JP3027931B2 - Prestressed laminated timber beam and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-strength laminated timber, and more particularly to a prestressed laminated timber beam .

[0002]

2. Description of the Related Art
For concrete structures, prestressed concrete is prestressed to increase its strength. Is used for various concrete structures including bridges. On the other hand, in response to the recent spread of concrete structures, wooden structures such as wooden bridges have been adopted as structures suitable for excellent natural environment and important cultural properties since ancient times. . However, the strength of the wooden structure was not sufficient, so that a structure receiving a high load could not be constructed of a wooden structure. In addition, although the amount of wood production is on a declining trend, the amount of particularly excellent wood produced is decreasing, and effective utilization of ordinary wood that cannot be used as a structural material is required. Therefore, lumber is used as a sawn board having a predetermined size (lamina having a thickness of 2.5 to 3.
It has been attempted to use a laminated wood manufactured by making a 5 cm replacement board) or small squared wood, drying it to a moisture content of 8 to 12%, and polymerizing and bonding them with their fiber directions aligned in the longitudinal direction. This glued lumber is an excellent lumber with less cracking and skew than the original material (wood). Even such laminated materials have the following problems in the joining (joining) technique of members. . Large loads cannot be transmitted to wooden joints and connections. . Big finger joint (BJF joint)
As for, careful humidity control and construction control are necessary, and there remains uncertainty about the reliability of the adhesive effect. When glued laminated timber is applied to a large beam member, it is required that the entire strength of the member be transmitted to the joint, but due to the above-mentioned problem, the effective transmission means is still required. Is not provided.

[0003]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventor has developed a prestressed laminated timber beam which can construct a high-strength wooden structure, and has accomplished the present invention. Was. That is, the present invention provides: (1) a laminated wood having a through-hole extending over the entire length in the longitudinal direction.
Are extended in abutment in series, thereby forming
Pre-stressed by tendon in the open communication slot
It is laid in tension in a state and forms a long high-strength laminated wood
A girder made of prestressed glulam. (2) Contact the contact surface where a plurality of glulams are in contact in series
According to claim 1, wherein the wear agent layer is characterized by comprising interposed
Prestressed laminated timber beams. (3) Outer periphery of the part where a plurality of glulams abut in series
The length of the prestressed laminated timber according to claim 1 or 2 , wherein the portion is wound by an auxiliary tool such as a square tubular body.
Beams . (4) A laminated wood having a through-hole extending over the entire length in the longitudinal direction
A plurality of abutting in series to extend, thereby forming
Insert the tendon into the communicating long hole, and then
Applying stress to make long, high-strength glulam
A method of manufacturing prestressed glued laminated timber beams. (5) Adhesion to the contact surface where a plurality of glulams are in contact in series
Pres claim 4, wherein interposing the adhesive layer
Method of manufacturing long beams made of stressed glued laminated timber. (6) Outer circumference of the part where a plurality of glulams abut in series
The length of the prestressed laminated timber according to claim 4 or 5, wherein the portion is wound by an auxiliary tool such as a square tubular body.
Method of manufacturing beams .

[0004] Each penetrating slot used in the above is provided.
For example, (1) a joined body of a pair of laminated timbers
Wherein the joined body has a length corresponding to the length of the surface of one of the opposing glulams.
Through holes derived from long grooves cut along the entire length in the direction
Or (2) connecting a pair of glued laminated lumber
And the joined body is formed on each side of both opposing glulams.
Penetration length from long groove cut along the entire length in the longitudinal direction
It may have a hole (sheath hole).

[0005]

Embodiments of the present invention will be described below with reference to the drawings. About glued lumber. Glued lumber is made from lumber and is ground to a predetermined size (lamina having a thickness of 2.
5 to 3.5 cm of replacement board) and small square wood, water content 8 to 1
It is a material manufactured by drying to 2%, polymerizing and bonding them with the fiber direction aligned in the longitudinal direction, and has less cracks and irregularities than the original material (wood). Various kinds of conifers (pine, larch, spruce, larch, spruce, hinoki, cedar, etc.) and hardwoods (beech, zelkova, elm, etc.)
Lauan et al.) Are used. There are two types of laminated timber: a construction laminated timber and a durable structural laminated timber. The general manufacturing process of a structural glued laminate is as follows. Raw wood-Lumber-Drying-Roughing-Sorting-Defect removal-Horizontal cutting-Vertical cutting-Finishing-Inspection-Lamina combination-Adhesive application-Compression (adhesion)-Curing-Square cutting-Finishing. As the adhesive in the manufacturing process of the structural laminated wood, a resorcinol resin adhesive is mainly used, but a phenol / resorcinol co-condensation resin adhesive, a tannin-modified phenol resin adhesive and the like are also used. At the time of bonding, an adhesive is applied to the surface to be bonded of the lamina, such as a ground plate, which constitutes the glued laminate, in an amount of 150 to 2 per adhesive layer.
Applying about 50 g / cm ^{2 and} tightening with a clamp or a press with a pressing force of 5 to 15 kgf / cm ² are performed. At this time, pressing and bonding are preferably performed while heating at 130 ° C. or less. Therefore, the characteristics of the glued laminated wood are (1) Lamina such as sawn board or square wood is the main raw material, (2) it is integrated by adhesive,
(3) When integrated, the fiber directions are aligned in parallel.
Then, (4) a material having an arbitrary large cross-sectional area is obtained, and (5)
It has a higher bending strength than the constituent material (wood) and can have a high allowable stress.

