JP4061343B2 - How to repair and strengthen wood - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for repairing / strengthening various molding materials such as wood and concrete, and more particularly to a method for repairing / strengthening various materials obtained by filling and solidifying cracks and voids in various materials with an adhesive. is there.
[0002]
[Prior art]
Conventionally, a method of repairing cracks and cracks in concrete, wood, and other various materials by injecting and solidifying an adhesive at a repair target site is a common means. Such prior art examples include those described in the prior art section of Japanese Patent Laid-Open Nos. 63-20657 and 2002-121901, for example.
In these prior arts, the injection filling of the adhesive into the crack to be repaired is performed by various pressurization methods, that is, the surface of the crack is closed with a sealing material and the internal space is pressurized to inject the adhesive, or This was done by injecting adhesive into the individual cracks with a pressure injection device.
[0003]
[Problems to be solved by the invention]
However, the above prior art has the following disadvantages. That is, in the above example employing a sealed space with a sealing material, high-strength confidentiality is required in the sealed space including the tip portion such as a crack. The reason is that the adhesive cannot reach the tip of cracks and cracks unless sufficient pressure is applied. However, in reality, even if an adhesive is injected under high-strength confidentiality, air is often left in a state of being pressed and compressed by a pressure adhesive at the end portion such as a crack. In many cases, repair strength cannot be obtained. When the pressure is increased to increase the degree of filling of the adhesive, the seal is often broken and the adhesive is scattered.
On the other hand, in the example in which the adhesive is injected into the individual cracks by the pressure injection device, not only a large number of devices are required, but also the adhesive and air are not completely replaced at the crack tip, and air remains. As a result, the required repair strength may not be obtained.
Moreover, in the said prior art, since the adhesive filling condition cannot be confirmed, the flow direction of the adhesive cannot be controlled after the start of the injection of the adhesive, and proper filling is difficult.
[0004]
[Means for Solving the Problems]
The present invention is
A method of repairing / strengthening wood comprising filling a crack or other void in a target wood to be repaired / strengthened under a reduced pressure atmosphere, comprising the following steps: It is intended to solve the above-described conventional problems.
That is,
(E) A flexible transparent resin sheet that enables observation of the behavior of the injected adhesive in the part or the whole of the part to be repaired / strengthened of wood forms a seal space that can be depressurized and forms a seal surface that can be decompressed. A step of forming reinforcement / exhaust means during decompression between the transparent resin sheet,
(F) a step of setting a chamber having an exhaust port serving also as an adhesive inlet to the chamber as an adhesive storage means at a position higher than the seal space;
(G) connecting a decompression means such as a vacuum cleaner to the exhaust port of the chamber to suck and remove cracks in the wood to be repaired and dust present in the seal space;
(H) Next, a flexible transparent resin sheet is poured into the chamber with a hand or a spatula while injecting a sufficient amount of adhesive for repair and observing the inside of the seal space through the flexible transparent resin sheet as a seal member. Guiding the adhesive to the cracked part via
(E) A process of reconnecting a vacuum cleaner such as a vacuum cleaner to the exhaust port of the chamber and exhausting the air, reducing the pressure of the seal space and replacing the air inside the crack with an adhesive, and filling the adhesive throughout the crack. ,
(F) A step of removing the chamber, the transparent resin sheet, and the like when the fluidity of the adhesive is lost and it is no longer necessary to hold the adhesive by the sheet .
[0005]
Further, in the above-described wood restoration / strengthening method, the reinforcing / exhaust means in the step ( a ) may be constituted by a mesh-like sheet made of a reinforcing fiber material.
[0006]
In any of the above methods for repairing / strengthening wood, the chamber may be formed of a transparent resin material that is non-breathable and has shape retention.
[0007]
Furthermore, in any of the above-described methods for repairing / strengthening wood, the reinforcing fiber material may be composed of carbon fiber, Kepler fiber, or aramid fiber.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
One embodiment of the present invention is as follows.
a: It is possible to observe the behavior of the adhesive in which a part or the whole of the wood having cracks is further infused on the surface of the wood to be repaired on the mesh sheet as a spacer as a spacer. In addition, the sheet is wrapped with a flexible transparent resin sheet and, if necessary, the sheet end is locked to the wood surface to form a seal space. The mesh sheet as a spacer forms a gap between the transparent resin sheet and the wood surface to ensure an exhaust passage during decompression and covers projections on the wood surface to prevent damage to the transparent sealing material. Have the effect of
b: A chamber having an exhaust port and communicating with the seal space at the bottom is connected to the seal space. The exhaust port also serves as an adhesive injection port into the chamber as an adhesive storage means.
c: A pressure reducing means such as a vacuum cleaner is connected to the exhaust port of the chamber to suck and remove cracks in the wood to be repaired and dust present in the seal space.
d: Next, a sufficient amount of adhesive for repairing is injected into the chamber. Glue is
Epoxy resin-based materials are used because they have excellent properties such as adhesiveness, durability, water resistance, alkali resistance, and dimensional stability. It is not limited to an epoxy resin system.
e: While observing the inside of the seal space through the transparent resin sheet, which is a seal member, the adhesive is guided to the cracked portion with a hand or a spatula.
f: Decompressing means such as a vacuum cleaner is again connected to the exhaust port of the chamber and exhausted, the seal space is decompressed, the air inside the crack is replaced with the adhesive, and the adhesive is filled throughout the crack.
g: When the fluidity of the adhesive is lost and it is no longer necessary to hold the adhesive by the sheet, the chamber, the transparent resin sheet and the like are removed. In some cases, the mesh sheet may be left as it is.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described.
