JP3882882B2 - Steel element and on-site reinforced concrete connection structure, steel element and on-site reinforced concrete connection method, and underground structure construction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure and a method for joining a steel element and an in-situ reinforced concrete used for constructing an underground structure by a non-opening method, and a method for constructing an underground structure by using the steel element and the in-situ reinforced concrete. It is about.
[0002]
[Prior art]
Conventionally, as a method of constructing an underground structure by a non-opening method under a railroad track or road, steel elements are sequentially inserted and combined into the ground by propulsion or towing, and the earth and sand surrounded by the elements are combined. A method of excavating and using a structure made of steel elements (hereinafter referred to as “element structure”) as a main body of an underground structure is used.
[0003]
In such a construction method, when the lower floor slab is made of cast-in-place reinforced concrete, the element at the lower end of the side wall and the lower floor slab need to have a rigid connection structure. In addition, when the cross-sectional shape of the element structure is a shape with the “Sun” sideways or a shape with the “eyes” sideways, the upper-end plate of the middle wall portion arranged in the middle and the corresponding part of the upper floor slab The element may have a rigid coupling structure. Alternatively, for example, when the cross-sectional shape of the element structure is “B” -shaped, these elements may have a rigid coupling structure in a closing portion where the elements are finally joined.
[0004]
In such a case, for example, in the rigid connection structure between the element at the lower end of the side wall part and the reinforced concrete lower floor slab, the reinforcing bar is arranged in the element at the lower end of the side wall part, and these reinforcing bars are connected to the reinforcing bar of the lower floor slab. The cast-in-place concrete is placed to integrate the lower end of the side wall and the lower floor slab.
[0005]
[Problems to be solved by the invention]
However, in the above-described method for constructing an underground structure using elements, a large number of reinforcing bars must be fixed or connected in a limited and narrow space called an element, which is difficult to work, has poor workability, and lowers construction accuracy. There was a problem of doing.
[0006]
The present invention has been made in order to solve the above problems, and the problem to be solved by the present invention is a coupling structure capable of coupling a steel element and a cast-in-place reinforced concrete with good workability and high construction accuracy, And providing such a method.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a steel element and in-situ reinforced concrete connection structure according to the present invention is a steel member that has a rectangular tubular or substantially “U” -shaped cross section and extends in the element axial direction. An element joint portion having a substantially “C” -shaped cross section is provided at the corner portion along the element axial direction, and the elements are joined together by fitting of adjacent element joint portions, and the direction is perpendicular to the element axial direction. A structure in which a steel element capable of transmitting a force in a direction perpendicular to the element axis and a cast-in-place reinforced concrete are coupled, and the “−”-shaped cross section of the steel flat plate portion extending in the element axial direction has a “−”-shaped cross section. The joint joint part of the connection joint member in which the joint joint part having a substantially “C” -shaped cross section is provided along the element axial direction at one end of the “-shaped cross section” and the element of the steel element The connecting joint member is fixed by a hand being fitted, and a grout material is injected and cured in a fitting space formed inside each of the fitted joint parts, and the joint joint of the connection joint member is fixed. A plurality of coupled rebars provided in the vicinity of the other end opposite to the one end provided with the portion and arranged in parallel so as to extend in the direction perpendicular to the element axis are superposed and placed on the cast-in-place reinforced concrete. The steel element and the cast-in-place reinforced concrete are combined by forming a reinforced joint and placing and hardening the cast-in-place concrete.
[0008]
In the combined structure of the steel element and the in-situ reinforced concrete, preferably, the connection joint member has a “−”-shaped cross section of a steel flat plate portion having a “−”-shaped cross section and extending in a longitudinal direction. It is formed by cutting the steel flat plate portion of the straight steel sheet pile provided with a joint joint portion having a substantially “C” -shaped cross section along the longitudinal direction at both ends.
[0009]
Further, in the above-described structure of joining the steel element and the in-situ reinforced concrete, preferably, the joining reinforcing bar is joined to the steel flat plate portion by welding or mechanical joining.
[0010]
Further, in the above-described structure of joining steel elements and cast-in-place reinforced concrete, preferably, the connecting reinforcing bars are surrounded and reinforced by belt reinforcing bars.
[0011]
The first joining method of the steel element and the in-situ reinforced concrete according to the present invention is a corner of a steel member having a rectangular tubular shape or a substantially “U” shaped cross section and extending in the element axial direction. Are provided with element joint portions having a substantially “C” -shaped cross section along the element axial direction, and are joined together by fitting of adjacent element joint portions, and an element shaft that is perpendicular to the element axial direction. A method of joining a steel element capable of transmitting a force in a perpendicular direction and a cast-in-place reinforced concrete, wherein the “−” character of the steel plate portion having a “−”-shaped cross section and extending in the element axial direction is provided. The other end opposite to the one end provided with the joint joint portion of the connection joint member provided with the joint joint portion having a substantially “C” -shaped cross section along the element axial direction at one end portion in the cross section Near the club The coupling joint portion of the coupling member arranged in parallel so that a plurality of coupling rebars extend in a direction perpendicular to the element axis is fitted to the element coupling of the steel element, and then formed in the fitted joint. The joint member is fixed by injecting and hardening a grout material in the fitting space, and then forming a lap joint by superposing and arranging the joint reinforcing bar and the reinforcing steel for the in-situ reinforced concrete. It is characterized by being cast and cured.
