JP3564675B2 - Reinforcement method of rolled steel plate and existing column - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rolled-up steel plate and a method of reinforcing an existing column, by rolling up a steel plate around an existing column such as a leg or a bridge pier of various viaducts to perform seismic reinforcement.
[0002]
[Prior art]
In view of the damage to existing pillars such as piers caused by the Great East Japan Earthquake, seismic reinforcement of existing pillars is attracting attention. As a seismic retrofitting technique, a technique of surrounding the existing column with a steel plate and then filling the steel plate and the existing column with a solidifying material such as mortar to reinforce the steel is disclosed in Japanese Patent Publication No. 53-43259 and JP It is disclosed in JP-A-61-270464.
When a steel plate is wound around an existing column, a steel pipe cannot be installed from the upper portion of the existing column because a road, a railroad, and the like exist above the existing column.
Therefore, a steel plate in which a plurality of steel pipes are horizontally divided is assembled from the side of the existing column, and the respective steel plates are joined by field welding or bolting.
[0003]
[Problems to be solved by the invention]
However, when welding and joining between steel plates, not only does it take a long time to perform the work, but also there is a large variation in quality, and there remains uneasiness in terms of reliability. In addition, welding on site is susceptible to weather and temperature, and the process is affected by weather. Furthermore, it has been pointed out that vibrations generated by the running of trains and vehicles adversely affect welding. Further, when bolting between steel plates, there is a problem that it takes time and effort to fix a large number of bolts.
[0004]
The present invention has been made in view of the above points, and has as its object to provide a method for reinforcing a wound steel plate and an existing column that can be easily and quickly constructed without any on-site welding or bolt fixing work. Is to do.
Still another object of the present invention is to provide a highly reliable method for reinforcing a wound steel plate and an existing column.
[0005]
[Means for Solving the Problems]
The present invention is a rolled steel plate wound around the outer periphery of an existing column, comprising a plurality of divided steel plates having a length substantially the same as the entire length of the existing column, and on both end portions of each of the divided steel plates, A wrapped steel plate wherein a joint portion that can be fitted to each other by sliding in a longitudinal direction is formed intermittently.
Further, the present invention relates to a rolled steel plate wound around an outer periphery of an existing column having a restriction in the sky, wherein a plurality of divided steel plates exhibiting a length substantially equal to the entire length of the existing column, and a length substantially equal to the entire length of the existing column. A plurality of intermediate plates that seal between the divided steel plates, and joint portions that can be mutually fitted to both end portions of each of the divided steel plates and the intermediate plates by sliding the plate body in the longitudinal direction. Is formed intermittently.
Furthermore, in the present invention, in the rolled steel sheet, a plurality of bolts for finely adjusting the verticality of the plate body are provided on the divided steel sheet while the joint portion is fitted in a tensile state by obtaining a reaction force from the existing column. Characterized by the following:
Further, the present invention provides the wound steel plate, wherein the joint portion is formed by forming a dovetail groove capable of fitting another hook portion between the envelope portion and the hook portion. A rolled steel plate, wherein one of the portions is formed intermittently and the other is formed continuously.
Further, the present invention provides a method of reinforcing an existing column in which a steel plate is wound around an outer periphery of an existing column, and a filler is filled between the steel plate and the existing column to reinforce the existing column, wherein any one of the above-described rolled steel plates is used. A method for reinforcing an existing column, characterized in that each divided steel plate or intermediate plate is abutted from the side of the existing column and slid relatively up and down to connect and join together the joints. is there.
Further, the present invention relates to a method for reinforcing an existing column in which a steel plate is wound around the outer periphery of an existing column, and a filler is filled between the steel plate and the existing column to reinforce the existing column, wherein the above-described wound steel plate is used. Abutting each split steel plate or intermediate plate from the side of the column and sliding it relatively up and down to connect the joints, rotating the bolts and fitting the joints in tension, A method for reinforcing an existing column, characterized by finely adjusting the verticality of the body.
