Adhesive-type load-bearing structural surface, construction method for adhesive-type load-bearing structural surface, and adhesive specification determination support program

Abstract

To provide an adhesion type bearing force structure plane having a high floor magnification even fixed only with an adhesive agent without striking a nail material for construction by meeting a prescribed requirement, a construction method therefor and a program for supporting a decision of the prescribed requirement (of an adhesion specification) in order to solve problems of the conventional art.SOLUTION: The adhesion type bearing force structure plane of present invention is the bearing force plane in which a horizontal plane material or the like is fixed to a member for construction or the like by an adhesive agent and ''a shearing distortion of drop area 80% '' shows a value equal to or greater than a threshold and ''a shearing elasticity modulus'' shows a value within an allowable range. Here, ''the shearing distortion of drop area 80% ' is a value obtained by dividing the drop area 80% variation amount by an adhesion thickness and ''the shearing elasticity modulus'' is a value obtained by dividing an initial shearing force by an initial shearing distortion.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to horizontal structural surfaces (including floor and roof structural surfaces) used in wooden houses and the like, and more specifically to adhesive-type load-bearing structural surfaces in which horizontal surface materials are fixed to structural members or frame members using adhesive, a method for constructing such structural surfaces, and a program for assisting in the determination of the adhesive specifications. [Background technology]

[0002] According to the Building Standards Act, wooden buildings with three or more floors or a specified area (500m2) 2 ) or wooden houses that exceed a certain height (height 13m, eaves height 9m), a building confirmation is required, and therefore structural calculations are carried out when designing such wooden buildings. On the other hand, for wooden buildings two stories or less that are used for residential purposes and fall below a certain floor area (hereafter referred to as "general wooden buildings"), structural calculations do not need to be carried out as a general rule if simplified calculations of wall volume etc. and specification regulations are met, and this is often omitted. The Building Standards Act Enforcement Order contains provisions regarding construction specifications (framework necessary for structural strength), and it is common for each specification to be determined in accordance with these provisions when designing general wooden buildings.

[0003] The construction specifications stipulated in the Building Standards Act Enforcement Order present various types of bearing wall structures (frameworks with walls) and also indicate the strength index (so-called wall factor) according to the structural type (framework type). In other words, the wall factor indicated here is used as a reference to select the type of bearing wall required for each part of each floor when designing the entire building.

[0004] As mentioned above, the Building Standards Act Enforcement Order prescribes load-bearing walls, but does not specify "horizontal structural surfaces" such as the floor structure (hereafter referred to as "floor horizontal structural surface") or the roof structure (hereafter referred to as "roof horizontal structural surface"). Of course, for general wooden buildings, there is no need to carry out special structural calculations for the horizontal structural surfaces. In other words, in terms of the load-bearing structure of wooden buildings, load-bearing walls are given more importance than horizontal structural surfaces.

[0005] However, the horizontal structural planes also function as load-bearing structures, and when considering the strength of a wooden building as a whole, it is natural that the strength of the horizontal structural planes cannot be overlooked. The main role of the horizontal structural planes is to transmit horizontal forces, including earthquake loads, to the load-bearing walls. If the rigidity of the horizontal structural planes is low, they may deform or bend significantly, or may be damaged or destroyed before the load-bearing walls do, and in such cases the load-bearing walls cannot perform to their full potential. If the horizontal structural planes transmit horizontal forces appropriately (in other words, in a balanced manner) to the surrounding load-bearing walls, the load-bearing walls will function effectively, and as a result, the wooden building will be able to resist external forces. In other words, the rigidity, strength, and toughness (hereinafter collectively referred to as "strength") of the horizontal structural planes contribute in no small way to the strength of the wooden building as a whole, and for this reason the horizontal structural planes are also required to have a considerable strength.

[0006] Since horizontal structural surfaces affect the strength of wooden buildings, there are times when the strength of horizontal structural surfaces is actively evaluated even for general wooden buildings. For example, housing manufacturers may emphasize that their wooden buildings are stronger than those of other companies by highlighting that the horizontal structural surfaces are also highly resistant in addition to the bearing walls. In such cases, the standard indicator of the strength of the horizontal structural surfaces of floors is the "floor factor (here, the horizontal structural surfaces of the roof are also referred to as the "floor factor"). The Act on Promotion of Quality Assurance of Housing (hereinafter referred to as the "Housing Quality Assurance Act") stipulates earthquake resistance grades (grades 1 to 3) as housing performance indicators, and the floor factor is one of the factors used to determine this earthquake resistance grade. The floor factor is determined in accordance with the Japanese Housing Performance Indication Standards stipulated in the Housing Quality Assurance Act.

[0007] Furthermore, the strength of the horizontal structural components (i.e., the floor magnification) is also important for long-lasting quality housing, which is eligible for special tax treatment. Specifically, to be certified as a long-lasting quality house, a certain earthquake resistance grade (grade 2 or higher) is required, which means that an appropriate floor magnification is necessary. In addition, when wooden buildings other than detached houses are constructed of wood, such as schools, kindergartens, offices, and public facilities, structural calculations of the horizontal structural components are required depending on the scale and use, and as a result, horizontal structural components with an appropriate floor magnification are sometimes planned. In particular, the greater the distance between the load-bearing walls (i.e., the larger the space is desired), the higher the magnification of the horizontal structural components is required.

[0008] As mentioned above, the floor multiplier is determined according to the Japan Housing Performance Indication Standards. Specifically, several structural types of horizontal structural surfaces are exemplified, and a floor multiplier (existing floor multiplier) is set for each structural type. In addition, although the "Allowable Stress Design of Wooden Frame Construction Houses (2017 Edition)" does not use the term "floor multiplier," it does indicate the relationship between the specifications of the horizontal structural surface and its strength (allowable shear strength per unit length). The allowable shear strength per unit length shown here can be converted to the floor multiplier by dividing it by the conversion value of 1.96 (kN / m).