Object of repair: Bay pine laminated timber (E = 110 tf /?) Was used for the test body, and a steel plate insertion drift pin joint was applied to simulate the column-beam joint. The beam was 492 mm depending on the assumed beam span, and the column was 302 mm. (1) 1 / d ≥ 8 to 10 (2) End distance ≥ 7d (3) Edge distance ≥ 4d (4) The pin with the largest burden is the first under the condition of pin mutual distance ≥ 7d. The design was performed in such a way that the short-term allowable load was reached when the yield strength was reached. The shape of the test body shape T and the force device are as shown in FIG.
The number of pins is 24, and the diameter is column side ψ10 mm and beam side ψ16. The applied force was controlled by deformation, and was repeated 5 times at each deformation angle while gradually increasing the deformation level. The deformation angle was set as an index by calculating the deformation angle 1/51 rad. Corresponding to the load of 11.76 kN at which the outermost pin of the drift pin joint yields based on the results of previous experiments. As a result of the applied force, innumerable cracks are generated in the columns and beams, and the material portion around the drift pin is crushed to generate voids.
[0010]
The outline of the work procedure from the preparation to the repair of the specimen is as follows.
First, the test body T was attached to a force applying device, and a virgin force was applied. Thereafter, repair was performed by filling the adhesive with the test piece T being attached to the force device at a neutral position with a deformation angle of 0 rad. After a curing period of one week or more, the following findings were obtained as a result of verifying the repair after applying the repair after the repair with the same contents as the virgin force.
The strength and deformation performance of the steel sheet drift pin joint can be recovered by repairing the adhesive.
The effects of adhesive repair include (1) crack adhesion, (2) gap filling, and (3) adhesive bonding, and (3) may provide an adhesive strength higher than the original shape.
In the case of using an elongated drift pin to increase the plastic deformation capacity, the accumulation of plastic strain on the pin becomes excessive as the number of repeated application increases, and some of the pins fractured in this experiment. When such a repair is performed on an actual structure, it is necessary to consider the replacement of the drift pin prior to filling with the adhesive.
[0011]
Next, repair according to the embodiment will be described.
FIGS. 1 and 2 respectively show a flexible transparent resin sheet that forms a sealing space, a chamber made of a shape-retaining transparent resin material, a mesh-like sheet that is a net-like body as a spacer, and related structures of repair target wood in this embodiment. It is sectional drawing and a perspective view which show. In the figure, 1 is a flexible transparent resin sheet that is wound and affixed to the surface of a wood 3 to form a sealing space, and 2 is a mesh sheet interposed between the surface of the wood 3 and the flexible transparent resin sheet 1. Thus, as described above, the close contact between the transparent resin sheet 1 and the wood surface 3 is prevented, and a gap is formed between the two to secure an exhaust passage during decompression. The mesh-like sheet 2 is left as it is, unless it is particularly sticking to aesthetics. However, if a transparent material is used, the aesthetic appearance is less likely to be lost.
Further, if a reinforcing fiber material such as carbon fiber, Kevlar fiber or aramid fiber is used, it is left as it is after the repair and is effective as a further means for reinforcing wood.
[0012]
Reference numeral 4 denotes a chamber connected to the flexible transparent resin sheet 1 so as to communicate with the sealing space. The chamber 4 is formed of a transparent resin material that is non-breathable and retains its shape and is higher than the required filling portion of the adhesive in the wood. It is provided at a position, and has an exhaust port 5 also serving as an adhesive inlet at the top. Further, 3a is a crack generated in the wood 3, 3b is a gap generated when the drift pin 6 is deformed by the stress on the wood and crushes the wood, and 3c is a gap between the members.
[0013]
Now, as described above, the damaged portion of the wood that has been damaged by cracks, voids, etc. is filled with an adhesive and repaired. In this embodiment, the repair is performed as follows. The explanation will be focused on.
B: First, the mesh sheet 2 is wound around the repaired portion of the wood 3, and the flexible transparent resin sheet 1 is wound around the entire circumference of the wood 3, and the end portion is pressed and sealed with an adhesive tape or the like. Form.
B: The chamber 4 is connected to the flexible transparent resin sheet 1, and the bottom of the chamber 4 and the sealing space are connected. The chamber 4 is provided at a position where the adhesive is required to be filled in the wood 3, that is, at a position higher than the crack 3a and the gap 3b.
