claim 6, the excavator used for penetrating the steel shell element has a shape of the front excavation portion that matches the shape of the combination of the square hollow cross section of the steel shell element and the temporary steel pipe. In addition, since the body is equipped with an auxiliary cutter for excavating the earth and sand portion corresponding to the joint portion, or the excavator is used to excavate the range that includes the joint portion, excavation It becomes easier to penetrate the steel shell element into the excavated part by machine.

As described in detail above, according to the present invention, it is possible to provide a method of constructing a steel shell element that can save labor and reduce the construction period and cost.

1 is a cross-sectional view of a shell structure 1 constructed according to the invention; FIG. FIG. 4 is a perspective view showing a procedure (part 1) for constructing the outer shell structure 1; FIG. 10 is a perspective view showing a procedure (part 2) for constructing the outer shell structure 1; FIG. 11 is a perspective view showing a construction procedure (part 3) of the outer shell structure 1; FIG. 11 is a perspective view showing a construction procedure (part 4) of the outer shell structure 1; It is a sectional view showing an excavation range. 1 is a front view of an excavator 20; FIG. 2 is a longitudinal sectional view of the drilling rig 20. FIG. FIG. 5 is a cross-sectional view showing a conventional steel shell element 50; FIG. 10 is a cross-sectional view showing a procedure (part 1) for constructing a conventional steel shell element 50; FIG. 10 is a cross-sectional view showing a procedure (part 2) for constructing a conventional steel shell element 50;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In the present invention, as shown in FIGS. 1 and 2 to 5, the procedure of inserting steel shell elements 3 having square hollow cross sections sequentially while connecting the steel shell elements 2 that have already been penetrated and joint portions is repeated. After constructing an outer shell structure 1 closed in a shape such as a rectangle, a circle, or a polygon in a cross-sectional view by a large number of steel shell elements in the ground, the internal earth and sand of this outer shell structure 1 is removed. This is a construction method of the steel shell element when constructing the outer shell precedent tunnel by doing. In particular, the invention is a method of constructing a tunnel with a constant cross-sectional area in the direction of the tunnel.

Since the method for constructing tunnels in front of the outer shell has the advantage of having little impact on the surrounding ground, it is often used as a construction method for constructing underpass tunnels without excavation in the ground beneath roads, railways, etc. It is what is done.

In particular, in the present invention, a temporary steel pipe 6 is attached to the steel shell element 2 to be penetrated first, and the temporary steel pipe 6 is attached to the steel shell element 2 that has already been penetrated. In this state, the steel shell elements 3 adjacent to each other are penetrated, and after the construction of the steel shell elements 3 is completed, the temporary steel pipe 6 is pulled out, thereby saving labor in constructing the outer shell structure 1. It is. More specific details will be given below.

The steel shell elements are arranged in the intermediate portions of the starting element 2 to be penetrated first, the upper floor slab 1A, the lower floor slab 1B, and the side wall slabs 1C, 1C of the outer shell structure 1, depending on the difference in cross-sectional shape and penetration procedure. Categorized into four types of steel shell elements: standard elements 3, 3 . be done. In FIG. 1, the circled numbers inside the steel shell elements 2 to 5 indicate the order of penetration.

First, as shown in FIG. 2, the starting element 2 is basically an element having a rectangular hollow cross section composed of an upper plate 20, a lower plate 21 and side plates 22,22. On both sides of the upper plate 20 and the lower plate 21, projecting members 23, 23 extending outward from the side plate 22 and extending toward the adjacent steel shell element 3 are provided. , concave joints 24, 24 are provided along the longitudinal direction of the member. The extension length of the extension member 23 is substantially constant over the entire length.

Temporary steel pipes 6 are attached to both side plates 22, 22 of the starting element 2, respectively, to enlarge the cross section toward the adjacent steel shell element 3 side. The temporary steel pipe 6 is a steel pipe having a substantially rectangular cross section and extending in the tunnel direction, and is fixed to the outer surface of the side plate 22 by a plurality of bolts 7 .

In the starting element 2, the temporary steel pipes 6 are provided between overhang members 23, 23 extending to the sides of the upper plate 20 and the lower plate 21 and concave joints 24, 24 provided at the ends thereof. there is That is, the height dimension _H6 of the temporary steel pipe 6 is smaller than the height dimension H of the rectangular hollow section by the thickness of the concave joints 24,24. The temporary steel pipe 6 is formed with a constant cross-sectional shape in the tunnel direction.