[0009] The structural types (specifications) of horizontal structural components listed in the Japan Housing Performance Indication Standards and the Allowable Stress Design for Wooden Frame Construction Houses (hereinafter collectively referred to as "Conventional Standards, etc.") are all determined by a combination of the type of surface material, the nail specifications (type and installation interval), the joist specifications (dimensions and installation interval), and the joint specifications between the joists and the beams. Note that "nails" here refers to a general term for fasteners such as commonly used round iron nails (N nails, CN nails), screw nails, and screws. Therefore, when designing horizontal structural components, it was common to select from structural types based on these combinations, and it was extremely rare to plan structural types that included other elements (for example, the use of fixing materials other than nails).

[0010] In addition, according to conventional standards, the floor ratio also varies depending on the arrangement of the nails, and a format in which nails are installed in three or more rows only on one side of the floor material (so-called "river-shaped" format) has a smaller floor ratio than a format in which nails are installed around the entire circumference of the floor material (so-called "square-shaped" format). For example, in the Japanese Housing Performance Indication Standards, when round iron nails N75 are nailed into structural plywood with a thickness of 24 mm or more at intervals of 150 mm or less, the floor ratio (existing floor ratio) is set to 3.0 for the square-shaped format, while the floor ratio is set to 1.2 for the square-shaped format. Thus, the current situation is that the horizontal structural surface of the square-shaped format cannot achieve a very high floor ratio. On the other hand, the square-shaped format is advantageous in terms of cost because it is easy to design the arrangement of beams and the volume of beams can be reduced, so a horizontal structural surface with a high floor ratio using the square-shaped format is in demand.

[0011] Incidentally, when determining the strength of a floor, such as the floor magnification and allowable shear strength, an envelope curve is generally used. This envelope curve is a widely known graph, as shown in "Allowable Stress Design for Wooden Frame Construction Houses," and is a curve that shows the relationship between the load and the deformation angle obtained from the in-plane shear test of the horizontal structural member. Specifically, as shown in the detailed diagram of the test specimen in Figure 13, a force is applied to one side of the upper end of the horizontal structural member in a vertical position in stages until the deformation angle is set in advance (however, the force is applied repeatedly in a positive and negative alternating manner), and the curve that connects the results obtained at each loading stage is the envelope curve.

[0012] Figure 14 shows the envelope of a horizontal structural member in which floor materials are fixed to beams by nails. The horizontal axis shows the deformation angle (rad) and the vertical axis shows the load. As shown by this envelope, the horizontal structural member fixed by nails has a certain deformation angle (approximately 60×10 -3The load increases until a certain displacement angle (rad) occurs. In other words, it can be said that the nail resists the load until this certain displacement angle occurs. It is generally assumed that wooden buildings will experience a displacement angle of about 1 / 120 rad in the event of a medium-sized earthquake, and a displacement angle of about 1 / 30 rad in the event of a large-scale earthquake. Therefore, it can be seen that the nail resists the horizontal structural surface showing the envelope in this figure until a relatively large displacement angle that exceeds that of a large-scale earthquake occurs.

[0013] However, looking at the envelope in this figure, we can see that the initial deformation angle graph rises gradually, meaning that even a relatively small load causes the deformation angle (1 / 120rad) assumed for a medium-scale earthquake. In other words, while the nail material effectively resists a relatively large range of loads, it has a weakness in that it easily deforms in a relatively small range of loads. The higher the rigidity of the horizontal structural members, the smoother the transfer of force to the walls, and the floor multiplier also tends to be evaluated as high, so solving this weakness can be seen as a major challenge.

[0014] Therefore, Patent Document 1 discloses an invention in which flooring materials are fixed to beams with adhesive in addition to nails so that they do not easily deform in a relatively small load range. The envelope curve of a horizontal structural surface fixed with adhesive has a large rise in the graph in the elastic range (initial deformation angle), and is characterized by not easily deforming in a relatively small load range. On the other hand, the envelope curve of a horizontal structural surface fixed with nails has a tough characteristic that the load does not decrease even when the deformation angle becomes large. In other words, by combining adhesive and nails, a hybrid horizontal structural surface is created that makes use of the characteristics of both, with the adhesive providing resistance in a small load range and the nails providing resistance in a large load range. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] JP 2019-027234 A Summary of the Invention [Problem to be solved by the invention]

[0016] The invention disclosed in Patent Document 1 is a horizontal structural member that utilizes the characteristics of adhesive and nails, and therefore has a structure that can resist a comprehensive range of loads (small and large load ranges), and can obtain a larger floor ratio than a horizontal structural member of the same standard that is fixed only with nails (standard horizontal structural member). However, because structural nails are hammered in to resist loads, wooden materials such as horizontal plane materials, structural members, and frame members are prone to cracking due to the structural nails. In other words, when the horizontal plane materials and structural members try to flexibly deform in response to the deformation performance of the adhesive, the structural nails restrain the deformation, causing cracks in the horizontal plane materials and structural members. In addition, in addition to applying the adhesive, it is necessary to hammer in the structural nails, which is somewhat time-consuming.

[0017] Therefore, the inventors of the present application came up with the idea of ​​gluing and fixing horizontal plane members to structural members using only adhesive, or adhesive and temporary fixing screws or nails (temporary fixing materials until the adhesive hardens). However, it goes without saying that fixing by adhesive alone (or adhesive combined with temporary fixing screws, etc.) does not allow for a horizontal structural member with a high floor multiplier.

