JP6757604B2 - Abdominal joint structure - Google Patents

Description

The present invention relates to an abdominal joint structure for forming a corner portion by joining directly butted abdominal ridges on the same plane that stiffens the retaining wall.

Conventionally, in the girder type support, which is one of the support works to stiffen the retaining wall, the outside of multiple framed abdomen is brought into contact with the retaining wall, and the cutting beam and flint are placed inside. By installing and reinforcing the framework, the retaining wall is prevented from deforming inward. Even within the framework, the corners where the abdomen is joined at right angles generate a large bending moment when excessive earth pressure acts from the surrounding ground to the retaining wall, so it is necessary to ensure high rigidity that can withstand this. is there.

For example, in Patent Document 1, an L-shaped joining member is inserted between the ends of the raised parts arranged orthogonally on the same plane, and the raised parts are raised by bolts through the joint member. By connecting the above and installing a flint on the inner corner side, rigidity is secured at the corner.

Japanese Unexamined Patent Publication No. 2001-262560

In the above configuration, by using the L-shaped joining member, the abdominal ridges located at right angles can be joined in the same plane shape by using bolts, so that the joining structure can be simplified. However, since the L-shaped joint member is composed of a member having a cross section similar to that of the abdomen, the weight and the outer shape are both large, and the installation work becomes complicated. In addition, since the joining member needs to be manufactured as a dedicated part, the cost tends to increase. Further, since the flint is arranged so as to occupy a part of the opening inside the framework composed of the abdomen, it tends to be an obstacle when excavation work is performed.

The present invention has been made in view of such a problem, and its main purpose is to secure a wide area without obstacles in the sky in the work space in the retaining wall, which is inexpensive and has good workability. It is to provide an abdominal joint structure.

In order to achieve such an object, the raised joint structure of the present invention is a raised joint structure that stiffens the retaining wall, and one end of the raised portion is a flange of the other raised portion. A corner portion is formed by directly abutting the corner portion and joining the corner portion. In the corner portion, an L-shaped tensile force bearing member arranged so as to cover the protruding corner portion is formed by a high-strength bolt. The abdomen is joined to each of the abdomen, and the compressive force bearing member arranged at the inside corner and in contact with the abdomen is joined to the abdomen of each flange with a high-strength bolt. A stiffener is installed in the region sandwiched between the tensile force bearing member and the compressive force bearing member, and a backfilling material is installed between the retaining wall and the corner portion. It is characterized by.

According to the above-described abdominal joint structure of the present invention, by installing the tensile force bearing member, the compressive force bearing member, and the stiffener at appropriate positions in the corners, these complement each other and an external force acts. It is possible to secure a proof stress and rigidity at the corner portion so that the bending moment and the shearing force generated by the above can be smoothly transmitted to each other. As a result, since it is not necessary to install a flint material in the inner corner of the corner, it is possible to secure a work space without obstacles in the sky above the corner in the retaining wall.

In addition, since the backfilling material is installed between the retaining wall and the corner, an external force in the direction of pressing the abdomen acts on the tensile force bearing member that covers the protruding corner of the corner, so that the tensile force is applied. It is possible to stiffen the bearing member.

Further, since the orthogonal abdomen can be directly butted and joined, it is not necessary to use a conventional joining member having a large weight and outer shape between the orthogonal abdomen, which greatly improves workability. It becomes possible.

In addition, for the tensile force bearing member, compressive force bearing member, and stiffener, existing members commonly used when constructing a steel-framed temporary structure can be applied without making special equipment. Therefore, all of these members can be reused, and a temporary structure can be constructed inexpensively and easily.

According to the present invention, by installing the tensile force bearing member, the compressive force bearing member, and the stiffener at appropriate positions in the corner portion, it is inexpensive and easy to work, and the corner portion in which the orthogonal abdomen is directly butted is formed. Since it can be formed into a joint structure that can be regarded as a rigid joint, it is possible to secure a work space without obstacles in the sky above the retaining wall without the need for flint materials installed in the inner corners of the corners. Become.

It is a figure which shows the joint structure of the abdomen in the corner part of this invention. It is a figure which shows the compressive force bearing member of this invention. It shows the result of confirming the proof stress of the abdominal joint structure in the corner part of this invention. It shows the result of confirming the rigidity of the abdominal joint structure in the corner part of this invention. It is a figure which shows the other example of the joint structure of the abdomen in the corner part of this invention.

The mountain retaining support of the present invention has a structure in which the corners where the abdominal ridges arranged at right angles are directly abutted and joined can be regarded as a rigid joint, and a flint material is not required. The abdominal joint structure of the present invention will be described below with reference to FIGS. 1 to 4.