A plurality of bolts 7 are used to fix the temporary steel pipe 6 to the starting element 2 . For fixing by the bolts 7, through holes are provided in the side plates 22 of the starting element 2, and through holes are provided in the corresponding positions of the temporary steel pipe 6, and nuts are fixed inside them. A bolt 7 is inserted through the through hole from the inside of the rectangular hollow section and screwed into the nut. As a result, after the starting element 2 has been penetrated and installed, an operator can enter the interior of the rectangular hollow section to remove the bolts 7 .

The starting element 2 has concave joints 24, 24... on both sides, and serves as a steel shell element that is first penetratingly installed in the ground. The excavator used for penetrating installation of the steel shell element 2 has a basic cross-sectional dimension defined by the maximum width dimension B and the maximum height dimension H of the shape obtained by combining the square hollow cross section and the temporary steel pipe 6. A matching cross-sectional excavator 40 is used.

Next, the standard element 3 arranged adjacent to one side of the starting element 2 is an element of rectangular hollow cross-section constituted by an upper plate 30, a lower plate 31 and side plates 32, 32, as shown in detail in FIG. is the basic form. On one side of the upper plate 30 and the lower plate 31 (on the side of the starting element 2), projecting members 33, 33 extending outward from the side plate 32 are provided. A convex joint 34 is provided at the end. On the opposite side of the convex joint 34, a protruding member 35 is provided in which the upper plate 30 and the lower plate 31 extend outward from the side plate 32. At the tip of the protruding member 35, a A concave joint 36 is provided. The extension length of the extension members 33 and 35 is substantially constant over the entire length.

The side plate 32 on the side of the standard element 3 on which the concave joint 36 is provided has a cross section that is enlarged toward the adjacent steel shell element (the next steel shell element that is connected and penetrated with respect to the standard element 3). A temporary steel pipe 6 is attached. On the other hand, the temporary steel pipe 6 is not provided on the side plate 32 on which the convex joint 34 is provided. The temporary steel pipe 6 has the same structure as that used in the starting element 2, so the description thereof is omitted.

As an excavator used for penetrating installation of the standard element 3, an excavator similar to the excavator 40 used for the starting element 2 can be used.

After some of the standard elements 3 are arranged adjacently (three in the illustrated example), the adjustment elements 4 are arranged adjacently. The adjustment element 4, representatively explained with element No. 5 in FIG. A projecting member extending outward from the side plate is provided on (the side of the standard element 3 arranged one before), and a convex joint is provided at the tip of this projecting member along the longitudinal direction of the member. In addition, on the lower side of both side plates (on the side of the next standard element 3), an overhanging member extending outward from the lower plate is provided, and a concave joint is provided at the tip of this overhanging member along the longitudinal direction of the member. ing. The extension length of the extension member is substantially constant over the entire length.

The lower plate of the adjustment element 4 on the side where the concave joint is provided has a cross section that is enlarged toward the adjacent steel shell element (the next steel shell element 3 that is connected to and penetrates the adjustment element 4). A temporary steel pipe 6 is attached. On the other hand, the temporary steel pipe 6 is not provided on the side plate on which the convex joint is provided. The temporary steel tube 6 is of similar construction to that used in the starting element 2 .

The closing element 5, which is inserted last, is basically an element with a square hollow cross-section consisting of an upper plate, a lower plate and a side plate. Each of them is provided with an overhang member extending outward from the side plate and extending toward the adjacent steel shell element 3, and a convex joint is provided at the tip of the overhang member along the longitudinal direction of the member. The extension length of the extension member is substantially constant over the entire length.

The steel shell element 5 is not provided with the temporary steel pipe 6 . That is, since the steel shell elements 3, 3 on both sides that have been penetrated first are provided with the temporary steel pipes 6 that expand the cross section toward the closing element 5 side that is penetrated last, the temporary steel pipes 6 are provided on the closing element 5. 6 need not be provided.

