JP6986764B2 - How to connect lug screw bolts - Google Patents

Description

The present invention relates to a method for connecting a lag screw bolt suitable for connecting a cross laminated board and a steel material in a wood-steel hybrid structure in which a cross laminated board (CLT) instead of an RC structure or an S structure is connected to a steel material.

The wood-steel hybrid structure, which uses wooden orthogonal laminated boards and steel materials, has the same strength as RC construction and is several steps lighter than RC construction, so it can be used for mid-to-high-rise buildings and stadiums, which was not possible until now. Is possible. Overseas, high-rise buildings with wood-steel hybrid structures using orthogonal laminated boards have also been completed.

When constructing a building-type building with such a wood-steel hybrid structure, the connecting structure between the wooden orthogonal laminated wood and the steel material is extremely important. Therefore, as shown in FIG. 7, a headless stud 10 is welded to the upper surface of the steel material P, a through hole Q3 through which the stud 10 is penetrated is provided in the orthogonal laminated plate Q, and the through hole Q3 is provided in the stud 10. At the same time, a connecting means is adopted in which the orthogonal laminated wood plate Q is dropped, the gap between the stud 10 and the through hole Q3 is filled with the epoxy resin 11, and the orthogonal laminated wood plate Q and the steel material P are integrated.

However, there is a problem in using an epoxy resin, and there is a demand for a method of connecting without using the epoxy resin. That is, in order to fill the epoxy resin, a lot of labor and construction period are required, such as a curing work, a filling work, and a waiting time until the filled epoxy resin is cured. Moreover, the epoxy resin is expensive, which has led to an increase in construction cost.

Therefore, a connecting means using the lug screw bolt 20 shown in FIG. 8 instead of the stud to be welded to the steel material has been studied. The lug screw bolt 20 is a special bolt in which a female screw for connecting the connecting bolt R is formed on the rear end side of the bolt, and the connecting bolt R connects the orthogonal laminated plate Q to the steel material P.

That is, a pilot hole Q1 is formed on the connecting end side of the orthogonal laminated plate Q, and a lug screw bolt 20 is embedded in the pilot hole Q1. On the other hand, a bolt insertion hole is opened in the connecting portion of the steel material P, and the connecting bolt R through the bolt insertion hole from the lower surface of the steel material P and the lug screw bolt 20 of the orthogonal laminated plate Q on the upper surface of the steel material P are screwed together. It is a means for connecting the orthogonal laminated plate Q to the steel material P. This connecting means makes it possible to reduce the amount of epoxy resin used.

On the other hand, the conventional lug screw bolts that connect wood to each other have a structure in which a tightening tool is attached to the bolt head and screwed into a pilot hole of wood (Patent Documents 1 and 2).

The lug screw bolt described in Patent Document 1 is configured to reduce the screwing force into a pilot hole of wood and increase the pull-out resistance. That is, a taper is formed at the tip of the lug screw bolt, and a notch is formed at the outer periphery of the tip of the screw thread.

The lug screw bolt described in Patent Document 2 relates to a configuration and an embedding method that secures the bond strength between woods and enables straight and easy screwing into a wood member. As this embedding method, a step of drilling a pilot hole having a diameter smaller than the outer diameter of the shaft portion in the wood member, a step of filling the pilot hole with an adhesive, and a step of screwing the joining metal fitting into the pilot hole filled with the adhesive. An embedding method with a process is shown.

Japanese Patent No. 4462612 Japanese Unexamined Patent Publication No. 2007-77629

A conventional lug screw bolt that connects wood to each other has a structure in which a tightening tool is attached to the head and the lug screw bolt is screwed into a pilot hole of the wood with this tightening tool. Therefore, it is necessary to preliminarily form a pilot hole (Patent Document 1) having a length to be embedded up to the bolt head and a recess called counterbore (Patent Document 2) at the connecting end portion of the wood.

In particular, since the lag screw bolt of Patent Document 2 is configured to fill the prepared hole with an adhesive, the curing work and filling work required for filling the adhesive, and the time until the filled adhesive is cured. It takes a lot of time and effort and construction period.

On the other hand, in the wood-steel hybrid structure, even when the orthogonal laminated plate Q and the steel material P are connected by a special lag screw bolt 20, the counterbore Q2 in which the head of the lag screw bolt 20 is embedded in the orthogonal laminated plate Q Formation was required (see FIG. 8). Therefore, if the recess of the counterbore Q2 becomes deep at the connecting end of the orthogonal laminated board Q, it becomes difficult for the tightening force between the lug screw bolt 20 and the connecting bolt R to be transmitted to the orthogonal laminated board Q. Needed to be filled.