[0012]
Further, the second joining method of the steel element and the in-situ reinforced concrete according to the present invention is a corner portion of a steel member having a rectangular tubular shape or a substantially “U” -shaped cross section and extending in the element axial direction. Are provided with element joint portions having a substantially “C” -shaped cross section along the element axial direction, and are joined together by fitting of adjacent element joint portions, and an element shaft that is perpendicular to the element axial direction. A method of joining a steel element capable of transmitting a force in a perpendicular direction and a cast-in-place reinforced concrete, wherein the “−” character of the steel plate portion having a “−”-shaped cross section and extending in the element axial direction is provided. The joint joint portion of the connection joint member, in which the joint joint portion having a substantially “C” -shaped cross section is provided along the element axial direction at one end of the cross section, and the element joint of the steel element are fitted. Then, the connecting joint member is fixed by injecting and hardening a grout material in a fitting space formed in the fitting joint, and then a joint joint portion of the connecting joint member is provided. A plurality of connecting reinforcing bars are juxtaposed in the vicinity of the other end opposite to the one end so as to extend in a direction perpendicular to the element axis, and then the connecting reinforcing bars and the reinforcing bars for in-situ reinforced concrete are overlapped and stacked. It is characterized by forming reinforced joints and casting and hardening in-situ concrete.
[0013]
Further, the underground structure construction method according to the present invention has a rectangular tubular shape or a substantially “U” -shaped cross section and extends in the element axial direction along the element axial direction at the corner of the steel member. A steel element provided with an element joint portion having a substantially “C” -shaped cross section and capable of transmitting a force in a direction perpendicular to the element axis direction, which is perpendicular to the element axis direction, Then, another steel element is inserted into the ground while the element joint portions are fitted to each other, and a grout material is injected into the fitted element joint portion to be hardened. By repeatedly fixing the elements to connect the plurality of steel elements in the ground, and then before the plurality of steel elements are closed, excavate the ground at the closing point to form a closed space, A substantially “C” -shaped cross-section along the element axial direction at one end of the “−”-shaped cross section of a steel flat plate portion having a “−”-shaped cross section and extending in the element axial direction. A plurality of connecting reinforcing bars are juxtaposed so as to extend in the direction perpendicular to the element axis in the vicinity of the other end portion of the connecting joint member provided with the joint portion on the side opposite to the one end portion provided with the joint joint portion. The coupling joint of the cage-shaped member constructed by using two coupling members so that the coupling reinforcing bars are opposed to each other and arranged in parallel in two upper and lower stages and surrounding the coupling reinforcing bars with band reinforcing bars. The cage member is inserted into the excavated closed space while the element joint in the closed space is fitted to each other, and then the cast-in-place concrete is inserted into the closed space in which the cage member is inserted. Cast and harden, then Excavating the ground inside the element structure using an element structure composed of steel elements connected in the ground and a cast-in-place reinforced concrete formed in the enclosed space, and then the element structure It is characterized by constructing an underground structure using as a main body.
[0014]
In the above-described underground structure construction method, preferably, a protective member having a function of a formwork when placing the earth retaining when excavating the closed space and the cast-in-place concrete is disposed at the closed location. The
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0016]
(1) First embodiment
First, a first embodiment of the present invention will be described.
[0017]
FIG. 1 is a cross-sectional view showing the overall configuration of an underground structure according to the first embodiment of the present invention.
[0018]
As shown in FIG. 1, the underground structure 101 is a box-shaped structure having a “B” -shaped cross-sectional shape. The underground structure 101 is composed of a lower floor slab 40 made of in-situ reinforced concrete and an element structure E1 having a cross-section with a shape of “ko”. The lower floor slab 40 and the element structure E1 are rigidly coupled by coupling structure portions 41 and 42.
[0019]
The element structure E1 includes a reference pipe steel element 10 installed at the center position of the upper floor slab, a general steel element 20 installed so as to be adjacent to the reference pipe steel element 10, and an element structure. The corner portion steel elements 30 installed at the four corner positions of the body are combined.
[0020]
FIG. 2 shows the configuration of the reference tube steel element 10 and the general steel element 20 and the joined state. FIG. 2A shows a cross-sectional view of the reference pipe steel element 10 and the general steel element 20. FIG. 2B is an enlarged cross-sectional view showing a joined state of the element joint portions 13 and 23. 2 (A) and 2 (B) are both made of reference tube steel when cut in a plane perpendicular to the direction of the longitudinal axis of the steel element (hereinafter referred to as “element axial direction”). Sectional drawing of the element 10 and the general steel element 20 is shown.
[0021]
As shown in FIG. 2A, the reference pipe steel element 10 has two steel plate members 11, two steel plate members 12, and four element joint portions 13. The steel plate-like member 11 and the other steel plate-like members 11 are arranged so as to face each other and extend in the element axial direction. The steel plate-like member 12 and the other steel plate-like member 12 are arranged so as to face each other and are arranged so as to be perpendicular to the steel plate-like member 11 and extend in the element axial direction. The Thereby, the two steel plate-like members 11 and the two steel plate-like members 12 form a steel member having a rectangular tubular (“B” -shaped) cross section as a whole.
[0022]
Further, steel element joint portions 13 extending along the element axial direction are disposed at each of the four corners of the rectangular tubular cross section formed by the steel plate-like members 11, 12, 11, 12. ing.
[0023]
As shown in FIG. 2 (B), the cross section of the element joint portion 13 is configured to have a substantially “C” -shaped fitting portion 13a and a base portion 13b connected to the back of the fitting portion 13a. . Moreover, the fitting part 13a has the two protrusion parts 13c and 13d. The tip of the protrusion 13c has a bulbous cross section. Further, the middle of the protruding portion 13c and the protruding portion 13d is a recess having an approximately elliptical cross section, and this portion is a groove 13e extending in the element axial direction with an approximately elliptical cross section.
[0024]
2B shows a cross section of the element joint portion 13 at the upper center position in FIG. 2A, but the lower center position, the upper right position, and the lower right position corners in FIG. 2A. The element joint portion 13 having exactly the same shape is also used for the element joint portion 13, and the configuration thereof is exactly the same as that illustrated in FIG.
[0025]
Moreover, each joining location of each steel plate-shaped member 11 and 12 and each element joint part 13 is joined by welding part W1, W2, W3, and W4. The steel plate-like members 11 and 12 and the element joint portions 13 may be joined by mechanical joining such as bolts.