[0018] The object of the present invention is to solve the problems associated with the prior art, that is, to provide an adhesive-type load-bearing structural panel that, by satisfying certain requirements, can exhibit a high floor multiplier even when fixed with adhesive alone (or with adhesive in combination with temporary fixing screws, etc.) without the need for hammering in structural nails, and can effectively resist earthquakes, etc.; a method for constructing the panel; and a program for assisting in the determination of the specified requirements (adhesive specifications). [Means for solving the problem]

[0019] The present invention was made based on an unprecedented idea that focuses on the fact that horizontal surface materials are fixed to structural members, etc. using only adhesive (or using adhesive in combination with temporary fixing screws, etc.) so that the "shear strain at 80% of the downward slope" and "shear modulus" described below meet specified requirements.

[0020] The adhesive load-bearing structural surface of the present invention is a load-bearing structural surface in which a horizontal surface member (or an inclined surface member) is fixed to a structural member (or a frame member) by an adhesive, and the "shear strain at 80% of the descending region" is a value equal to or greater than a predetermined threshold value, and the "shear modulus" is a value within a predetermined allowable range. Here, the "shear strain at 80% of the descending region" is a value obtained by dividing the 80% displacement amount at the descending region by the adhesive thickness, and this 80% displacement amount at the descending region is a displacement amount at the descending region of the displacement characteristic curve among the displacement amounts corresponding to 80% strength of the maximum load on the displacement characteristic curve. On the other hand, the "shear modulus" is a value obtained by dividing the initial shear force by the initial shear strain, and this initial shear strain is a value obtained by dividing the strain when the initial shear force is applied from 0 displacement by the adhesive thickness.

[0021] The adhesive-type load-bearing structural panel of the present invention may also have a shear strain of 500% or more at 80% downward deformation.

[0022] The adhesive load-bearing structural panel of the present invention may have a shear modulus of elasticity of 70 MPa or more and 500 MPa or less.

[0023] The adhesive-type load-bearing structural panel of the present invention can be a structure in which structural members are arranged around a horizontal surface member or the like (or around the horizontal surface member or the like and in a central band), and the horizontal surface member or the like is fixed with an adhesive. In this case, temporary fixing screws (or nails) are driven around the horizontal surface member or the like. These temporary fixing screws or the like can be driven at intervals of 300 mm or more.

[0024] The method for constructing an adhesive-type load-bearing structural surface of the present invention is a method for constructing the adhesive-type load-bearing structural surface of the present invention described above, and includes a design process and a surface material fixing process. In the design process, the adhesive specifications (including at least the type of adhesive and adhesive thickness) are determined, while in the surface material fixing process, horizontal surface materials, etc. are adhesively fixed to structural members, etc. in accordance with the adhesive specifications determined in the design process.

[0025] The method for constructing an adhesive-type load-bearing structural panel of the present invention can also be a method further comprising a temporary fixing step. In this case, in the surface material fixing step, structural members are placed around the horizontal surface members (or around the horizontal surface members and in the center band), and the structural members and the horizontal surface members are fixed with adhesive. In the temporary fixing step, temporary fixing screws are driven around the horizontal surface members (or around the horizontal surface members and in the center band) to temporarily fix the structural members and the horizontal surface members until the adhesive hardens.

[0026] The adhesive specification determination support program of the present invention is a program that supports specification determination of the adhesive-type load-bearing structural surface of the present invention, and has a function of making a computer execute a displacement characteristic curve generation process, a shear strain calculation process at 80% downward range, a shear modulus calculation process, and a judgment process. The specification of the adhesive-type load-bearing structural surface means a specification including at least the type of adhesive and the adhesive thickness. In the displacement characteristic curve generation process, a displacement characteristic curve showing the relationship between the displacement amount and the load of the adhesive-type load-bearing structural surface is generated, in the shear strain calculation process at 80% downward range, the shear strain at 80% downward range is calculated, and in the shear modulus calculation process, the shear modulus is calculated. In the judgment process, an adhesive specification in which the shear strain at 80% downward range is equal to or greater than a predetermined threshold value and the shear modulus is within a predetermined allowable range is judged to be an appropriate specification. Effect of the Invention

[0027] The adhesive-type load-bearing structural wall, the method for constructing the adhesive-type load-bearing structural wall, and the adhesive specification determination support program of the present invention have the following effects. (1) It is possible to obtain a structure that exhibits a significantly higher floor ratio than the strength-bearing structural members of the conventional technology. (2) It can be completed by simply applying adhesive, or by simply installing temporary fastening screws or the like and then applying adhesive, meaning that it can be constructed extremely easily. (3) Various adhesives can be used by appropriately designing the adhesive thickness. [Brief description of the drawings]