The temporary steel pipes 6 attached to the respective steel shell elements 2 to 4 are steel pipes extending in the axial direction of the outer shell structure 1 having a substantially rectangular cross section, and face the steel shell elements to be penetrated in order among the steel shell elements. It is fixed to the plate member by a plurality of bolts 7 . After penetrating and installing the steel shell element 2 provided with the temporary steel pipe 6, the following steel shell element 3 is penetrated while connecting the joint parts to the steel shell element 2 that has been penetrated, and the following steel shell element. When the installation of 3 is completed, the temporary steel pipe 6 attached to the previously penetrated steel shell element is pulled out after removing the bolts 7 .

In this way, since the temporary steel pipe 6 that expands the cross section toward the adjacent steel shell element 3 side is attached to the steel shell element 2 that is penetrated first, the expanded cross section is obtained by arranging the temporary steel pipe 6. Accordingly, the amount of surplus soil that accumulates between the side plates of the steel shell element 2 that penetrates first and the steel shell element 3 that follows is reduced, and the amount of surplus soil that must be excavated and removed after the steel shell element 3 has been penetrated and installed is reduced. do. As a result, the work can be labor-saving, and the construction period and cost can be reduced.

In addition, after the steel shell element 3 that follows is inserted and installed, the temporary steel pipe 6 attached to the steel shell element 2 that has been penetrated first is pulled out and removed. It does not adversely affect the fillability of the

The provisional steel pipe 6 is arranged in a range between concave joints 24, 24 or between concave joints 36, 36 arranged respectively on the inner peripheral side and the outer peripheral side when the outer shell structure 1 is constructed. The tip of the concave joint 24 provided at the tip of the projecting member 23 projecting from the outer surface of the plate member facing the shell element (the side plate 22 in the case of the starting element 2 shown in FIG. 2) to the side of the adjacent standard element 3. is a substantially rectangular range between Therefore, the cross-sectional shape of the steel shell element including the temporary steel pipe 6 is substantially rectangular except for the portion of the convex joint 34 that is inserted and connected to the previously penetrated concave joint 24 (see FIG. 6).

Next, while following the procedure for constructing the outer shell structure 1, the procedure for penetrating the steel shell elements 2 to 5 will be described in detail.

The procedure for penetrating the steel shell elements 2 to 5 is the order numbered No. 1 to No. 15 in the cross-sectional view of the shell structure 1 shown in FIG. That is, among the rectangular cross sections in which a large number of steel shell elements 2 to 5 are closed in a rectangular shape, the steel shell element 2 (No. 1: starting element) at the center of the upper floor slab 1A is first penetrated, 2 as a base point, the steel shell elements 3, 3, . The shell element 4 (No. 5: adjustment element) is penetrated, and the steel shell elements 3, 3 ... (standard elements) are sequentially penetrated downward to construct the side walls 1C, 1C, and then the lower end corners. Starting from the steel shell element 4 (No. 11: adjustment element), the steel shell elements 3, 3, . , an outer shell structure 1 is constructed in which a large number of steel shell elements 2 to 5 are closed in a rectangular shape when viewed in cross section.

A more detailed penetrating procedure will be explained based on FIGS. A starting element 2 with a temporary steel pipe 6 attached to each of the side plates 22, 22 is penetrated. An excavator 40 is used for the intrusive installation of the starting element 2 . The excavator pulls the starting element, or the pushing jack pushes the excavator and the starting element 2 while penetrating. As the excavator 40, for example, an excavator shown in FIGS. 7 and 8 can be used. The illustrated excavator 40 is a closed-type excavator, which enables construction of the outer shell structure 1 without ground improvement even below the ground water level. A main cutter 42 provided at the tip of an auger screw 41 and a predetermined number of planetary cutters 43, 43 are provided. , to excavate in a rectangular section. The soil discharge method is a screw conveyor method. Auxiliary cutters 44 for excavating earth and sand portions corresponding to the concave joints 24 are detachably attached to the four corners. When the starting element 2 is inserted, auxiliary cutters 44, 44 are provided at the four corner positions where the concave joints 24, 24, . Auxiliary cutters 44, 44 are provided at the upper and lower corner positions where the are provided. It should be noted that the excavator 40 may be used to excavate the area including the concave joint 36 without the auxiliary cutter 44 .

By equipping the steel shell elements 2 to 4 with the temporary steel pipes 6, it is possible to prevent the wall surface excavated by the excavator 40 from collapsing until the adjacent steel shell elements are penetrated.

Once the starting element 2 has been penetrated, as shown in FIG. While connecting the convex joint 34, the next adjacent standard element 3 (No. 2) is penetrated. When the penetration of this standard element 3 is completed, as shown in FIG. Some sand may remain.