[0026]
When a force in a direction perpendicular to the element axis direction (hereinafter referred to as “element axis perpendicular direction”) is applied to the vicinity of the tip of the protruding portion 13c of the element joint portion 13 by the above-described configuration, for example, FIG. When pulled in the left direction in (B), this tensile force (hereinafter referred to as “first tensile force”) is transmitted from the projecting portion 13c to the base portion 13b, transmitted from the base portion 13b to the steel plate member 11, A tensile force in the left direction in FIG. 2 (B) is applied to the left end of the steel plate-like member 11 in FIG. 2 (B).
[0027]
On the other hand, when a force in the direction perpendicular to the element axis is applied to the vicinity of the tip of the projecting portion 13d of the element joint portion 13, for example, when pulling in the left direction in FIG. 2 (B), this tensile force (hereinafter referred to as “second tension”). 2) is transmitted to the steel plate member 11 from the protruding portion 13d through the base portion 13b, to the left end in FIG. 2 (B) of the steel plate member 11 in the left direction in FIG. 2 (B). That is, the tensile force is applied.
[0028]
From the above, the projecting portions 13c and 13d of the element joint portion 13 and the base portion 13b can resist the force (for example, the first tensile force and the second tensile force) applied from the outside in the direction perpendicular to the element axis. It has a predetermined strength and a predetermined cross section. Further, in consideration of the combined force of the part of the first tensile force and the part of the second tensile force acting on the protruding part 13d of the element joint part 13, a predetermined resistance that can resist the force is given. It has strength and a predetermined cross section. For example, the protrusion 13d has a sufficient thickness.
[0029]
Further, considering that the combined force of the first tensile force and a part of the second tensile force acts on the base portion 13b of the element joint portion 13, a predetermined strength and a predetermined strength that can resist the force are applied. It has a cross section (for example, sufficient thickness). The steel plate-like member 11 has a predetermined strength and a predetermined cross section capable of resisting the force in the direction perpendicular to the element axis transmitted from the element joint portion 13.
[0030]
As shown in FIG. 2A, the general steel element 20 includes two steel plate-like members 21, one steel plate-like member 22, two element joint portions 13, and two steel plate-like members 22. An element joint portion 23 is provided. The steel plate member 21 and the other steel plate members 21 are arranged so as to face each other and extend in the element axial direction. The steel plate-like member 22 is disposed so as to be perpendicular to the steel plate-like members 21 and 21 and extends in the element axial direction. As a result, the two steel plate-like members 21 and the one steel plate-like member 22 form a steel member having a “U” -shaped cross section as a whole.
[0031]
Of the four corners of the “U” -shaped cross section formed by the steel plate-like members 21, 22, 21, the corner opened to the outside, that is, the upper right corner in FIG. A steel element joint portion 23 is disposed along the element axial direction at each of the upper and lower right corners.
[0032]
Of the four corners of the “U” -shaped cross section formed by the steel plate-like members 21, 22, 21, the corner closed to the outside, that is, the upper left corner in FIG. The element joint portion 13 described above is disposed along the element axial direction at each of the portion and the lower left corner.
[0033]
The cross section of the element joint portion 23 is configured to include a substantially “C” -shaped fitting portion 23a and a base portion 23b connected to the back of the fitting portion 23a. Moreover, the fitting part 23a has the two protrusion parts 23c and 23d. The tip of the protrusion 23c has a bulbous cross section. Further, the middle of the projecting portion 23c and the projecting portion 23d is a recess having an approximately elliptical cross section, and this portion is a groove 23e extending in the element axis direction with an approximately elliptical cross section.
[0034]
2B shows a cross section of the element joint portion 23 at the upper center position in FIG. 2A, but the element joint portion 23 at the corner portion at the lower center position in FIG. An element joint portion 23 having exactly the same shape is used, and its configuration is exactly the same as that illustrated in FIG. In addition, the configuration of the element joint portion 13 and the vicinity thereof in the general steel element 20 is exactly the same as the configuration of the element joint portion 13 and the vicinity thereof in the reference pipe steel element 10 described above.
[0035]
Moreover, each joining location of each steel plate-shaped member 21 and 22 and each element joint part 13 and 23 is joined by welding part W5, W6, etc. FIG. The joining of the steel plate-like members 21 and 22 and the element joint portions 13 and 23 may be mechanical joining such as bolts.
[0036]
When a force in the direction perpendicular to the element axis is applied to the vicinity of the tip of the projecting portion 23c of the element joint portion 23 by the above-described configuration, for example, when the force is pulled in the right direction in FIG. , "Third tensile force") is transmitted from the projecting portion 23c to the base portion 23b, from the base portion 23b to the steel plate member 21, and at the right end of the steel plate member 21 in FIG. A tensile force in the right direction in FIG. 2B is applied.
[0037]
On the other hand, when a force in the direction perpendicular to the element axis is applied to the vicinity of the tip of the projecting portion 23d of the element joint portion 23, for example, when pulling in the right direction in FIG. Force ") is transmitted from the projecting portion 23d to the base portion 23b, from the base portion 23b to the steel plate-like member 21, and at the right end of the steel plate-like member 21 in FIG. ) In the right direction.
[0038]
From the above, the projecting portions 23c and 23d of the element joint portion 23 have a predetermined strength capable of resisting the force in the direction perpendicular to the element axis (for example, the third tensile force and the fourth tensile force) applied from the outside. It has a predetermined cross section. Further, in consideration of the fact that the combined force of the fourth tensile force and the bending moment resulting from the fourth tensile force acts on the protruding portion 23d of the element joint portion 23, a predetermined resistance that can resist the force is applied. And has a predetermined cross section. For example, the protrusion 23d has a sufficient thickness.
[0039]
Further, in consideration of the combined force of the third tensile force and the fourth tensile force acting on the base portion 23b of the element joint portion 23, a predetermined strength and a predetermined cross section (for example, resistance to the force) Sufficient thickness). The steel plate-like members 21 and 22 have a predetermined strength and a predetermined cross section that can resist the force in the direction perpendicular to the element axis transmitted from the element joint portions 13 and 23.
[0040]
Next, the construction method of the element structure by the reference pipe steel element 10 and the general part steel element 20 will be described.