[0006]
Embodiment 1 of the present invention
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0007]
<A> Structure of Rolled Steel Sheet FIG. 1 and FIG. The rolled steel plate 10 is a reinforcing material that is provided from the side of the existing column 20 and is composed of divided steel plates 11 and 12 having a U-shaped cross section.
[0008]
<B> Split Steel Plates The total length of each of the split steel plates 11 and 12 has substantially the same length as the entire length of the existing column 20, and a joint portion 13 and a cutout portion 14 that can be fitted to each other are provided at both ends. Are alternately formed along the longitudinal direction of each of the divided steel plates 11 and 12.
The joint portions 13 and 13 allow the divided steel plates 11 and 12 to slide in the axial direction, but may have a “dovetail structure” that prevents separation of the divided steel plates 11 and 12 in the direction orthogonal to the axial direction. For example, a known steel sheet pile joint structure is suitable. More preferably, it is economical to use a steel sheet pile with a joint intermittently welded at a factory or the like on the side end of a steel sheet bent in a U-shape.
In addition, the pitch and the number of joints 13 to be formed are appropriately selected and determined, and the sectional shape of each of the divided steel plates 11 and 12 is not limited to the U-shape, and may be an arc or another shape. good.
[0009]
<C> Bolts and bolts 15 are provided in each of the divided steel plates 11 and 12 at a plurality of positions for the purpose of eliminating rattling of the joint portions 13 and 13 in the fitted state and maintaining a constant distance from the existing column 20. It is screwed on.
[0010]
[Action]
Next, a method of reinforcing the existing column 20 using the above-described wound steel plate 10 will be described.
[0011]
<A> Excavation (Fig. 3)
The root of the existing column 20 is excavated until the top end of the foundation 21 of the existing column 20 is exposed.
[0012]
<B> Rolling of split steel sheets (Figs. 2 to 5)
As shown in FIG. 3, one of the divided steel plates 11 is provided on one side of the existing column 20. The lower part of the divided steel plate 11 is supported on the top end of the base part 21. Next, the other split steel plate 12 is provided on the other side of the existing column 20.
At this time, as shown in FIG. 2, after the joint portion 13 of the other split steel plate 12 is horizontally inserted into the cutout portion 14 of the one split steel plate 11, the split steel plates 11 and 12 are relatively slid vertically. Then, as shown in FIG. 5, the joint portions 13, 13 of the two split steel plates 11, 12 are fitted and connected. In this way, the winding steel sheet 10 according to the present invention is completed by the operation of abutting the divided steel sheets 11 and 12 and slightly shifting the same in the vertical direction. Also, a slight gap is formed between the upper part of the wound steel plate 10 and the upper structure 22 of the existing column 20.
[0013]
<C> The bolted steel plate 10 is lifted up until the upper end of the bolted steel plate 10 of the bolt comes into contact with the upper structure 22 of the existing column 20, and between the lower end of the steel plate 10 and the foundation 21. Temporary receiving is performed with the temporary receiving material 16 interposed.
It is not possible to secure the verticality of the rolled-up steel plate 10 only by standing the rolled-up steel plate 10 around the existing column 20, and it is necessary to adjust the verticality. In addition, as shown in FIG. 8, if looseness is left between the joint portions 13 to be loosely fitted, the strength is a weak point. Therefore, the bolts 15 are tightened by obtaining the reaction force from the existing column 20, and a tensile force is applied to the joints 13, 13 as shown in FIG. Finely adjust the verticality of 11 and 12.
[0014]
<D> Filling As shown in FIG. 1, a filler 17 such as mortar or epoxy resin is filled between the wound steel plate 10 and the existing column 20, and as shown in FIG. A compacting material 18 such as mortar is poured into a lower portion of the base 20 to fix the root, and then backfilled to complete the construction.