[0028] [Figure 1] FIG. 13 is an exploded perspective view showing a schematic diagram of a part of a horizontal structural plane in the case of a floor. [Diagram 2] (a) is an exploded perspective view showing a schematic of a portion of a horizontal roof structure in which a roof surface material is fixed onto a purlin and rafters, and (b) is an exploded perspective view showing a schematic of a portion of a horizontal roof structure in which a roof surface material is fixed onto a climbing beam. [Diagram 3] (a) is a plan view showing the back side of a horizontal surface material on which a fixed area is set, and (b) is a cross-sectional view showing a horizontal structural surface fixed in a river-shape. [Figure 4] A plan view showing the back side of a horizontal surface member having intermediate fixing regions set in two places in the middle portion. [Diagram 5] FIG. 11 is a graph showing an example of an envelope. [Figure 6] FIG. 4 is a graph showing an example of a displacement characteristic curve. [Figure 7] A model diagram explaining the shear modulus. [Figure 8] A result table summarizing the test cases and test results. [Figure 9] (a) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 1, (b) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 2, and (c) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 3. [Figure 10] (d) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 4, (e) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 5, and (f) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 6. [Figure 11](g) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 7, (h) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 8, and (i) is an envelope diagram obtained from the results of an in-plane shear test on the load-bearing structural surface of CASE 9. [Figure 12] FIG. 2 is a flow chart showing the flow of the main steps of the method for constructing an adhesive-type load-bearing structural panel of the present invention. [Figure 13] (a) is an explanatory diagram mainly showing the specifications of the beam materials among the specimens used in the in-plane shear test, and (b) is an explanatory diagram mainly showing the specifications of the horizontal plane materials among the specimens used in the in-plane shear test. [Figure 14] A graph showing the envelope of a horizontal structural member in which a horizontal plane member is fixed to a beam member by nail members. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] An example of an adhesive-type load-bearing structural wall, a method for constructing an adhesive-type load-bearing structural wall, and an adhesive specification determination support program according to the present invention will be described with reference to the drawings.

[0030] 1.Definition Before describing the embodiments of the present invention, the following definitions of terms used herein will be given.

[0031] (Horizontal surface material) Here, the board materials that form the floor base are referred to as "floor surface materials," the board materials that form the horizontal structural surface of the roof are referred to as "roof surface materials," and floor and roof surface materials are collectively referred to as "horizontal surface materials." Horizontal surface materials are manufactured using a variety of materials, including solid wood, plywood (including structural plywood), CLT (Cross Laminated Timber), Laminated Veneer Lumber (LVL), and molded fiberboard (MDF). Structural plywood is particularly suitable as a horizontal surface material, as it has little difference in strength in the direction of arrangement. In addition, if the horizontal surface material is made to a thick specification (24 mm or more for structural plywood), it is possible to suppress shear deformation of the surface material during shear deformation.

[0032] (Support material) For the sake of convenience, we will refer to wire materials (materials whose axial dimensions are extremely large compared to their cross-sectional dimensions) that support horizontal surface materials as "support materials." In other words, support materials are a general term for structural members and frame members, as well as girths and floor beams installed around the perimeter of the floor, floor joists placed in the middle of the floor, purlins and climbing beams used on the roof, and joists and supporting beams that are placed perpendicular to these floor joists. Types of wood materials such as general lumber, laminated lumber, and LVL can be used as support materials.

[0033] (load-bearing structure) As shown in Fig. 1 and Fig. 2, a frame structure in which a floor surface material 100 is fixed on a support material 200 is referred to as a "load-bearing structural surface" here. As described above, the horizontal surface material 100 is a general term for the floor surface material 100F and the roof surface material 100R. Therefore, the structure in which the floor surface material 100F is fixed on the support material 200 as shown in Fig. 1 is specifically referred to as a "floor load-bearing structural surface," and the structure in which the roof surface material 100R is fixed on the support material 200 as shown in Fig. 2 is specifically referred to as a "roof load-bearing structural surface." In other words, the load-bearing structural surface can be a general term for the floor load-bearing structural surface and the roof load-bearing structural surface. For example, the floor load-bearing structural surface can be a structure in which the floor surface material 100F is fixed on the girths 210, floor joists 220, and joists 230, which are the support material 200, as shown in Fig. 1. One of the roof load-bearing structural members can be constructed, for example, as shown in Figure 2(a) in which roof surface material 100R is fixed onto purlin material 240 and rafters 250, which are supporting materials 200, or as shown in Figure 2(b) in which roof surface material 100R is fixed onto climbing beam material 260, which is supporting material 200.

[0034] (Adhesive specifications for load-bearing structural surfaces) The adhesion specifications of the load-bearing structural surface are literally the specifications for adhesively fixing the horizontal surface material 100 and the supporting material 200, and include at least the type of adhesive and the adhesive thickness, and may also include the application area and the driving pitch of the "temporary fixing screws, etc." described later. Note that the specifications of the horizontal surface material 100 and the supporting material 200 for the adhesion specifications of the load-bearing structural surface are the result of selection of various elements including their materials, dimensions, and shapes.

[0035] (Structural screws, temporary fixing screws, etc.) For convenience, the general term for fasteners such as screws, round iron nails (N nails, CN nails), screw nails, and screws that are driven into the horizontal surface material 100, etc., will be referred to as "screws, etc." Furthermore, screws that structurally (permanently, so to speak) connect the horizontal surface material 100 and the supporting material 200 will be specifically referred to as "structural screws, etc." In contrast, screws that are used temporarily (temporarily, so to speak) until the adhesive hardens will be specifically referred to as "temporary screws, etc." In other words, structural screws, etc. are structural members that are expected to function to connect the horizontal surface material 100 and the supporting material 200 at least for the period during which the load-bearing structural surface is in use, while temporary screws, etc. are members that are not expected to have any particular structural function once the adhesive hardens.

[0036] (River-shaped format) The "river-shaped form" is one of the forms for fixing the horizontal plane member 100 to the support member 200. FIG. 3 is a diagram for explaining this river-shaped form, where (a) is a plan view showing the back side (lower surface side) of the horizontal plane member 100, and (b) is a cross-sectional view showing the load-bearing structural surface fixed in the river-shaped form. When fixing in the river-shaped form, an end fixing region 110 and an intermediate fixing region 120 are set on the horizontal plane member 100 as shown in FIG. 3(a). As can be seen from FIG. 3(b), the end fixing region 110 and the intermediate fixing region 120 are strip-shaped regions set in the range of the horizontal plane member 100 that is in contact with the support member 200, and therefore the end fixing region 110 and the intermediate fixing region 120 set on one horizontal plane member 100 are set to be approximately parallel (including parallel). In addition, in Figure 3, only one intermediate fixing area 120 is set for one horizontal plane member 100, but when two or more support members 200 are placed in between, two or more intermediate fixing areas 120 are set as shown in Figure 4 (two in this figure).