Thereafter, as shown in FIG. 5, the temporary steel tube 6 attached to the previously penetrated starting element 2 is withdrawn. Before pulling out the temporary steel pipe 6, all the bolts 7, 7... for fixing to the start element 2 are removed.

After the temporary steel pipe 6 is pulled out, if necessary, the surplus soil accumulated between the temporary steel pipe 6 and the standard element 3 that has penetrated subsequently is removed. In order to remove this surplus soil, an opening (not shown) is provided in the side plate to which the temporary steel pipe 6 is attached, the cover covering this opening is removed, and the excavation is removed manually from the opening. With conventional steel shell elements, there is a large amount of surplus soil between the elements, so it is necessary to increase the size of the openings and reduce the pitch of the openings to make it easier to remove the surplus soil from the openings. However, in the steel shell element according to the present invention, the provision of the temporary steel pipe 6 significantly reduces the amount of surplus soil between the elements, so it is removed from the opening. The amount of residual soil is small, the size of the openings can be made small, and the formation pitch of the openings can be increased, ensuring the strength of the steel shell element. In addition, when the opening for removing the surplus soil is closed with the temporary steel pipe 6, it is not necessary to separately provide a lid for closing the opening.

[Other form examples]
(1) In the example above, the central part of the upper floor slab was used as a starting point, and it was constructed on both sides in order up to the central part of the lower floor slab on the opposite side. may be constructed.

(2) In the above embodiment, the following steel shell element 3 is inserted while the convex joint 34 is connected to the concave joint 24 of the steel shell element 2 that has already been penetrated. It is also possible to have a reverse relationship, that is, insert the following steel shell element 3 while connecting the concave joint to the convex joint of the steel shell element 2 that has already penetrated. As shown in this embodiment, the relationship between the convex joint and the concave joint is such that the following steel shell element 3 is connected while the convex joint 34 is connected to the concave joint 2 of the steel shell element 2 that has already penetrated. Penetration is preferable.

DESCRIPTION OF SYMBOLS 1... Shell structure, 2... Steel shell element (starting element), 3... Steel shell element (standard element), 4... Steel shell element (adjusting element), 5... Steel shell element (closing element), 6... Temporary Steel pipe 7 Bolt 24 36 Concave joint 34 Convex joint 40 Excavator

Claims (6)

After constructing an outer shell structure with a closed cross-section of the steel shell elements in the ground by repeating the procedure of penetrating the steel shell elements with square hollow cross sections sequentially while connecting the steel shell elements that have already been penetrated and the joint parts. , a method for constructing the steel shell element when constructing the outer shell precedent tunnel by removing the internal earth and sand of the outer shell structure,
A temporary steel pipe that expands the cross section to the adjacent steel shell element side is attached to the steel shell element that is penetrated first,
In a state in which the temporary steel pipe is attached to the steel shell element that has already been penetrated, the steel shell element is penetrated in the next order, and after the construction of this steel shell element is completed, the temporary steel pipe is pulled out. construction method. 2. The steel shell according to claim 1, wherein each of said steel shell elements has a basic cross-sectional dimension defined by a maximum width dimension and a maximum height dimension of a shape obtained by combining a square hollow cross section and said temporary steel pipe, which is constant in the tunnel direction. How the element is constructed. Construction of a steel shell element according to any one of claims 1 and 2, wherein the temporary steel pipe is arranged so that the cross section expands to a range that substantially coincides with the tip end portion of the joint portion projecting to the side of the adjacent steel shell element. Method. The steel shell element construction method according to any one of claims 1 to 3, wherein the temporary steel pipe is fixed to the steel shell element with a bolt, and can be pulled out by removing the bolt. The method for constructing a steel shell element according to any one of claims 1 to 4, wherein the step of inserting the steel shell element while connecting the convex joint of the next steel shell element to the concave joint of the steel shell element that has already been penetrated. The excavator used for penetrating the steel shell element has a shape of the front excavation part that matches the shape of the square hollow cross section of the steel shell element and the temporary steel pipe, and the joint part is attached to the body part. The steel shell element construction method according to any one of claims 1 to 5, wherein an auxiliary cutter is provided for excavating the earth and sand portion corresponding to the above, or the excavator performs over excavation in a range including the joint portion.

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