When filling the filler 16, the steel plate 10 is closed with a plate or the like so as not to leak from the defective portion 14 of the wound steel plate 10. Further, the bolt 15 is removed after the filler 17 is hardened.
[0015]
Embodiment 2 of the present invention
FIG. 10 shows another rolled steel plate 10a applied to the existing column 20 having a large cross section. The rolled steel plate 10a is configured by connecting an intermediate plate 23 between a plurality of divided steel plates 19 to 22 having an L-shaped cross section. The bolts 15 are screwed onto each surface of each of the divided steel plates 19 to 22, and the side ends of each of the divided steel plates 19 to 22 and both side ends of the intermediate plate 23 are described above along the longitudinal direction. The joint 13 is formed intermittently. A well-known steel sheet pile may be used for the intermediate plate 23 as it is.
In the present embodiment, the operation and construction method for connecting the divided steel plates 19 to 22 and the intermediate plate 23 via the joint portion 13 are the same as those in Embodiment 1 described above, and thus will be described. Is omitted.
[0016]
Third Embodiment of the Invention
11 and 12 show another joint structure for connecting the divided steel plates 11 and 12 of FIG. 1 described above, the intermediate plate 23 and the divided steel plates 19 to 22 of FIG. In the present embodiment, for convenience of description, the respective connected plate bodies 11, 12, 19 to 23, and 23 are collectively described as two steel plates 24 and 25.
At the side end of each of the steel plates 24 and 25, a dovetail groove 13c having a C-shaped cross section is formed between the wrapping portion 13a and the hooking portion 13b, into which another hooking portion 13b can be fitted. While the wrapping portions 13a of the steel plates 24 and 25 are formed continuously, the hooking portions 13b are formed intermittently along the longitudinal direction, and the hooking portions 13b and the hooking portions 13b are formed intermittently. Between the hooks 13b, there is formed a cutout 14 that can be inserted into the hook 13b.
Then, after the two steel plates 24 and 25 are butted so that the engaging portion 13b of the one steel plate 25 is inserted into the defective portion 14 of the other steel plate 24, the both steel plates 24 and 25 are slid up and down to make each hook. The stopper 13b is fitted into the groove 13c and connected.
In the present embodiment, by continuously forming the wrapping portion 13a, it is possible to suppress or eliminate the generation of a gap between the connection portions after the connection of the steel plates 24 and 25, and to reduce the gap between the rolled steel plate and the existing steel plate. It is possible to suppress or prevent the leakage of the filler filled between the pillars.
In addition, the combination which formed the covering part 13a of each steel plate 24 and 25 intermittently, and formed the hook part 13b continuously may be sufficient.
Also, in the present embodiment, the construction method is the same as that of the above-described embodiment of the invention, and the description is omitted.
[0017]
【The invention's effect】
The present invention has the following effects.
<B> High strength can be assembled without using welding or bolting when assembling the rolled steel plate.
<B> Since a split steel plate of almost the same length as the existing pillar can be externally assembled from the side of the existing pillar, it is most suitable for reinforcing the existing pillar which has a limited sky.
<C> A rolled steel plate can be assembled by a simple operation of moving the attached divided steel plate vertically and fitting the joint. Therefore, the work time, labor, and construction cost required for winding the wound steel plate can be significantly reduced.
<D> Since the joint portion can be set in a tension state, rattling of the joint portion is eliminated, and all rolled steel plates can be firmly integrated.
<E> With the bolts screwed to the split steel plate, the verticality of the wound steel plate can be finely adjusted, and a tensile force can be applied to the joint portion.
<F> Since there is no joint in the vertical direction, not only the shear strength but also the bending strength of the existing structure can be enhanced.