As shown in FIG. 1, the raised 3a and 3b constituting the retaining support are so-called mountain retainers in which the end plate 33 is installed on the end face of the H-shaped steel provided with the web 31 and the pair of flanges 32. It is made of wood, and a plurality of webs 31 are installed along the inner wall surface of the retaining wall 7 in a horizontal state. These raised 3a and 3b are formed by joining the adjacent raised 3a and 3b in the same plane to form a framework, and the retaining wall 7 is provided together with a girder (not shown) installed inside the raised walls 7 to reinforce the framework. It prevents it from deforming inward.

Such raised 3a and 3b are arranged orthogonally by directly abutting the end plate 33 of one raised 3b against the flange 32 of the other raised 3a to form a corner portion 4. There is. The joint structure of the abdominal raising 3a and 3b at the corner portion 4 includes the tensile force bearing member 1 installed on the protruding corner side, the compressive force bearing member 2 installed on the inner corner portion, and the abdominal raising 3a. The stiffener 34 provided for 3b is provided.

The tensile force bearing member 1 is formed by welding and fixing a strip-shaped steel plate having the same width as the flanges 32 of the raised 3a and 3b so as to form an L shape, and has predetermined intervals in the length direction and the width direction. A bolt hole is provided. In the present embodiment, two splice plates, which are generally used when joining steel members with high-strength bolts, are welded as the tensile force bearing member 1. In addition, both the flange 32 of the raised 3a and the flange 32 of the raised 3b located on the protruding corner side of the corner portion 4 have a plurality of arrangement intervals having the same arrangement intervals as the bolt holes provided in the tensile force bearing member 1. Bolt holes are provided.

Then, the tensile force bearing member 1 is arranged so as to cover the protruding corner portion of the corner portion 4, and by inserting and fastening the high-strength bolt 5 through the bolt holes of each other, the flange 32 of the abdominal portion 3a and the end plate are fastened. It is joined to the raised 3a and 3b so as to be in contact with the flange 32 of the raised 3b and the raised 3b in a plane.

The tensile force bearing member 1 is not limited to the above L-shape, as long as it is a member capable of smoothly transmitting the tensile force generated between the raised abdomen 3a and 3b to be joined. Any shape or material may be used. However, if an L-shaped member is adopted as the tensile force bearing member 1, the tensile force bearing member 1 comes into contact with the flange 32 and the end plate 33 of the raised 3a in a wide range. As a result, a large number of high-strength bolts 5 used for joining the abdominal raising 3a and 3b can be used, and a large frictional force can be expected, so that the tensile force can be transmitted more efficiently.

Further, as shown in FIG. 2, the compressive force bearing member 2 is arranged orthogonally to a pair of abutting plates 21 arranged orthogonally in an upright state and a pair of abutting plates 21 so as to connect them. It is composed of three connecting plates 22. The pair of contact plates 21 are made of steel plates that are raised in the height direction and have the same size as the width of the flanges 32 of 3a and 3b, and are provided with bolt holes at predetermined intervals in the longitudinal direction. There is. The three connecting plates 22 are composed of substantially triangular steel plates arranged in parallel at intervals in the height direction of the contact plates 21.

In this embodiment, a corner block, which is generally used for entering a corner when the steel frame members are arranged orthogonally to the compressive force bearing member 2, is adopted. Further, each of the flanges 32 of the raised 3a and 3b located on the entrance side of the corner portion 4 is provided with a plurality of bolt holes at the same arrangement interval as the bolt holes provided in the pair of contact plates 21. There is.

In the compression force bearing member 2 having such a configuration, as shown in FIG. 1, each of the pair of contact plates 21 rises up and comes into contact with each of the flanges 32 of 3a and 3b at the inside corner of the corner portion 4, and 3 The connecting plate 22 located at the center of the connecting plates 22 is arranged so as to be located at a height at which the connecting plate 22 is raised and forms the same plane as the web 31 of 3a and 3b. Then, by inserting and fastening the high-strength bolt 5 through the bolt holes of the flanges 32 and 32 of the abdomen 3a and 3b with the pair of abutting plates 21, the compressive force bearing member 2 is abdominalized 3a. It is joined so as to be sandwiched between it and 3b.

The compressive force bearing member 2 is not limited to a member having a substantially triangular prism shape such as a corner block. A member having a pair of abutting plates 21 and at least one connecting plate 22 connecting the abutting plates 21 and capable of smoothly transmitting the compressive force generated between the raised abdomen 3a and 3b to be joined. Any shape or material may be used.