C: A predetermined amount of adhesive is injected into the chamber 4 from the adhesive injection port 5 which also serves as an exhaust port. In this embodiment, the adhesive uses a fluid epoxy type adhesive.
D: The adhesive once stored in the chamber 4 starts to flow and diffuse in the sealing space formed by the mesh sheet 2 between the surface of the wood 3 and the flexible transparent resin sheet 1. At this time, while observing the behavior of the adhesive through the flexible transparent resin sheet 1, the adhesive is guided to a required filling location such as the crack 3 a with a spatula or the like.
E: Along with the flow diffusion of the adhesive, an appropriate pressure reducing means (not shown) is connected to the exhaust port also serving as the adhesive injection port to start the pressure reduction in the sealing space. The air staying at the tip portion due to the adhesive reaching the crack 3a or the like is easily replaced with the adhesive by the pressure reducing operation and sucked into the chamber 4 as bubbles, and then into the atmosphere via the pressure reducing means. Dissipated. Since the bubbles pass through the adhesive in the chamber 4, the progress of replacement of air and adhesive is observed and grasped from the outside of the chamber 4. In addition, by performing decompression until the adhesive is solidified, the flexible transparent resin sheet 1 can be prevented from being damaged due to the adhesive flowing down to the lower side of the sealing space. Further, the pressure reduction of the sealing space is sufficient if the amount of exhaust exceeds the amount of air entering the space, and therefore the airtightness of the flexible transparent resin sheet 1 is not necessarily required to completely block the entry of the atmosphere. However, the replacement of air and adhesive becomes more complete as the degree of vacuum increases.
In this example, after filling the required part of the adhesive, the evacuation is continued for about 1 hour, and the evacuation is stopped in a state where the viscosity of the adhesive is considerably increased. The outer periphery of the sheet 1 was supported by a plate material. Thus, the adhesive solidified after 24 hours and was cured for another week to complete the repair.
[0014]
In order to confirm the state of filling of the adhesive, the repaired wood was split and observed, and it was confirmed that the adhesive had penetrated to the tip details at the repaired points such as cracks and voids.
[0015]
【The invention's effect】
As described above, the invention of the present application is made in a reduced pressure atmosphere in the cracked part and the gap part in various materials such as wood and concrete materials, so that the crack part and the gap part etc. Even at the tip details, air is appropriately replaced with adhesive, and it becomes extremely easy to repair and strengthen various materials damaged by the force of an earthquake or the like. Therefore, for example, it greatly contributes to the emergency repair and reinforcement of structures damaged by earthquakes.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a related configuration of a flexible transparent resin sheet forming a sealing space, a chamber made of a shape-retaining transparent resin material, a mesh sheet as a spacer as a spacer, and repair target wood.
FIG. 2 is a perspective view of the same.
FIG. 3 is a plan view showing a shape of a material to be repaired (test body) and a pressing device in an example.

Claims (4)

A method of repairing / strengthening wood comprising filling a crack or other void in a target wood to be repaired / strengthened under a reduced pressure atmosphere, the method comprising the following steps.
(A) A flexible transparent resin sheet that enables observation of the behavior of the injected adhesive in the part or the whole of the part to be repaired / strengthened of the wood, which forms a sealed space that can be depressurized and forms the seal surface and the flexibility of the wood A step of forming reinforcement / exhaust means during decompression between the transparent resin sheet,
(B) a step of setting a chamber having an exhaust port serving also as an adhesive injection port to the chamber as an adhesive storage means at a position higher than the seal space;
(C) connecting a decompression means such as a vacuum cleaner to the exhaust port of the chamber to suck and remove cracks in the wood to be repaired and dust present in the seal space;
(D) Next, a flexible transparent resin sheet is poured with a hand or a spatula while injecting a sufficient amount of adhesive into the chamber and observing the inside of the seal space through the flexible transparent resin sheet as a seal member. Guiding the adhesive to the cracked part via
(E) A process of reconnecting a vacuum cleaner such as a vacuum cleaner to the exhaust port of the chamber and exhausting the air, reducing the pressure of the seal space and replacing the air inside the crack with an adhesive, and filling the adhesive throughout the crack. ,
(F) A step of removing the chamber, the transparent resin sheet, and the like when the fluidity of the adhesive is lost and it is no longer necessary to hold the adhesive by the sheet . 2. The method for repairing / strengthening wood according to claim 1 , wherein the reinforcing / exhausting means in the step ( a ) comprises a mesh sheet made of a reinforcing fiber material. Claim 1 3. The method for repairing / strengthening wood according to claim 2, wherein the chamber is formed of a transparent resin material that is non-breathable and has shape retention.   4. The method for repairing / strengthening wood according to claim 2, wherein the reinforcing fiber material is any one of carbon fiber, Kepler fiber, and aramid fiber.

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