[0041]
First, the reference pipe steel element 10 is inserted into the ground in the element axial direction. In this case, an auger drill or the like is provided inside the reference pipe steel element 10, and the element is inserted into the ground while excavating and removing the soil and the like inside the element. Then, each of the element joint parts 23 and 23 provided at the open side corner of the general steel element 20 is replaced with two of the element joint parts 13 of the reference pipe steel element 10 (for example, FIG. The upper left corner joint and the lower left corner joint) in FIG.
[0042]
Thereafter, in a state where these element joint portions 13 and 23 are fitted, the general steel element 20 is made to follow the reference pipe steel element 10 in the same manner as in the case of the reference pipe steel element 10. Insert it into the ground in the direction of the element axis. As a result, the state shown in FIG.
[0043]
In this case, as shown in FIG. 2 (B), the element joint portion 13 of the element joint portion 13 of the reference pipe steel element 10 and the element joint portion 23 of the general steel element 20 which are in a joined state are used. The enlarged tip of the projecting portion 23c of the element joint portion 23 enters and fits into the groove 13e, and the enlarged tip of the projecting portion 13c of the element joint portion 13 enters the groove 23e of the element joint portion 23. It fits in. In this way, the element joint portion 13 of the reference pipe steel element 10 and the element joint portion 23 of the general steel element 20 are fitted to each other, so that the reference pipe steel element 10 and the general steel element 20 are mutually connected. The force in the direction perpendicular to the element axis can be transmitted between them.
[0044]
In the groove 13e, 23e inside the element joint part 13 of the reference pipe steel element 10 and the element joint part 23 of the general steel element 20 fitted as described above, an appropriate one can be provided. At one time, grout materials (not shown) such as non-shrink mortar, non-shrink concrete, resin material, etc. are injected from one end in the axial direction of the element (hereinafter referred to as “injection end”), cured and jointed. May be reinforced. When this grout injection is performed, the joint is fixed, so that it is possible to prevent the plurality of steel elements after being joined from being deformed by bending due to an overload or the like. This reinforcement also improves the force transmission performance in the direction perpendicular to the element axis.
[0045]
Next, in the same manner as described above, each of the element joint portions 23 and 23 provided at the open side corners of other new general steel elements 20 is already inserted into the ground. The element joint portions 13 and 13 provided at the corners on the closing side of 20 are fitted and joined. And in the state which fitted both joints, the new general part steel element 20 is inserted in the underground toward the element axial direction, along with the already inserted general part steel element 20.
[0046]
Hereinafter, by repeating the general element insertion process sequentially as described above, an element structure can be configured by the steel elements 10 and 20 inserted into the ground and joined to each other. For example, a flat structure or an element structure having a shape surrounded by a semicircle, a circle, an ellipse, or the like.
[0047]
Next, concrete or the like is filled in each element as necessary. Next, the element structure formed in the ground is used as a protective work to excavate the soil and the like inside the element structure. Next, an underground structure can be constructed by performing construction such as covering the inner surface of the element with concrete.
[0048]
When the element structure has a “B” -shaped cross section or the like, a corner where the element bends at a right angle is required. In this corner portion, a corner portion constituting element 30 having a different configuration from the reference pipe steel element 10 and the general portion steel element 20 is used.
[0049]
Next, the configuration of the corner steel element 30 will be described with reference to FIG. FIG. 3 shows a cross-sectional view of a connecting structure 41 between the corner steel element 30 that is the lower end position of the left side wall of the element structure E1 shown in FIG. 1 and the left end of the lower floor slab 40. FIG. 3 shows a cross-sectional view of the corner steel element 30 and the coupling structure 41 when cut along a plane perpendicular to the element axial direction.
[0050]
As shown in FIG. 3, the corner steel element 30 has five steel plate members 31, 31, 32, 34, 34, two element joint parts 13, and two element joint parts 23. is doing. The steel plate-like member 31 and the other steel plate-like member 31 are arranged so as to face each other and extend in the element axial direction. The steel plate-like member 34 and the other steel plate-like member 34 are arranged so as to face each other and are arranged so as to be perpendicular to the steel plate-like member 31 and extend in the element axial direction. The The steel plate-like member 32 is arranged so as to be perpendicular to the steel plate-like member 31 and parallel to the steel plate-like member 34, and extends in the element axial direction. Thereby, the five steel plate-shaped members 31, 31, 32, 34, and 34 form a steel member having a rectangular tubular cross section as a whole.
[0051]
Further, of the four corners of the rectangular tubular cross section formed by the steel plate-like members 31, 31, 32, 34, 34, one direction in the direction perpendicular to the element axis, for example, in the vertical direction in FIG. Element joint portions 23, 23 are provided along the element axial direction at two corners adjacent to each other, that is, at the upper left corner and the upper right corner in FIG.
[0052]
Also, the elements along the element axial direction are arranged at two corners adjacent to each other in the other direction perpendicular to the above-described vertical direction, for example, the left-right direction in FIG. 3, that is, the upper right corner and the lower right corner in FIG. Joint portions 13 and 13 are provided.
[0053]
The structure of each element joint part 13 and 23 is completely the same as the above. The steel plate-like members 31, 32, and 34 have a predetermined strength and a predetermined cross section that can resist the force in the direction perpendicular to the element axis transmitted from the element joint portions 13 and 23. Moreover, each joining location of each steel plate-shaped member 31, 32, 31, 34 and each element joint part 13 and 23 is joined by the welding part. This joining may be a mechanical joining such as a bolt.
[0054]
The corner steel elements 30 are also provided at the upper right, lower right, and upper left corners of the element structure E1. With the above-described configuration, the corner steel element 30 has a component in each direction of the “L” -shaped corner portion of the force in the direction perpendicular to the element axis, for example, the horizontal direction (horizontal direction) in FIG. The component can be transmitted by the horizontal element joint portion 13 provided on the corner steel element 30 side and the joint portion (for example, the element joint portion 23) provided on the counterpart side. Of the force perpendicular to the element axis, the component in the vertical direction (vertical direction) includes the vertical element joint 13 provided on the corner steel element 30 side and the joint provided on the mating side. It can be transmitted by a part (for example, element joint part 23).