Therefore, when the lug screw bolt 20 shown in FIG. 8 is used, the amount of the epoxy resin used is extremely smaller than that of the connecting means using the stud 10 shown in FIG. 7, so that the construction cost can be reduced. However, even if the amount used is small, it still takes a lot of time and effort, such as the curing work and filling work required to fill the epoxy resin, and the time it takes for the filled epoxy resin to cure. ..

Therefore, the present invention has been devised to solve the above-mentioned problems. In a wood-steel hybrid structure in which a steel material and an orthogonal laminated wood are connected by a connecting bolt, no epoxy resin is required, and the steel material and the steel material are used. An object of the present invention is to provide a method for connecting a lug screw bolt that can be easily connected to an orthogonal laminated board with sufficient strength.

In order to achieve the above object, the first means of the present invention is to connect a steel material P for a wood-steel hybrid structure and an orthogonal laminated plate Q constituting a wooden floor material with a lug screw bolt L and a high-strength bolt. In the method of connecting lug screw bolts, the lug screw bolt L has a screw thread 2 extending from the tip end side to the rear end portion of the bolt body 1 embedded in the prepared hole Q1 drilled in the orthogonal assembly plate Q. Using a lug screw bolt L for screwing a high-strength bolt connecting bolt R to the female screw portion 3 formed at the rear end of the bolt body 1, the size of the prepared hole Q1 is set to the screw of the lug screw bolt L. An attachment 30 with a flange 31 formed of a bolt having a diameter smaller than the diameter of the female screw portion 3 is screwed to the female screw portion 3 of the lug screw bolt L, which is formed to have the same diameter as the valley diameter of the ridge 2. A tightening tool T is attached to the attachment 30, and a lug screw bolt L is screwed in until the flange 31 abuts on the connecting end of the orthogonal assembly plate Q, and from the lug screw bolt L screwed into the prepared hole Q1 to the rear end. After removing the attachment 30 , the steel material P and the lug screw bolt L are connected by the connecting bolt R at the position where the rear end portion of the lug screw bolt L and the connecting end portion of the orthogonal assembly plate Q are in contact with the steel material P. be.

According to the first aspect of the present invention, a screw thread 2 to be screwed into a prepared hole Q1 opened inward from a connecting end portion of the orthogonal laminated plate Q is formed from the side surface of the rear end portion of the bolt body 1 to the tip end portion side, and the screw thread 2 is formed. connecting the valley diameter of the thread 2, by forming so as to match the dimensions of the prepared hole Q1 of the quadrature assembly plate Q, the quadrature assembly plate Q and steel P of "wood-steel hybrid structure" It was possible to securely connect with only the connecting bolt R without using any adhesive such as epoxy resin.

Therefore, in the wood-steel hybrid structure, it has become possible to connect the orthogonal laminated board Q and the steel material P without using any epoxy resin. As a result, we succeeded in eliminating all the labor and construction period required for filling the epoxy resin, such as the curing work and filling work, and the time required for the filled epoxy resin to cure, resulting in an expensive epoxy resin. Since it is not used, the construction cost can be reduced. For these reasons, the number of processes and the latter period when constructing a building-type building with a wood-steel hybrid structure has been significantly reduced, and it has become an extremely important member that supports the innovative technology of the wood-steel hybrid structure.

Moreover , by forming the valley diameter dimension of the screw thread 2 of the bolt body 1 to match the dimension of the pilot hole Q1 of the orthogonal laminated wood plate Q, the integration of the bolt main body 1 and the orthogonal laminated wood plate Q is the most solid. Therefore, it has become possible to firmly connect the orthogonal laminated board Q and the steel material P in the "wood / steel hybrid structure".

The attachment 30 formed of the flanged bolt is screwed to the female screw portion 3 of the lug screw bolt L before being screwed into the prepared hole Q1, and the tightening tool T is attached to the head of the attachment 30 to form an orthogonal assembly plate. By screwing the lug screw bolt L until the flange 31 comes into contact with the connecting end of the Q, the rear end 4 of the bolt body 1 and the connecting end of the orthogonal assembly plate Q can be accurately and easily matched.

Moreover, since the attachment 30 is removed from the lug screw bolt L screwed into the prepared hole Q1 and then the steel material P and the orthogonal laminated plate Q are connected by the connecting bolt R, the connecting work is simplified and the connecting work is extremely rational. become.

Further , by forming the pilot hole Q1 of the orthogonal laminated plate Q to have the same diameter as the valley diameter of the screw thread 2 of the lug screw bolt L, the adhesion between the orthogonal laminated plate Q and the lug screw bolt L is improved. , Succeeded in obtaining stable connection strength in "wood / steel hybrid structure".