<G> By forming one of the hooking part or the wrapping part that constitutes the joint part continuously and forming the other intermittently, it is possible to suppress the generation of a gap between the connecting parts after the joint part is connected or It is possible to suppress or prevent the leakage of the filler filling between the wound steel plate and the existing column.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a wound steel plate according to Embodiment 1 of the present invention. FIG. 2 is a partially omitted perspective view showing a connection structure of divided steel plates. FIG. 3 is a description of a method of reinforcing an existing column. Fig. 4 is a conceptual view showing a process until the existing column is covered with one of the divided steel plates. Fig. 4 is an explanatory view of a reinforcing method of the existing column, and shows a process until the other column is covered with the other divided steel plate. FIG. 5 is a partially omitted perspective view showing a connection structure in which joints of split steel plates are connected. FIG. 6 is an explanatory view of a method of reinforcing an existing column, and is a winding stand that is wound around the existing column. FIG. 7 is a conceptual diagram showing a process of temporarily receiving a steel plate and tensioning bolts. FIG. 7 is an explanatory view of a method of reinforcing an existing column, and illustrates a process of solidifying the existing column and a lower portion of a rolled steel plate. FIG. 8 is an enlarged cross-sectional view of a joint portion before a tensile force is introduced. FIG. 9 is an enlarged sectional view of a joint portion after a tensile force is introduced. FIG. 10 is a cross-sectional view of a rolled steel plate according to a second embodiment of the present invention using an intermediate plate. FIG. 11 is a description of a third embodiment of the present invention for suppressing or eliminating the generation of a gap between connecting portions. FIG. 12 is a cross-sectional view of the joint.

Claims (7)

In a rolled steel plate wound around the outer circumference of the existing pillar,
It consists of a plurality of split steel plates that have almost the same length as the entire length of the existing column,
On both end portions of each of the divided steel plates, joints that can be fitted to each other by sliding in the longitudinal direction of the divided steel plates are formed intermittently,
Rolled steel plate. In a rolled steel plate that is rolled up around the outer circumference of an existing column with a restricted sky,
A plurality of split steel plates exhibiting substantially the same length as the entire length of the existing column,
Presenting approximately the same length as the entire length of the existing column, and comprising a plurality of intermediate plates to block between the divided steel plates,
A joint portion that can be fitted to each other by sliding in the longitudinal direction of the plate body is formed intermittently on both end portions of each of the divided steel plate and the intermediate plate,
Rolled steel plate. In claim 1 or claim 2, the split steel plate is provided with a plurality of bolts for obtaining a reaction force from the existing column and fitting the joint portion in a tension state and finely adjusting the verticality of the plate. Characterized, rolled steel plate. In any one of claims 1 to 3, the joint portion is formed by forming a dovetail groove capable of fitting another hooking portion between the wrapping portion and the hooking portion, and the wrapping portion or A wound steel plate, wherein one of the hook portions is formed intermittently and the other is formed continuously. In a method of reinforcing an existing column, a steel plate is wound around the periphery of the existing column, and a filler is filled between the steel plate and the existing column to reinforce the column.
Using the wrapped steel sheet according to claim 1 or claim 2,
Each split steel plate or intermediate plate is abutted from the side of the existing pillar body and slid relatively up and down to connect and join together the joint portions,
How to reinforce existing columns. In a method of reinforcing an existing column, a steel plate is wound around the periphery of the existing column, and a filler is filled between the steel plate and the existing column to reinforce the column.
Using the wound steel plate according to claim 3,
Abutting each split steel plate or intermediate plate from the side of the existing column and sliding it relatively up and down to connect each joint,
The bolt is rotated to fit the joint in a tensioned state, and the verticality of the plate is finely adjusted.
How to reinforce existing columns. In a method of reinforcing an existing column, a steel plate is wound around the periphery of the existing column, and a filler is filled between the steel plate and the existing column to reinforce the column.
Using the rolled steel sheet according to claim 4,
Abutting each split steel plate or intermediate plate from the side of the existing column and sliding it relatively up and down to connect each joint,
The bolt is rotated to fit the joint in a tensioned state, and the verticality of the plate is finely adjusted.
How to reinforce existing columns.

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