[0055]
The insertion of the corner portion steel element 30 into the ground is exactly the same as the case of the reference portion steel element 10 and the general portion steel element 20 described above, and is adjacent to the ground portion already inserted into the ground. Insert it along the element. The same applies to the general steel element 20 adjacent to the lower corner steel element 30.
[0056]
For the corner steel element 30 described above, a large tensile force may be generated inside the corner of the element structure, for example, the upper right corner in FIG. The steel plate-like member 34 can be made to bear and the strength of the element structure can be increased.
[0057]
Further, when the tensile force inside the corner portion (upper right corner portion in FIG. 3) of the element structure is small, the upper steel plate member 34 may be omitted. Alternatively, when construction is performed (when the corner steel element 30 is inserted), the steel plate-like member 34 is omitted, and a “U” -shaped cross section is provided. The steel plate-like member 34 may be attached by, for example, mechanical joining. The lower steel plate-like member 34 can be added or omitted as appropriate.
[0058]
In the underground structure 101 of the first embodiment, the lower floor slab 40 is made of cast-in-place reinforced concrete, and the lower end of the side wall of the element structure E1 and the lower floor slab 40 are rigidly connected by connecting structures 41 and 42. The coupling structure 41 at the lower left corner of the underground structure 101 and the coupling structure 42 at the lower right corner have exactly the same configuration. Next, the structure of the joint structure 41 at the lower left corner of the underground structure 101 will be described.
[0059]
As shown in FIG. 3, the coupling structure portion 41 includes a connection joint member 43, a coupling reinforcing bar 44, and a cast-in-place concrete 45.
[0060]
FIG. 4 is a diagram illustrating the configuration of the connection joint member 43 in the coupling structure portion 41 illustrated in FIG. 3. As shown in the cross-sectional view of FIG. 4A (cross-sectional view when cut along a plane perpendicular to the element axial direction), the connection joint member 43 has a so-called straight steel sheet pile 46 along the center line in the longitudinal direction of the sheet pile. And cut into two equal parts.
[0061]
The connection joint member 43 has a steel flat plate portion 43a and a joint joint portion 43b. The steel flat plate portion 43a is a flat plate portion made of steel having a “−”-shaped cross section and extending in the element axial direction. The joint joint 43b is made of steel, and is a portion of a substantially “C” -shaped cross section formed along the element axial direction at one end of the “−”-shaped cross section of the steel flat plate portion 43a. It has the same configuration as the element joint portion 13 described above.
[0062]
FIG. 4B is a perspective view showing the arrangement relationship between the connecting joint member 43 and the coupling reinforcing bar 44 and the configuration of both. As shown in FIG. 4B, among the steel flat plate portion 43a of the connection joint member 43, a plurality of coupling rebars 44 are provided in the vicinity of the other end portion on the side opposite to the one end portion where the coupling joint portion 43b is provided. Provided and arranged side by side so as to extend along a direction perpendicular to the element axial direction. These connecting reinforcing bars 44 are joined to the steel flat plate portion 43 a by a welded portion 47. The joining of the steel flat plate portion 43a and the connecting reinforcing bar 44 may be a mechanical joining such as a bolt.
[0063]
With the above structure, as shown in FIG. 3, the joint joint portion of the element joint portion 13 at the upper right corner of the steel element 30 at the lower corner of the left side wall of the element structure E1 and the joint joint member 43 at the upper stage is provided. 43b are fitted to each other, and the element joint 13 at the lower right corner of the corner steel element 30 and the joint joint 43b of the lower connection joint member 43 are fitted to each other, thereby making the corner steel. A force in a direction perpendicular to the element axis can be transmitted between the element 30 and the coupling structure portion 41.
[0064]
Further, as shown in FIG. 3, the jointed reinforcing bar 44 joined to the connection joint member 43 is provided with a reinforced concrete joint 49 in place of the in-situ reinforced concrete of the lower floor slab 40. Accordingly, the force transmitted from the element joint 13 of the corner steel element 30 at the lower end of the left side wall of the element structure E1 to the connection joint member 43 by the joint joint 43b from the joint rebar 44 to the on-site reinforced concrete rebar. 49 is transmitted to the lower floor slab 40.
[0065]
Further, as shown in FIG. 3, a band reinforcing bar 48 that surrounds the band may be arranged in the connecting reinforcing bar 44 to further reinforce it.
[0066]
Next, the 1st method for constructing the connection structure part 41 is demonstrated.
[0067]
First, two members (hereinafter referred to as “joining members”) formed in a state shown in FIG. 4B by welding a plurality of joint reinforcing bars 44 to the connection joint member 43 are prepared in advance.
[0068]
Next, the earth and sand in the element structure E1 is excavated to the bottom position of the corner steel element 30 (the position of the steel plate member 32 in FIG. 3).
[0069]
Next, the coupling joint portion 43b of one coupling member is fitted into the element coupling portion 13 at the upper right corner of the corner steel element 30, and inserted so as to slide in the element axial direction. Thereafter, the grout material is injected into the inside of the fitting space (the portion corresponding to 13e or 23e in FIG. 2A) formed inside the joint joint portion 43b and the element joint portion 13 that are fitted to each other, and is cured. . Thereby, one coupling member can be fixed to the corner steel element 30.
[0070]
Similarly, the coupling joint portion 43b of the other coupling member is fitted into the element coupling portion 13 at the lower right corner of the corner steel element 30, and is inserted so as to slide in the element axial direction, and fitted together. A grout material is injected into a fitting space formed inside the joint joint portion 43 b and the element joint portion 13 and hardened, and the other joint member is fixed to the corner steel element 30.