Further, as shown in FIG. 1, the stiffener 34 is composed of a square tubular member having a height corresponding to 1/2 of the width of the flange 32 in the raised 3a and 3b, and has four side surfaces. One of the two opposing surfaces has a length similar to the height of the web 31 of the raised 3a and 3b. As a result, when the stiffener 34 is raised and placed between the pair of flanges 32 of each of the 3a and 3b, the other two opposing surfaces come into contact with the inner surfaces of the pair of flanges 32. In the present embodiment, bolt holes are provided on the other two opposing surfaces that come into contact with each of the pair of flanges 32 of the raised 3a and 3b so that they can be attached to and detached from the raised 3a and 3b. It is provided.

The stiffener 34 having such a configuration is arranged so that the opening surface is parallel to the web 31 in the range sandwiched between the tensile force bearing member 1 and the compressive force bearing member 2 in the raised abdomen 3a and 3b. It is installed with respect to the flange 32 via bolts. In the present embodiment, the high-strength bolt 5 used for joining the tensile force-bearing member 1 and the compressive force-bearing member 2 is also used for installing the stiffener 34, but the installation method is not necessarily the same. It is not limited.

Further, in the present embodiment, three stiffeners 34 are installed in each of the raised abdomen 3a and 3b, but the quantity thereof may be appropriately changed as needed. Further, when the stiffener 34 is arranged at the position farthest from the inner corner of the corner portion 4 in the range sandwiched between the tensile force bearing member 1 and the compressive force bearing member 2, the stiffener 34 is efficiently raised 3a. 3b can be stiffened.

In the joint structure of the raised 3a and 3b at the corner portion 4 having the above-described configuration, for example, as shown in FIG. 1, when a clockwise bending moment M and a shearing force Q are generated at the end of one raised 3b. , These are smoothly transmitted to the other abdomen 3a. That is, the tensile force due to the bending moment M is transmitted to the other abdominal raising 3a via the tensile force bearing member 1, and the compressive force due to the bending moment M is transmitted to the other via the compressive force bearing member 2 and the stiffener 34. It is transmitted to the abdomen 3a.

Further, the shearing force Q generated at the end of one of the raised 3b is raised with the contact plate 21 of the compressive force bearing member 2 bolted to the other raised 3a with a high-strength bolt 5. By bolting the shear 3a to the flange 32, it is transmitted to the other raised 3a.

In this way, by arranging the tensile force bearing member 1, the compressive force bearing member 2, and the stiffener 34 at appropriate positions of the corner portion 4, they complement each other and the bending moment M generated by the action of the external force is applied. And, the proof stress and rigidity enough to smoothly transmit the shearing force Q between the abdomen 3a and 3b can be secured in the corner portion 4. Therefore, without using welded joints, it is possible to perform a rational design by regarding the corner portion 4 in which the raised parts 3a and 3b are directly abutted and joined by the high-strength bolt 5 as a rigid joint.

A laboratory experiment was conducted on a corner portion 4 formed by joining a tensile force bearing member 1, a compressive force bearing member 2, and a stiffener 34 to the above-mentioned abdominal raising 3a and 3b using a high force bolt 5. Was carried out to confirm its proof stress and rigidity.

First, as shown in FIG. 3A, one abdominal uplift 3b is arranged so as to be horizontal, and the other abdominal uplift 3a is arranged so as to be vertical, and then one abdominal uplift 3b is placed. The corner portion 4 is formed by abutting against the other raised abdomen 3a and joining by the means described above. Then, the other abdomen 3a is supported on the ground surface via a pin, and the one abdomen 3b is connected to the loading device 6 via a pin, and the abdomen 3b is connected to the one abdomen 3b from the loading device 6. Load the axial load. After that, when the corner portion 4 reaches the final state, the loading is stopped.

On the other hand, a corner portion 4 is prepared in advance in which the above-mentioned raised parts 3a and 3b are joined by welding to form a rigid joint, and the yield load is calculated using the above-mentioned loading device 6. In the present embodiment, it has been found that when an H steel material having a size of 350 mm is used for the raised abdomen 3a and 3b to be welded, the yield occurs when the size exceeds 195 kN.

Therefore, in this experiment, the design load is set to 195 kN, and when the corner portion 4 in the present embodiment yields after exceeding 195 kN, it is assumed that the bearing capacity required to be regarded as a rigid joint is provided. It was decided to judge. Then, looking at FIG. 3B, it can be seen that the yield occurs when the load exceeds 200 kN, and the final load is about 400 kN.