According to the present invention, the penetration is made over the entire length in the longitudinal direction.
A plurality of glued laminated lumber with long holes are abutted in series and extended,
Insert a tendon into the communication slot formed by that,
Elongated high strength by applying prestressed by post-tensioner
Laminated wood . Also, at this time, the plurality of glulams
An adhesive layer may be interposed between the contact surfaces that are in series contact.
preferable. As such, in which the length maximization and high strength due to the series junction of a plurality of laminated wood simultaneously be achieved.

The example shown in FIG. 1 is a side view (a) and a front view (b) of a prestressed laminated timber beam made of a bonded laminated timber.
The left and right two rectangular glued laminated timbers 1 and 1 are arranged in series in the longitudinal direction, and the tension member 3 is inserted into the elongated through hole 2 therein, and the prestress due to post tension is applied to the tension member 3. It has been granted. Note that the end of the tension member 3 is fixed to the fixing device 4 (consisting of the plate 41 and the nut 42).
The two glued laminated timbers 1,1
Each of the ends 1a, 1a contacting may be compressed and abutted in a mere contact state. However, an adhesive (not shown) is applied to the surfaces of the ends 1a, 1a and strongly compressed and bonded. It is also preferable to use Such a prestressed laminated timber beam 10 is long and has increased bending strength and compressive strength, and can greatly expand the field of use of the laminated timber, which has been conventionally limited in use. . In this manner, a plurality of laminated materials 1 are brought into contact in series,
When the prestress is applied by inserting the tension members 3 into the laminated material, a long high-strength laminated material can be manufactured with a plurality of short laminated materials 1. The prestressed laminated wood has a bending strength similar to that of a single long laminated wood, despite the fact that there is an abutting portion between the laminated woods 1.

Next, a description will be given of a means for forming the through-holes 3 in the bonding glue 1. First, FIG.
(E) is a cross-sectional view of various bonded laminated materials 1, 1... Manufactured by facing and bonding two element laminated materials 1 ', 1'. Generally, as shown in FIG. 3, a perspective view of the element glue 1 'is shown in FIG. 4 (a tightening frame 61, a bolt 62, and a nut 63).
), The surfaces of the long grooves 3a are made to face each other, compressed via an adhesive 5, and cured and joined. The above-mentioned laminated wood 1 'may be manufactured by dividing a factory-produced laminated wood in half, or may be a factory-produced laminated wood itself.

FIG. 2 (a) shows a laminated body 1 'having one laminated body 1' and another long groove (not shown).
Are abutted and bonded via an adhesive 5 with the long groove surface inside, and the through hole 3
Is formed. (B) shows two glued laminated members 1 ', 1' each having a long groove (not shown), and the adhesive 5
In FIG. 3 (c), two laminated bodies 1 ', 1' each having a triangular long groove (not shown) are placed with the surface of the long groove inward. And is joined by an adhesive 5 via an adhesive 5, and has a rectangular through hole 3 formed by combining the two and formed inside by combining triangles. As shown in (d), after a deep groove (not shown) is cut from one surface of the large laminated body 1 ', the filling piece 11 is inserted and bonded to the intermediate depth of the deep groove via the adhesive 5. The through-hole 3 is formed therein by the insertion of the filling piece 11. (E) shows a through-hole formed by sandwiching the filling pieces 11 and 11 'between one of the pre-assembled pieces 1' and the other pre-assembled piece 1 'to a depth at which the two filling pieces do not come into contact. 3 are formed, and the laminated body 1 'excluding the through-hole 3 portion and the filling pieces 11,
The contact surface 11 ′ is joined via an adhesive 5. The through-hole 3 can be formed as described above, but the through-hole 3 may be formed by means other than those shown in the above (a) to (e). In addition, the above-mentioned adhesion | attachment of the particle | grain laminated materials 1 ', or the filling piece 11 and the particle | grain laminated material 1'
For the bonding with the adhesive, a resorcinol resin adhesive, a phenol / resorcinol co-condensation resin adhesive, a tannin-modified phenol resin adhesive, or the like can be used as described in the production of the structural laminate. In the bonding at that time, an adhesive is applied to the surface of the laminated body 1 'in the same manner as described above, and the surface is tightened by a clamp or a press.
Pressing and bonding while applying heating of 30 ° C or less.

In manufacturing the long beam 10 made of prestressed laminated wood, as shown in FIG. 5, a perspective view of a connecting end portion of the laminated woods 1 and 1 has a laminated wood having a through-hole 3. It is more preferable that the outer surfaces of both ends of the first and the first are wound with an auxiliary tool 7 such as a rectangular tube. The auxiliary tool 7 may be used temporarily, but may be made of a high-strength material to serve as a reinforcing tool for the connection end to which prestress is applied.