[0071]
Next, the connecting reinforcing bar 44 of the connecting member and the in-situ reinforced concrete reinforcing bar 49 of the lower floor slab 40 are overlapped to form a lap joint. Further, if necessary, the periphery of the joint reinforcing bar 44 is surrounded by the band reinforcing bar 48 to reinforce. Thereafter, the cast-in-place concrete 45 is placed and cured. Thereby, the lower floor 40 of the underground structure 101 and the corner steel element 30 can be rigidly coupled.
[0072]
Next, the 2nd method for constructing the connection structure part 41 is demonstrated.
[0073]
First, the earth and sand in the element structure E1 is excavated to the bottom position of the corner steel element 30 (the position of the steel plate member 32 in FIG. 3).
[0074]
Next, the joint joint portion 43b of one connection joint member 43 is fitted into the element joint portion 13 at the upper right corner of the corner steel element 30, and is inserted so as to slide in the element axial direction. Thereafter, the grout material is injected into the inside of the fitting space (the portion corresponding to 13e or 23e in FIG. 2A) formed inside the joint joint portion 43b and the element joint portion 13 that are fitted to each other, and is cured. . Thereby, one connection joint member 43 can be fixed to the corner steel element 30.
[0075]
Next, among the connecting joint members 43, a plurality of connecting reinforcing bars 44 are arranged by welding or the like so as to extend in the direction perpendicular to the element axis in the vicinity of the other end opposite to the one end provided with the connecting joint 43b. Bonded to the state shown in FIG.
[0076]
Next, in the same manner as described above, the joint joint portion 43b of the other connection joint member 43 is fitted to the element joint portion 13 at the lower right corner of the corner steel element 30, and is slid in the element axial direction. The grout material is injected into the fitting space formed inside the joint joint portion 43b and the element joint portion 13 which are inserted and fitted to each other and hardened, and the other joint joint member 43 is made of a corner steel element. Fix to 30.
[0077]
Thereafter, in the same manner as described above, among the other connecting joint members 43, a plurality of connecting reinforcing bars 44 extend in the direction perpendicular to the element axis in the vicinity of the other end opposite to the one end provided with the connecting joint 43b. In this way, they are aligned and joined by welding or the like to obtain a state as shown in FIG.
[0078]
Next, the joint reinforcing bar 44 and the in-situ reinforced concrete reinforcing bar 49 of the lower floor slab 40 are overlapped to form a lap joint. Further, if necessary, the periphery of the joint reinforcing bar 44 is surrounded by the band reinforcing bar 48 to reinforce. Thereafter, the cast-in-place concrete 45 is placed and cured. Thereby, the lower floor 40 of the underground structure 101 and the corner steel element 30 can be rigidly coupled.
[0079]
As shown in FIG. 5, the band reinforcing bars may be arranged like 48a, 48b, and 48c by sequentially shifting the surrounding connecting reinforcing bars 44 so as to form a so-called “staggered arrangement”. By comprising in this way, it can be set as a firmer structure so that the rising part of a band reinforcement may not concentrate.
[0080]
(2) Second embodiment
Next, a second embodiment of the present invention will be described.
[0081]
FIG. 6 is a cross-sectional view showing the overall configuration of an underground structure that is the second embodiment of the present invention.
[0082]
As shown in FIG. 6, the underground structure 102 is a box-shaped structure having a “B” -shaped cross-sectional shape. The underground structure 102 includes an element structure E2 having a cross-sectional shape in which only a part near the center of the lower part of the “R” shape is cut off, and a closed structure portion 51.
[0083]
The element structure E2 includes a reference pipe steel element 10 installed at the center position of the upper floor slab, a general steel element 20 installed so as to be adjacent to the reference pipe steel element 10, and an element structure. Since the corner steel elements 30 installed at the four corner positions are combined, the structure of each steel element 10, 20, 30 is exactly the same as in the first embodiment. The description is omitted.
[0084]
The difference between the underground structure 102 of the second embodiment and the underground structure 101 of the first embodiment is that it includes a closed structure portion 51 that is provided between the general steel elements 20 and is rigidly coupled. .
[0085]
FIG. 7 shows a configuration of the closing structure portion 51. FIG. 7 shows a cross-sectional view of the steel element cut along a plane perpendicular to the element axial direction.
[0086]
As shown in FIG. 7, the closing structure 51 includes a cage member 59, protective members 52 a and 52 b, and a cast-in-place concrete 55.
[0087]
In the cage member 59, another connecting joint member 43 is joined by welding or the like to the end of the connecting bar 44 (the end opposite to the connecting joint member 43) of the connecting member as shown in FIG. 4B. Two members (hereinafter referred to as “fence-like members”) are used, the two fence-like members 57a and 57b are arranged opposite to each other so that the connecting reinforcing bars 44 are parallel to each other, and each of the fence-like members 57a and 57b. The rebars 44 are surrounded by the rebars 58, and the rebars 58 are appropriately joined to the rebars 44. The steel flat plate portion 43a and the connecting rebar 44 in the fence-like member may be joined by mechanical joining such as bolts.
[0088]
With the structure as described above, as shown in FIG. 7, the element joint portion 23 at the upper right corner of the general steel element 20L on the left side in the vicinity of the lower center of the element structure E2 (see FIG. 6), and the cage member The joint joint 43b at the left end of the upper fence-like member 57a of the upper 59 is fitted to each other, the element joint 23 at the lower right corner of the left general steel element 20L, and the lower fence-like form of the cage-like member 59 The coupling joint portion 43b at the left end of the member 57b is fitted to each other.
[0089]
Further, the element joint 23 at the upper left corner of the right general steel element 20R near the lower center of the element structure E2 (see FIG. 6) and the right end of the upper fence-like member 57a of the cage member 59 are connected. The joint 43b fits together, and the element joint 23 at the lower left corner of the right general steel element 20R and the joint joint 43b at the right end of the lower fence-like member 57b of the cage member 59 are fitted together. Match.
[0090]
As shown in FIG. 7, in the upper and lower fence members 57a and 57b constituting the cage member 59, the connecting joint members 43 and the connecting reinforcing bars 44 at both ends are joined by welding or the like.