[0037] (Envelope) As mentioned above, the envelope curve is a widely known graph shown in "Allowable Stress Design for Wooden Frame Construction Houses," and is a curve that shows the relationship between the load and deformation angle obtained from an in-plane shear test on a bearing surface. Specifically, a load is applied to one side of the upper end of a bearing surface in a vertical position until a preset deformation angle is reached (however, the load is applied repeatedly in alternating positive and negative directions), and the curve that connects the results obtained at each loading step is the envelope curve.

[0038] FIG. 5 is a graph showing an example of an envelope curve. In general, an envelope curve is drawn with the deformation angle on the horizontal axis and the load on the vertical axis. max is the maximum load, P y is the yield strength, P u is the ultimate strength, δ u is called the ultimate deflection angle. Of these, the ultimate deflection angle δ u is the maximum load P max After the load reaches 0.8P max or 1 / 15 rad, whichever is smaller.

[0039] (Displacement characteristic curve) The displacement characteristic curve is a graph showing the relationship between the load and the amount of displacement obtained as a result of an in-plane shear test performed on a load-bearing structural member. This displacement characteristic curve is a convex curve as shown in Figure 6, and therefore the maximum load P max On the small displacement side (left side in the figure), the load increases (hereafter referred to as the "upward region"), and on the large displacement side (right side in the figure), the load decreases (hereafter referred to as the "downward region"). The maximum load P max 80% load (0.8P max For convenience, the 80% load that appears in the descending region will be referred to as the "80% load in the descending region" and the displacement that results in the 80% load in the descending region will be referred to as the "80% displacement in the descending region."

[0040] (shear modulus) FIG. 7 is a model diagram for explaining the shear modulus G. As shown in this figure, the shear modulus G is obtained by applying an initial shear force τ to a test specimen in which two adherends are fixed with an adhesive. The method for obtaining the shear modulus G will be specifically described below. A test specimen is prepared in which upper and lower adherends are arranged approximately horizontally and fixed with an adhesive, and a value of an initial displacement δ (for example, an initial displacement δ = 0.3 mm, etc.) is set in advance. Then, with the lower adherend fixed, an initial shear force τ is applied to the upper adherend in an approximately horizontal direction until the upper adherend changes from 0 displacement to the initial displacement δ. The value obtained by dividing the initial shear force τ obtained as a result by the initial shear strain γ is the shear modulus G. The initial shear strain γ is the value obtained by dividing the initial displacement δ by the adhesive thickness h.

[0041] (floor magnification) The floor factor is the short-term allowable shear strength calculated based on the envelope curve divided by the conversion value 1.96 (kN / m) mentioned above. a As shown in "Allowable Stress Design for Wooden Frame Construction Houses", is calculated based on the short-term standard shear strength P0, which is further determined by the smallest value among the values ​​obtained below. (a) Yield strength P y (b) Ultimate strength P u ×0.2 / D s (D s is the structural characteristic coefficient) (c) Maximum load P max ×2 / 3 (d) Strength at specific deformation

[0042] 2. Adhesive load-bearing structure Next, the adhesive-type load-bearing structural panel of the present invention will be described.

[0043] The adhesive-type load-bearing structural surface of the present invention is an adhesive-type load-bearing structural surface in which a horizontal plane member 100 and a supporting member 200 are adhesively fixed. The adhesive-type load-bearing structural surface of the present invention can be in a "river-shaped" form in which an end fixing region 110 and an intermediate fixing region 120 are set and then adhesively fixed, as shown in Figures 3 and 4, or in a so-called "square-shaped" form in which the entire periphery of the horizontal plane member 100 is fixed with adhesive. In addition, the horizontal plane member 100 and the supporting member 200 can be fixed only with adhesive, or can be fixed using a combination of adhesive and temporary fixing screws, etc.

[0044] The adhesive load-bearing structural member of the present invention must satisfy two requirements. The first requirement is that "the shear strain at 80% of the descending range is equal to or greater than a predetermined threshold (hereinafter referred to as the "strain threshold"). The inventors of the present invention have confirmed, through various tests, that if the strain threshold is set to a value of 500% or more, an adhesive load-bearing structural member with a high floor ratio can be obtained. The second requirement is that "the shear modulus is within a predetermined allowable range (hereinafter referred to as the "allowable range of shear modulus"). The inventors of the present invention have confirmed, through various tests, that if the allowable range of shear modulus is set to a value of 70Mpa or more and 500Mpa500% or less, an adhesive load-bearing structural member with a high floor ratio can be obtained.

[0045] (Test Example) The results of the actual tests are explained below. As shown in Figure 8, seven load-bearing structural surfaces (CASE 1 to CASE 7) with different adhesive specifications were prepared, and an in-plane shear test was conducted on each of them. For reference, tests were also conducted on CASE 8 (structural screws spaced 100 mm apart) and CASE 9 (structural screws spaced 75 mm apart), in which the horizontal surface material 100 and the supporting material 200 were fixed only with structural screws, without the use of adhesive. The adhesives a to d (Figure 8) used in this test each have the following characteristics. In this test, the "strain threshold" was set to 500%, and the "allowable range of shear modulus" was set to 70 MPa or more and 500 MPa or less. (Adhesive a) Highly extensible and has medium adhesive strength (Adhesive B) Has the same degree of extensibility as Adhesive A, but has inferior adhesive strength to Adhesive A. (Adhesive C) Has higher strength and greater extensibility than adhesive A (Adhesive d) High strength but brittle, and of adhesives a to d, it has the least extensibility.