It is a side view which shows one Example of the bolt of this invention. It is a rear end view which shows one Example of the bolt of this invention. It is a side sectional view which shows the connecting work of the bolt of this invention. It is a side sectional view which shows the state which the bolt of this invention is fixed to the orthogonal laminated board. It is a side sectional view which shows the state which connected the steel material and the orthogonal laminated wood in this invention. It is a side sectional view which connected the orthogonal laminated wood plates to each other in this invention. It is a side sectional view which connected the orthogonal laminated plate to the steel frame beam with the conventional stud. It is a side sectional view which shows the use example of the conventional lug screw bolt.

The present invention will be described with reference to the illustrated examples. The lag screw bolt L of the present invention is used for a wood-steel hybrid structure. For example, when constructing a building type building, a steel material P such as a steel beam and an orthogonal laminated plate Q are referred to as the lag screw bolt L. It is fixed with a connecting bolt R.

The structure of the lug screw bolt L is such that a screw thread 2 is formed on the side surface from the tip end side to the rear end portion 4 of the cylindrical bolt body 1 and has a so-called all-screw bolt shape (so-called all-screw bolt shape). See Figure 1). Further, a female screw portion 3 is formed at the rear end portion of the bolt body 1. Then, the bolt body 1 is screwed into the prepared hole Q1 opened in the connecting end portion of the orthogonal laminated plate Q in advance. As the material of the bolt body 1, it is preferable to use a bolt having high strength.

When screwing the bolt body 1 into the prepared hole Q1, until the position of the rear end 4 of the bolt body 1 matches the position of the connecting end of the orthogonal laminated plate Q, that is, the position of the open end of the prepared hole Q1. Screw it into the pilot hole Q1 (see FIG. 4). In the wood-steel hybrid structure, in order to connect the orthogonal laminated plate Q to the steel material P, the connecting bolt R penetrating the steel material P is screwed to the female screw portion 3 of the bolt body 1 to be orthogonally assembled to the steel material P. It is a structure that connects to the plate Q (see FIG. 5).

According to the experiment, when the steel material P and the orthogonal laminated plate Q are connected, the rear end portion of the bolt body 1 and the connecting end portion of the orthogonal laminated wood plate Q are connected so as to be fixed at a position in contact with the steel material P. It was found that the integration of the bolt body 1, the orthogonal laminated plate Q, and the steel material P became the most rigid, and sufficient connection strength could be obtained without using an epoxy resin (see FIG. 5). That is, the position of the screw thread 2 of the rear end portion 4 of the bolt body 1 coincides with the position of the open end portion of the prepared hole Q1 of the orthogonal laminated plate Q connecting end portion, and is in a connected state in contact with the steel material P.

When a punching shear test of the bolt body 1 screwed into the prepared hole Q1 was performed under these connection conditions, high shear strength was obtained for all of the strong shaft, the weak shaft, and the grain. Therefore, the position where the position of the rear end portion 4 of the bolt main body 1 and the position of the prepared hole Q1 end portion of the connecting end portion of the orthogonal laminated plate Q coincides with each other is set as a fixed position of the bolt main body 1 screwed into the prepared hole Q1.

On the other hand, on the rear end side of the bolt body 1, a female screw portion 3 for screwing the connecting bolt R is formed (see FIGS. 1 and 2). By screwing the connecting bolt R penetrating the steel material P to the female screw portion 3, the steel material P and the orthogonal laminated plate Q are connected (see FIG. 5).

The bolt body 1 shown in the figure has a taper 5 on the tip end side to facilitate insertion into the prepared hole Q1 (see FIG. 1). Further, the screw thread 2 formed on the tip end side of the bolt body 1 is formed up to the taper 5.

The method of connecting the lag screw bolt L of the present invention is as follows. First, an attachment 30 for connection formed by a bolt with a flange is prepared (see FIG. 3). Next, the attachment 30 is screwed to the female screw portion 3 of the lug screw bolt L before being screwed into the prepared hole Q1. Further, a tightening tool T is attached to the head of the attachment 30 in this state, and the lug screw bolt L is screwed into the prepared hole Q1 until the flange 31 comes into contact with the connecting end of the orthogonal laminated plate Q (see FIG. 3). ..