Further, since the stress distribution around the fixing portion is complicated and a tensile stress is locally generated, it is preferable to reinforce the periphery. As shown in a perspective view of the periphery of the fixing portion in FIG. 6, the peripheral portion is wound around a sheet made of a new material that does not corrode, for example, to reinforce the reinforcing member 8. A tool such as the auxiliary tool 7 'in FIG. 5 may be used.

About grout. It is desirable to grout to prevent corrosion of the tendon. Regarding the grout of the tendon, after-bond (the curing of the grout is completed later) and unbonding (the grout is not cured) to respond to needs such as labor saving and high quality, a tendon has been developed. The above-mentioned steel material can be applied to the prestress introduced into the glued laminated wood. As the grout, a grout such as an epoxy resin can be used.

As the tendon, generally, a PC steel rod,
PC steel materials such as PC steel wires and PC steel strands are used,
A new material such as a high-strength synthetic resin, carbon fiber, or a composite material of each of the above materials can also be used. Further, as the fixing system of the fixing unit, a screw fixing system or a wedge fixing system via the supporting plate as described above can be adopted. further,
The cross-sectional shape of the through-hole may be square, circular, or any other shape.

[0014]

According to the present invention, it is possible to easily construct a wooden structure in a field where a structure receiving a high load could not be constructed with a wooden structure because of insufficient strength. Become. According to the present invention, a plurality of glulams are abutted in series and a prestress is applied by inserting a tension material into a through-hole. According to the present invention, a long high-strength glulam is manufactured with a plurality of short glulams. The produced long prestressed glued laminated lumber has the same bending strength and strength as one long glued laminated lumber without any continuous part, despite the abutment between the laminated glues. It develops compressive strength. Therefore, a long, high-strength glued laminated timber (press
(Trest glued laminated timber beams) . It is possible to construct a wooden structure such as a wooden bridge having a sufficient strength and suitable for expressing the natural environment, a structure in the natural environment having a sufficient strength, an important cultural property, and the like.

[Brief description of the drawings]

FIG. 1 Prestressed glulam manufactured with bonded glulam
The side view of a long beam .

FIG. 2 is an explanatory cross-sectional view showing means for forming various types of bonded laminated members having a long through hole therein.

FIG. 3 is a perspective view of a laminated body having long grooves.

FIG. 4 is an explanatory view of the production of a bonded laminated wood using a fastening tool.

FIG. 5 is a perspective view of a connection end portion of two glulams when a long beam made of a prestressed glulam is manufactured.

FIG. 6 is a perspective view of the vicinity of a fixing portion of a long beam made of prestressed laminated wood.

[Explanation of symbols]

1: Bonded laminated wood, 1 ': Elementary laminated wood 1a: End 2: Tensile material, 3: Through-hole, 3a: Long groove 4: Fixing tool 41: Plate, 42: Nut, 5: Adhesive 6: Tightening tool 61: clamping frame, 62: bolt, 63: nut, 7,7 ': aid 10: prestressed glulam made long beams long (Puresutore
Strut glued lumber beam ) 11, 11 ': Filling piece

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Tsutomu Kubota 2326, Shinjuku, Matsumoto-shi, Nagano Nagano Giken Co., Ltd. (72) Inventor Seiroku Miyama 943-74 Shimohideya, Okegawa-shi, Saitama (56) References JP-A-6-229065 (JP, A) JP-A-7-52110 (JP, A) JP-A-60-162612 (JP, U) JP-A-57-196713 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B27M 3/00 B27M 1/00 B27M 1/02

Claims (6)

(57) [Claims] 1. A plurality of laminated members having through-holes extending over the entire length in the longitudinal direction are extended in contact with each other in series, and the communication elongated holes formed thereby are tensioned in a state in which prestress by a tension member is applied. formed therethrough, prestressed laminated timber made length and characterized by being constituted of high strength laminated wood long
Beams . 2. An adhesive layer is interposed on a contact surface where a plurality of glued laminated members are in contact with each other in series.
2. A beam made of prestressed laminated timber according to 1 . 3. A portion where a plurality of glulams abut in series.
The prestressed laminated timber beam according to claim 1 or 2 , wherein an outer peripheral portion of the prestressed laminated timber is wound by an auxiliary tool such as a rectangular tube . 4. A plurality of laminated members having through-holes extending over the entire length in the longitudinal direction are abutted and extended in series, and a tension member is inserted into a communication elongated hole formed thereby. A method of manufacturing a long beam made of a prestressed laminated wood , wherein the long beam is made into a long high-strength laminated wood. 5. The method of manufacturing a prestressed laminated timber beam according to claim 4 , wherein an adhesive layer is interposed on a contact surface where a plurality of glued laminated materials are abutted in series. 6. A portion where a plurality of glulams abut in series.
The method for manufacturing a prestressed laminated timber beam according to claim 4 or 5, wherein an outer peripheral portion of the long beam is wound by an auxiliary tool such as a rectangular tube .