[0046] CASE1 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with adhesive a with a thickness of 0.3 mm, and temporary fixing screws or the like are driven in at 100 mm intervals. Figure 9(a) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE1. As shown in Figure 8, the strength-bearing structural surface of CASE1 shows a shear strain of 1065% at 80% of the descending range, which exceeds the strain threshold of 500%, and therefore satisfies the first requirement. In addition, the shear modulus shows 175.9 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore also satisfies the second requirement. In other words, the strength-bearing structural surface of CASE1 was recognized as an adhesive-type strength-bearing structural surface of the present invention. And, its floor magnification is 4.76, which is recognized to be a higher floor magnification than the conventional technologies such as CASE8 (floor magnification 3.19) and CASE9 (floor magnification 3.92).

[0047] CASE2 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with adhesive a with a thickness of 0.9 mm, and temporary fixing screws or the like are driven in at 100 mm intervals. Figure 9(b) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE2. As shown in Figure 8, the strength-bearing structural surface of CASE2 shows a shear strain of 733% at 80% of the descending range, which exceeds the strain threshold of 500%, and therefore satisfies the first requirement. In addition, the shear modulus is 298.1 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore also satisfies the second requirement. In other words, the strength-bearing structural surface of CASE2 was recognized as an adhesive-type strength-bearing structural surface of the present invention. And, its floor ratio is 5.55, which is recognized to be a higher floor ratio than the conventional technologies such as CASE8 (floor ratio 3.19) and CASE9 (floor ratio 3.92).

[0048] CASE3 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with adhesive a with a thickness of 0.9 mm, and temporary fixing screws or the like are driven in at 300 mm intervals. Figure 9(c) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE3. As shown in Figure 8, the strength-bearing structural surface of CASE3 shows a shear strain of 733% at 80% of the descending range, which exceeds the strain threshold of 500%, and therefore satisfies the first requirement. In addition, the shear modulus is 298.1 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore also satisfies the second requirement. In other words, the strength-bearing structural surface of CASE3 was recognized as an adhesive-type strength-bearing structural surface of the present invention. And, its floor ratio is 6.38, which is recognized to be a higher floor ratio than the conventional technologies such as CASE8 (floor ratio 3.19) and CASE9 (floor ratio 3.92). Comparing CASE 2 and CASE 3, the spacing between the temporary fixing screws is wider (100mm for CASE 2 and 300mm for CASE 3), and CASE 3 shows a higher floor multiplier. This shows that temporary fixing screws, unlike structural screws, do not contribute to the floor multiplier.

[0049] CASE4 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with adhesive b with a thickness of 0.3 mm, and temporary fixing screws or the like are driven in at 100 mm intervals. Figure 10(d) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE4. As shown in Figure 8, the strength-bearing structural surface of CASE4 shows a shear strain of 1132% at 80% of the descending range, which exceeds the strain threshold of 500%, and therefore satisfies the first requirement. In addition, the shear modulus is 86.6 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore also satisfies the second requirement. In other words, the strength-bearing structural surface of CASE4 was recognized as an adhesive-type strength-bearing structural surface of the present invention. And, its floor magnification is 4.85, which is recognized to be a higher floor magnification than the conventional technologies such as CASE8 (floor magnification 3.19) and CASE9 (floor magnification 3.92).

[0050] CASE5 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with adhesive b with a thickness of 0.9 mm, and temporary fixing screws or the like are driven in at 100 mm intervals. Figure 10(e) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE5. As shown in Figure 8, the strength-bearing structural surface of CASE5 shows a shear strain of 599% at 80% of the descending range, which exceeds the strain threshold of 500%, and therefore satisfies the first requirement. In addition, the shear modulus is 320.7 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore also satisfies the second requirement. In other words, the strength-bearing structural surface of CASE5 was recognized as an adhesive-type strength-bearing structural surface of the present invention. And, its floor ratio is 4.60, which is recognized to be a higher floor ratio than the conventional technologies such as CASE8 (floor ratio 3.19) and CASE9 (floor ratio 3.92).

[0051] CASE6 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with adhesive c with a thickness of 0.3 mm, and temporary fixing screws or the like are driven in at 100 mm intervals. Figure 10(f) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE6. As shown in Figure 8, the strength-bearing structural surface of CASE6 shows a shear strain of 998% at 80% of the descending range, which exceeds the strain threshold of 500%, and therefore satisfies the first requirement. In addition, the shear modulus shows 250.0 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore also satisfies the second requirement. In other words, the strength-bearing structural surface of CASE6 was recognized as an adhesive-type strength-bearing structural surface of the present invention. And, its floor magnification is 5.74, which is recognized to be a higher floor magnification than the conventional technologies such as CASE8 (floor magnification 3.19) and CASE9 (floor magnification 3.92).

[0052] CASE7 is a test specimen in which the horizontal plane member 100 and the supporting member 200 are fixed with an adhesive d having a thickness of 0.3 mm, and temporary fixing screws or the like are driven in at 250 mm intervals. FIG. 11(g) shows the envelope curve obtained as a result of an in-plane shear test performed on the strength-bearing structural surface of CASE7. As shown in FIG. 8, the strength-bearing structural surface of CASE7 shows a shear strain of 252% at 80% of the descending range, which does not exceed the strain threshold of 500%, and therefore does not satisfy the first requirement. In addition, the shear modulus is 337.6 MPa, which is within the allowable range of shear modulus of 70 to 500 MPa, and therefore satisfies the second requirement. In other words, the strength-bearing structural surface of CASE7 is not the adhesive strength-bearing structural surface of the present invention. And the floor factor is 2.40, which is lower than the floor factor of the conventional technology such as CASE8 (floor factor 3.19) and CASE9 (floor factor 3.92). In this way, even if a load-bearing structural surface is fixed using a combination of adhesive and temporary fixing screws, etc., if it does not satisfy the first and second requirements, it will not be an adhesive-type load-bearing structural surface as defined by the present invention, and its floor multiplier will be a low value.