Next, as shown in FIG. 4A, 12 strain gauges (T1) are in contact with the end plate 33 of the raised 3a and the flange 32 of the raised 3b in the tensile force bearing member 1. ~ T9, X1 to X3) are attached, and the state of strain generated in the tensile force bearing member 1 when 195 kN set as the design load is loaded is confirmed.

The inventors have obtained the finding that the strain of the base material used for the tensile force bearing member 1 when reaching the design yield point is 1050 μ. Therefore, in this experiment, when a design load of 195 kN is loaded on the corner portion 4, the rigidity required to consider the corner portion 4 as a rigid joint is provided when the strain of the tensile force bearing member 1 does not exceed 1050 μ. It was decided that it was.

As shown in FIG. 4B, although the strain slightly exceeds 1050μ at the positions of T8 and X3, it is within 1050μ as a whole. Although not adopted in the experiment, in the present embodiment, as shown in FIG. 1, the backfill material 8 is filled between the abdominal raising 3a and 3b including the corner portion 4 and the retaining wall 7. There is.

The backfilling material 8 not only has a function of efficiently transmitting the earth pressure acting on the retaining wall 7 to the abdomen raising 3 and also functions as a member for stiffening the tensile force bearing member 1. That is, by inserting the backfill material 8 between the corner portion 4 and the retaining wall 7, the tensile force bearing member 1 that covers the protruding corner portion of the corner portion 4 from the ground via the backfill material 8 An external force in the direction of raising the abdomen and pressing 3a and 3b acts. As a result, the tensile force bearing member 1 is constrained by the raised 3a and 3b and the backfilling member 8, so that the amount of strain can be significantly reduced.

As described above, since the corner portion 4 provided with the backfill material 8 has the same proof stress and rigidity as the case where the raised 3a and 3b are rigidly joined by welding, the raised 3a and 3b are formed. The joint structure of the raised abdomen 3a and 3b at the corners 4 butted at right angles can be regarded as a rigid joint. Therefore, it is not necessary to install a flint material in the inner corner portion of the corner portion 4, and it is possible to secure a work space in the retaining wall 7 with no obstacles above the corner portion 4.

Further, in the joining structure of the raised 3a and 3b at the corner portion 4, since the orthogonal raised 3a and 3b are directly butted and joined, a dedicated part such as a conventional joining member having a large weight and external shape is used. It is not necessary to manufacture and insert the product, and the workability can be greatly improved.

In addition, it is generally used when constructing a steel-framed temporary structure such as a splice plate for the tensile force bearing member 1, a corner piece for the compressive force bearing member 2, and an abdominal stiffener for the stiffener 34. Existing parts can be adopted. Since all of these members can be reused, it is possible to construct the corner portion 4 inexpensively and easily.

The angry joint structure of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

In the present embodiment, the size of the pair of contact surfaces 21 in the compressive force bearing member 2 is the same, but the size is not necessarily limited to this, and for example, the abdominal ridge 3a forming the corner portion 4 Of 3b, the length of the contact surface 21 in contact with one of the raised abdomen 3b may be increased.

Further, in the present embodiment, concrete is filled as the backfilling material 8, but the present invention is not necessarily limited to this, and means such as inserting a backfilling block, which are generally used in the pile support work. If there is, any backfilling material 8 may be adopted.

Further, in the present embodiment, as shown in FIG. 1, the joint structure of the corner portion 4 in which the abdomen raised 3a and 3b are orthogonally butted is adopted for the retaining wall made of steel sheet pile, but the present invention is not necessarily limited to this. It's not something to do. For example, as shown in FIG. 5, if it is used for a retaining wall by the main pile / horizontal sheet pile method, or if the abdominal raising 3a and 3b are butted at right angles, it is adopted for any retaining wall. You may.

1 Tensile force bearing member 2 Compressive force bearing member 3a Raised 3b Raised 31 Web 32 Flange 33 End plate 34 Stiffener 4 Corner 5 High-strength bolt 6 Loading device 7 Retaining wall 8 Backfilling material

Claims (1)

It is an abdominal joint structure that stiffens the retaining wall.
A corner portion is formed by directly abutting one end of the abdomen to the flange of the other abdomen and then joining them.
In the corner portion, an L-shaped tensile force bearing member arranged so as to cover the protruding corner portion is raised by a high-strength bolt and joined to each of them, and is arranged at the inside corner portion to raise the abdomen. The compressive force bearing members in contact with each of the above-mentioned raised parts are joined to the respective flanges with high-strength bolts.
A stiffener is installed in the region sandwiched between the tensile force bearing member and the compressive force bearing member of each of the raised abdomen, and a backfill material is installed between the retaining wall and the corner portion. An abdominal joint structure characterized by the fact that.