[0091]
With such a configuration, the force in the direction perpendicular to the element axis can be transmitted between the left general-part steel element 20L, the closing structure 51, and the right general-part steel element 20R.
[0092]
Next, the construction method of the closed structure part 51 is demonstrated.
[0093]
First, the cage member 59 is prepared in advance.
[0094]
Next, the above-described reference pipe steel element 10, the general part steel element 20, the element joint parts 13 and 23 of the corner steel element 30, etc. are inserted into the ground and fitted together. The grout material is injected into the element joint and hardened, and the steel elements are repeatedly fixed. The multiple steel elements are connected in the ground, and a portion near the lower center of the “B” character (general part steel) An element structure E2 having a cross section with a shape lacking between the elements 20L and 20R is formed in the ground.
[0095]
Next, the protective member 52a is inserted into the ground above this location (hereinafter referred to as the “close location”) in a state where the general steel elements 20L and 20R are not closed. Similarly, the protective member 52b is inserted into the ground below the closing location. Steel plates or the like are used as the protection members 52a and 52b. In this case, both ends of the protection members 52a and 52b are joined to the general steel elements 20L and 20R by a joining member 53 such as welding. The joining of the joining member 53 to the general steel element 20L or the like may be a mechanical joining such as a bolt.
[0096]
Next, as shown in FIG. 8A, the protective members 52a and 52b are used as earth retaining means, the ground inside the portion surrounded by the protective members 52a and 52b is excavated and removed, and the closed space 54 Form.
[0097]
After that, as shown in FIG. 8 (B), the coupling joint portion 43b of the cage member 59 described above is fitted to the element joint portion 23 such as the general steel element 20L and inserted so as to slide in the element axial direction. Then, the cage member 59 is inserted into the excavated closed space 54.
[0098]
Next, as shown in FIG. 8C, using the protective members 52a and 52b as a concrete formwork, the cast-in-place concrete 55 is placed in the closed space 54 in which the cage member 59 is inserted and cured. . Thereby, the closing structure part 51 is completed, and the element structure E2 is closed with a “B” -shaped cross section.
[0099]
Next, using the “B” -shaped structure closed as described above as a protective work, the ground inside is excavated. Next, an underground structure is constructed using the closed “B” -shaped structure as the main body structure.
[0100]
If constructed in this way, the element structure can be rigidly closed and closed in a short time, and the construction accuracy can be improved.
[0101]
The present invention is not limited to the above embodiments. Each of the embodiments described above is an exemplification, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and has the same operational effects can be used. It is included in the technical scope of the present invention.
[0102]
For example, in the said embodiment, although the example which forms a connection joint member (for example, 43) by cut | disconnecting a linear steel sheet pile was demonstrated, this invention is not limited to this example, The connection joint member of another structure For example, the connection joint member may be formed by joining an element joint portion (for example, 13 or 23) to one side end of a strip-shaped steel plate by welding or mechanical joining.
[0103]
In the above embodiment, the element structure is formed by the reference tube steel element 10 and the corner steel element 30 having a rectangular tubular cross section, and the general steel element 20 having a substantially “U” -shaped cross section. Although the example which comprises is explained, the present invention is not limited to this example, steel elements of other constitutions, for example, a substantially “day” shape, a substantially “eye” shape, a substantially “field” shape, It may be a steel element having a substantially “circle” -shaped cross section.
[0104]
Moreover, in the said embodiment, although the case where the element coupling part (for example, 13 or 23) was provided in the corners, such as the reference | standard pipe steel element 10, etc. was mentioned as an example, this invention is shown in this example. It is not limited, You may comprise so that an element coupling part may be provided in the steel element of another structure, for example, the intermediate part of the edge | side of a steel element.
[0105]
【The invention's effect】
As described above, according to the present invention, a connection joint member having a joint joint portion is used, and the joint joint portion is fitted to an element joint portion of an existing steel element and used as a reinforcement member for in-situ concrete. Therefore, even in a narrow space of the steel element, there is an advantage that the work is easy, the workability is good, and the work accuracy is improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an overall configuration of an underground structure according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a reference pipe steel element and a general part steel element in the underground structure of FIG. 1;
3 is a cross-sectional view showing a configuration of a connecting structure portion of a corner steel element and a lower floor slab in the underground structure of FIG. 1;
4 is a diagram showing a configuration of a connection joint member in the coupling structure portion of FIG. 3;
FIG. 5 is a diagram showing a state of arrangement of band reinforcing bars in the coupling structure portion of FIG. 3;
FIG. 6 is a cross-sectional view showing an overall configuration of an underground structure according to a second embodiment of the present invention.
7 is a diagram showing a configuration of a closed structure portion in the underground structure of FIG. 6;
8 is a diagram illustrating a construction method of a closed structure portion in the underground structure of FIG.