[0053] 3. Construction method of adhesive bearing structural members Next, the method for constructing an adhesive-type load-bearing structural surface of the present invention will be described with reference to FIG. 12. The method for constructing an adhesive-type load-bearing structural surface of the present invention is the method for constructing the adhesive-type load-bearing structural surface of the present invention that has been described so far. Therefore, we will avoid any overlapping explanation with the contents explained in "2. Adhesive Load-bearing Structural Surfaces" and only explain the contents that are unique to the method for constructing an adhesive-type load-bearing structural surface. In other words, the contents that are not described here are the same as those already explained, including "1. Definitions". The method for constructing an adhesive-type load-bearing structural surface of the present invention can also be implemented in the case of fixing in a square shape, but for convenience, we will explain the case of fixing in a river shape here.

[0054] FIG. 12 is a flow chart showing the flow of the main steps in the method for constructing adhesive load-bearing structural panels of the present invention. As shown in this figure, two main steps are carried out: a design step (Step 100) and a horizontal surface member fixing step (Step 200).

[0055] (design process) In the design process, first, the adhesion specifications of the load-bearing surfaces, i.e., the adhesive specifications, are planned (Step 110). At this time, it is advisable to plan the specifications of the horizontal plane members 100 and the supports 200 as well. Then, a test shown in Fig. 7 (hereinafter simply referred to as a "shear strain test") is conducted on a specimen with the planned adhesion specifications to obtain the shear modulus G, and the above-mentioned in-plane shear test is conducted on the load-bearing surfaces with the planned adhesion specifications, and the resulting displacement characteristic curve is confirmed (Step 120).

[0056] The shear modulus G is obtained by the shear strain test, and the displacement characteristic curve is obtained by the in-plane shear test. Shear strain at 80% of the downward range obtained from the displacement characteristic curve and a distortion threshold value to determine whether the first requirement is met, Shear modulus G and the allowable range of shear modulus of elasticity, and the second requirement is judged (Step 130). At this time, the envelope is obtained based on the in-plane shear test, and the wall factor can also be calculated. Then, when both the first and second requirements are satisfied, the strength-bearing structural surface according to the adhesive specification is judged to be the adhesive-type strength-bearing structural surface of the present invention, and when either the first or second requirement is not satisfied, the strength-bearing structural surface according to the specification is judged to be not the adhesive-type strength-bearing structural surface of the present invention, and the adhesive specification is newly planned (Step 110), and testing and confirmation are performed (Step 120). When the wall factor is calculated, it can also be judged to be the adhesive-type strength-bearing structural surface of the present invention, including the "third requirement" that "the wall factor shows a value equal to or greater than a predetermined wall factor threshold value (for example, the wall factor by the conventional construction method)," that is, when all the first, second, and third requirements are satisfied.

[0057] (Surface material fixing process) In the horizontal member fixing process, first, the end fixing region 110 and the intermediate fixing region 120 are positioned on the back surface (lower surface) of the horizontal member 100 (Step 210), and adhesive is applied to the end fixing region 110 and the intermediate fixing region 120 (Step 220). At this time, if the adhesive-type load-bearing structural panel is in a square shape, the application of adhesive to the intermediate fixing region 120 is omitted. Instead of applying adhesive to the horizontal member 100, adhesive may be applied to the front surface (upper surface) of the support member 200 (Step 220), in which case the positioning process of the end fixing region 110 and the intermediate fixing region 120 (Step 210) can be omitted.

[0058] When adhesive is applied to the end fixing area 110 and the intermediate fixing area 120 (or the surface of the support material 200) on the back surface of the horizontal plane material 100, the horizontal plane material 100 is set up so that the end fixing area 110 and the intermediate fixing area 120 are placed on the support material 200 (Step 230). Then, temporary fixing screws are driven at a specified pitch into the end fixing area 110 and the intermediate fixing area 120 on the surface of the horizontal plane material 100 (Step 240), and after waiting for the adhesive to take effect, the adhesive load-bearing structural surface is completed.

[0059] 4.Adhesive specification decision support program The adhesive specification determination support program of the present invention will be described. Note that the adhesive specification determination support program of the present invention is a program that determines the specifications of the adhesive bearing surface explained so far, and therefore, we will avoid explanations that overlap with the contents explained in "2. Adhesive bearing surface", and only explain the contents unique to the adhesive specification determination support program. Contents not described here are the same as those already explained, including "1. Definitions".

[0060] The adhesive specification determination support program of the present invention is a program that causes a computer to execute a function for determining the specifications of adhesive-type load-bearing structural members, and can be effectively used in the design process of a construction method of adhesive-type load-bearing structural members. More specifically, when an operator inputs the results of a shear strain test and an in-plane shear test according to the planned adhesive specifications, the adhesive specification determination support program of the present invention causes a computer to execute a process for generating a displacement characteristic curve (displacement characteristic curve generation process), a process for calculating a shear strain at 80% of the downward range (shear strain calculation process at 80% of the downward range), and a process for calculating a shear modulus (shear modulus calculation process). At this time, the computer can also execute a process for calculating an envelope based on the in-plane shear test and a process for calculating a wall factor (wall factor calculation process). Then, when both the first and second requirements are satisfied, the computer executes a process (determination process) for determining that the strength-bearing surface based on the adhesive specifications is an adhesive-type strength-bearing surface of the present invention, and when either the first or second requirement is not satisfied, the strength-bearing surface based on the specifications is not an adhesive-type strength-bearing surface of the present invention. When the wall factor is calculated, it can also be determined that the surface is an adhesive-type strength-bearing surface of the present invention, including the "third requirement" that "the wall factor is equal to or greater than a predetermined wall factor threshold value (for example, the wall factor using a conventional construction method)," i.e., when the first, second, and third requirements are all satisfied, the surface is determined to be an adhesive-type strength-bearing surface of the present invention. [Industrial Applicability]