Next, when the attachment 30 is removed from the lug screw bolt L screwed into the prepared hole Q1, the position of the rear end portion 4 of the bolt body 1 and the position of the connecting end portion of the orthogonal laminated plate Q coincide with each other by the action of the flange 31. (See Fig. 4). Finally, after removing the attachment 30 from the lug screw bolt L screwed into the prepared hole Q1, the steel material P and the orthogonal laminated plate Q are connected by the connecting bolt R (see FIG. 5). As the attachment 30 used at this time, a bolt with a flange having a diameter slightly smaller than that of the female screw portion 3 is used in order to make it easy to remove the bolt body 1 from the female screw portion 3 after screwing the bolt body 1 into the prepared hole Q1.

The lug screw bolt L of the present invention is a member for connecting the orthogonal laminated plate Q used in the wood-steel hybrid structure to the steel material P in particular. Therefore, when a pilot hole Q1 for further enhancing the connecting strength of the orthogonal laminated plate Q was studied, when the size of the prepared hole Q1 was formed to be the same as the valley diameter of the thread 2 of the lug screw bolt L, it was orthogonal. The adhesion between the laminated plate Q and the lug screw bolt L was improved, and stable strength between the orthogonal laminated plate Q and the steel material P was obtained.

For example, when the outer diameter of the pilot hole of the conventional lug screw bolt that connects the timbers is M30 and the valley diameter of the screw thread 2 is 25 mm in diameter, a pilot hole with a diameter of 26 mm is considered to be good for construction. On the other hand, in the lug screw bolt L of the present invention, when the valley diameter of the screw thread 2 is 25 mm in diameter, the diameter of the prepared hole Q1 is also 25 mm in diameter. According to the tensile test of the lug screw bolt L screwed into the prepared hole Q1 under this condition, high connection strength was obtained for all of the strong shaft, the weak shaft, and the grain, and there was no problem of screwing work.

In the illustrated construction example, the steel beam of the wood-steel hybrid structure is made of steel P, and the orthogonal laminated board Q used as the floor material is connected to this steel beam (see FIG. 5). Further, as another construction method, it is also possible to connect the orthogonal laminated boards Q as flooring materials (see FIG. 6).

As shown in FIG. 6, in order to connect the floor materials of the orthogonal laminated boards Q to each other, the connecting steel plate M is used as the steel material P. That is, a pilot hole Q1 for the lug screw bolt L and a counterbore Q2 for embedding the connecting steel plate M to be bridged between the orthogonal laminated plates Q are formed at each connecting portion between the orthogonal laminated plates Q. Then, the lug screw bolt L is screwed into each prepared hole Q1.

Next, the connecting steel plate M is arranged at the bottom of the counterbore Q2, and the connecting steel plate M is bridged over each lug screw bolt L and connected by the connecting bolt R (see FIG. 6). At this time, the connecting end of the orthogonal laminated plate Q becomes the bottom of the counterbore Q2 in contact with the connecting steel plate M. As described above, the lug screw bolt L can be used for each connecting portion of the orthogonal laminated plate Q of the wood / steel hybrid structure. Further, the lag screw bolt L of the present invention can be used not only for a wood-steel hybrid structure but also for any construction in which a steel material P and an orthogonal laminated plate Q are connected by a connecting bolt R.

The structure, dimensions, materials, etc. of the bolt of the present invention are not limited to the illustrated examples, and can be arbitrarily changed without changing the gist of the present invention.

P Steel Q Orthogonal assembly plate Q1 Pilot hole Q2 Counterbore Q3 Through hole R Connecting bolt S Washer T Tightening tool L Lag screw bolt M Connecting steel plate 1 Bolt body 2 Thread 3 Female thread 4 Rear end 5 Tapered 10 Stud 11 Epoxy resin 20 Lag screw bolt 30 Attachment 31 Flange

Claims (1)

It is a method of connecting lag screw bolts that connects steel materials for wood / steel hybrid structures and orthogonal laminated boards that make up wooden floor materials with lag screw bolts and high-strength bolts .
The lug screw bolt has a thread extending from the tip end side to the rear end portion of the bolt body embedded in the prepared hole drilled in the orthogonal assembly plate, and is formed on the female screw portion formed at the rear end portion of the bolt body. Use lug screw bolts to screw connecting bolts made of high-strength bolts,
The size of the prepared hole is formed to be the same as the valley diameter of the thread of the lug screw bolt, and the attachment with a flange formed on the female thread part of the lug screw bolt with a bolt having a diameter smaller than the diameter of the female thread part. Screwed in
A tightening tool is attached to the attachment, and lug screw bolts are screwed in until the flange abuts on the connecting end of the orthogonal laminated plate.
After removing the attachment from the lug screw bolt screwed into the pilot hole to the rear end , connect the steel and lug screw bolt at the position where the rear end of the lug screw bolt and the connecting end of the orthogonal laminated plate are in contact with the steel. A method of connecting lug screw bolts, which is characterized by connecting with bolts.

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