[Explanation of symbols]
10 Reference pipe steel element
11, 12 Steel plate-like member
13 Element joint
13a Fitting part
13b base
13c, 13d Projection
13e groove
20, 20L, 20R General steel element
21, 22 Steel plate-like member
23 Element joint
23a Fitting part
23b base
23c, 23d Projection
23e groove
30 Corner steel element
31, 32, 34 Steel plate-like members
40 Lower floor version
41, 42 Bonding structure
43 Connection joint members
43a Steel plate
43b Joint joint
44 Reinforcing bar
45 Cast-in-place concrete
46 Straight steel sheet pile
47 Welded part
48, 48a-48c Reinforcing bars
49 Reinforcement for on-site reinforced concrete
51 Closure structure
52a, 52b Protective member
53 Joining members
54 closed space
55 On-site concrete
57a, 57b Fence-like member
58 Reinforcing bar
59 Basket-shaped member
101, 102 Underground structure
E1, E2 element structure
L Chuo Line
W1-W6 weld zone

Claims (8)

A steel member extending in the element axial direction is provided with an element joint portion having a substantially “C” -shaped cross section along the element axial direction, and the elements are joined to each other by fitting adjacent element joint portions. It is a structure that joins steel elements and in-situ reinforced concrete that can transmit the force in the direction perpendicular to the element axis that is perpendicular to the element axis direction,
A joint joint portion having a substantially “C” -shaped cross section along the element axial direction at one end of the “−”-shaped cross section of the steel flat plate portion having a “−”-shaped cross section and extending in the element axial direction The joint joint part of the connection joint member provided with the element joint of the steel element is fitted, and a grout material is injected into the fitting space formed inside each of the fitted joint parts and hardened. By doing so, the connecting joint member is fixed, and the connecting joint member is provided in the vicinity of the other end portion of the connecting joint member opposite to the one end portion where the connecting joint portion is provided. The steel elements and the cast-in-place reinforced steel joint are formed by superposing and arranging a plurality of jointed reinforcing bars and the steel-reinforced concrete for the cast-in-place reinforced concrete to form a lap joint. Coupling structure steel elements and cast-in-place reinforced concrete, characterized in that REITs are combined. In the combined structure of the steel element according to claim 1 and on-site reinforced concrete,
The connection joint member has a substantially “C” -shaped cross section along the longitudinal direction at both ends of the “−”-shaped cross section of the steel flat plate portion having a “−”-shaped cross section and extending in the longitudinal direction. A steel element and in-situ reinforced concrete connection structure formed by cutting the steel flat plate portion of a straight steel sheet pile provided with a joint joint portion of the steel plate along the longitudinal direction. In the combined structure of the steel element according to claim 1 and on-site reinforced concrete,
The joint structure of the steel element and the in-situ reinforced concrete, wherein the joint reinforcement is joined to the steel flat plate portion by welding or mechanical joining. In the combined structure of the steel element according to claim 1 and on-site reinforced concrete,
The bonded reinforcing bar is surrounded and reinforced by a band reinforcing bar, and is a bonded structure of a steel element and a cast-in-place reinforced concrete. A steel member extending in the element axial direction is provided with an element joint portion having a substantially “C” -shaped cross section along the element axial direction, and the elements are joined to each other by fitting adjacent element joint portions. A method of joining a steel element capable of transmitting a force perpendicular to the element axis direction, which is a direction perpendicular to the element axis direction, and a cast-in-place reinforced concrete,
A joint joint portion having a substantially “C” -shaped cross section along the element axial direction at one end of the “−”-shaped cross section of the steel flat plate portion having a “−”-shaped cross section and extending in the element axial direction A connecting member in which a plurality of connecting reinforcing bars extend in a direction perpendicular to the element axis in the vicinity of the other end opposite to the one end where the connecting joint is provided. The coupling joint portion of the steel element and the element joint of the steel element are fitted,
Subsequently, the coupling member is fixed by injecting and curing a grout material in a fitting space formed in the fitted joint.
Next, a method of joining a steel element and a cast-in-place reinforced concrete, characterized in that the jointed reinforcing bar and the steel-reinforced concrete for in-situ reinforced concrete are arranged to overlap to form a lap joint, and the cast-in-place concrete is cast and cured. A steel member extending in the element axial direction is provided with an element joint portion having a substantially “C” -shaped cross section along the element axial direction, and the elements are joined to each other by fitting adjacent element joint portions. A method of joining a steel element capable of transmitting a force perpendicular to the element axis direction, which is a direction perpendicular to the element axis direction, and a cast-in-place reinforced concrete,
A joint joint portion having a substantially “C” -shaped cross section along the element axial direction at one end of the “−”-shaped cross section of the steel flat plate portion having a “−”-shaped cross section and extending in the element axial direction And fitting the joint joint portion of the connection joint member provided with the element joint of the steel element,
Subsequently, the connecting joint member is fixed by injecting and curing a grout material in a fitting space formed in the fitted joint,
Next, a plurality of coupling reinforcing bars are arranged in parallel so as to extend in the direction perpendicular to the element axis in the vicinity of the other end portion on the side opposite to the one end portion where the coupling joint portion of the connection joint member is provided,
Next, a method of joining a steel element and a cast-in-place reinforced concrete, characterized in that the jointed reinforcing bar and the steel-reinforced concrete for in-situ reinforced concrete are arranged to overlap to form a lap joint, and the cast-in-place concrete is cast and cured. A steel member extending in the element axial direction is provided with an element joint portion having a substantially “C” -shaped cross section along the element axial direction, and the force in the direction perpendicular to the element axial direction is perpendicular to the element axial direction. Insert the steel element that can be transmitted into the ground with the element axial direction as the insertion direction,
Next, another steel element is inserted into the ground while fitting the element joints to each other, and grout material is injected into the fitted element joints and cured to fix the steel elements. Repeatedly to connect multiple steel elements in the ground,
Next, before the plurality of steel elements are closed, the closed space is excavated to form a closed space,
Next, a substantially “C” -shaped cross-section is bonded to one end of the “−”-shaped cross section of the steel flat plate portion having a “−”-shaped cross section and extending in the element axial direction along the element axial direction. A plurality of connecting reinforcing bars are juxtaposed so as to extend in the direction perpendicular to the element axis in the vicinity of the other end portion of the connecting joint member provided with the joint portion on the side opposite to the one end portion provided with the joint joint portion. The coupling joint of the cage-shaped member constructed by using two coupling members so that the coupling reinforcing bars are opposed to each other and arranged in parallel in two upper and lower stages and surrounding the coupling reinforcing bars with band reinforcing bars. The cage-shaped member is inserted into the excavated closed space while the element joint in the closed space is fitted to each other, and then the cast-in-place concrete is inserted into the closed space in which the cage-shaped member is inserted. Cast and harden,
Then, excavating the ground inside the element structure as a protective work element structure composed of steel elements connected in the ground and on-site reinforced concrete formed in the closed space,
Next, an underground structure construction method comprising constructing an underground structure using the element structure as a main body. In the underground structure construction method according to claim 7,
The underground construction method according to claim 1, wherein a protective member having a function of a formwork for placing the earth retaining when excavating the closed space and the cast-in-place concrete is disposed at the closed location.

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