[0061] The adhesive-type load-bearing structural surface, the method for constructing the adhesive-type load-bearing structural surface, and the adhesive specification determination support program of the present invention can be used in various wooden buildings such as detached wooden houses, schools, kindergartens, offices, public facilities, etc. In particular, they are effective for wooden buildings with large spaces such as atriums. [Explanation of symbols]

[0062] 100 Horizontal surface material 100F Floor surface material (horizontal surface material) 100R Roof surface material (horizontal surface material) 110 (horizontal surface material) end fixing area 120 (Horizontal surface material) intermediate fixing area 200 Support material 210 Torso difference (support material) 220 Floor beam (support material) 230 Joists (supporting materials) 240 Purlin material (support material) 250 Rafters (supports) 260 Climbing material (supporting material)

Claims

1. A load-bearing structural surface in which horizontal or inclined surface materials are fixed to structural members or framework members by adhesive, The horizontal or inclined surface material is fixed to the structural member or the frame member with an adhesive specification in which the shear strain at 80% of the downward range in the displacement characteristic curve obtained by performing an in-plane shear test on the adhesive load-bearing structural member is 500% or more, and the shear modulus is 70 MPa or more and 500 MPa or less, The shear strain at 80% of the downward displacement is a value obtained by dividing the 80% downward displacement by the adhesive thickness, The 80% displacement in the descending region is a displacement in the descending region of the displacement characteristic curve among the displacements corresponding to 80% strength of the maximum load of the displacement characteristic curve, The shear modulus is the initial shear force divided by the initial shear strain, The initial shear strain is the initial displacement divided by the adhesive thickness. A bonded load-bearing structural surface characterized by:

2. The structural members or frame members arranged around the horizontal surface material or the inclined surface material, or around and in the center band of the horizontal surface material or the inclined surface material, and the horizontal surface material or the inclined surface material are fixed to each other by the adhesive, A temporary fixing screw or nail is driven into the periphery of the horizontal surface material or the inclined surface material.

2. The adhesive-type load-bearing structural member according to claim 1.

3. The temporary fixing screws or nails are driven at intervals of 300 mm or more.

3. The adhesive-type load-bearing structural member according to claim 2.

4. A method for constructing an adhesive-type load-bearing structural surface in which a horizontal surface material or an inclined surface material is fixed to a structural member or a frame member by an adhesive, comprising the steps of: A design process for determining adhesive specifications including the type of adhesive and adhesive thickness; A surface material fixing process for adhesively fixing the horizontal surface material or the inclined surface material to the structural member or the frame member in accordance with the adhesive specifications determined in the design process, In the design step, the adhesive specifications are determined so that the shear strain at 80% of the descending region is equal to or greater than a predetermined threshold value and the shear modulus is within a predetermined allowable range; The shear strain at 80% of the downward displacement is a value obtained by dividing the 80% downward displacement by the adhesive thickness, The 80% downward displacement is a displacement in a downward region of the displacement characteristic curve among the displacements corresponding to 80% strength of the maximum load of the displacement characteristic curve obtained as a result of performing an in-plane shear test on the adhesive load-bearing structural panel, The shear modulus is the initial shear force divided by the initial shear strain, The initial shear strain is the initial displacement divided by the adhesive thickness. A method for constructing an adhesive load-bearing structural surface.

5. In the surface material fixing step, the structural members or frame members are arranged around the horizontal surface material or the inclined surface material, or around and in a central band of the horizontal surface material or the inclined surface material, and the structural members or frame members and the horizontal surface material or the inclined surface material are fixed to each other by the adhesive, The method further includes a temporary fixing step of driving temporary fixing screws or nails into the periphery of the horizontal surface material or the sloping surface material, or into the periphery and center band of the horizontal surface material or the sloping surface material, in order to temporarily fix the structural member or the frame member and the horizontal surface material or the sloping surface material until the adhesive hardens.

5. The method for constructing an adhesive load-bearing structural panel according to claim 4.

6. A program for causing a computer to execute a function of supporting the determination of adhesive specifications for adhesive-type load-bearing structural members in which horizontal or inclined surface materials are fixed to structural members or frame members by adhesive, The adhesive specification includes the type of adhesive and the adhesive thickness, A displacement characteristic curve generation process for generating a displacement characteristic curve showing the relationship between the displacement and the load obtained as a result of performing an in-plane shear test on the adhesive load-bearing structural member; a shear strain calculation process for calculating a shear strain at 80% of the downward region by dividing an 80% downward displacement amount in the displacement characteristic curve by an adhesive thickness; A shear modulus calculation process for calculating a shear modulus by dividing the initial shear force by the initial shear strain; a determination process for determining, as an appropriate specification, the adhesive specification in which the shear strain at 80% of the descending region is equal to or greater than a predetermined threshold value and the shear modulus is within a predetermined allowable range; The 80% displacement in the descending region is a displacement in the descending region of the displacement characteristic curve among the displacements corresponding to 80% strength of the maximum load of the displacement characteristic curve, The initial shear strain is the initial displacement divided by the adhesive thickness. A bonding specification determination support program.

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