JP6659291B2 - Building board - Google Patents

Description

  The present invention relates to a building board. More specifically, the present invention relates to a building board used for an outer wall of a house or the like.

  Conventionally, as a building board, there is a building board formed of a cured product of a molding material mainly composed of hydraulic inorganic material, and a construction structure in which such building boards are adjacently connected by actual fitting has also been proposed. (For example, see Patent Document 1). On the other hand, the construction board is preferably lighter in consideration of transportability and workability.

  Therefore, as a measure for reducing the weight of a building board, it has been proposed to form a building board using a molding material having a low specific gravity and a molding material having a high specific gravity. In this case, the building board is formed of a core layer and a skin layer, the core layer is formed with a low specific gravity, and the skin layer is formed with a high specific gravity. The skin layer is formed in a structure surrounding the entire core layer. The real part for actual fitting is formed integrally with the skin layer using the same molding material as the skin layer.

JP-A-2002-146993

  However, the skin layer is formed to be relatively thinner than the core layer. Portion) and the skin layer in the vicinity thereof are liable to be damaged such as cracks, and it is difficult to secure the strength of the locking projection.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a building board that can easily secure the strength of a locking projection.

The building board according to the present invention is a building board attached to a building skeleton via a fixture, and includes a flat core layer made of a molding material containing a hydraulic inorganic material, and a hydraulic inorganic material. A skin layer formed of a molding material having a higher absolute dry specific gravity than the molding material forming the layer, and a skin layer formed so as to surround the core layer; comprising a real part and Shitami portion on of a pair of locking projections again and again locking, a respective locking projection is formed the one side edge of each end face in the thickness direction of the building board The upper solid portion is formed to project from an upper skin layer of a pair of opposite end surfaces of the skin layer, and the lower solid portion is formed on a lower skin layer of a pair of opposite end surfaces of the skin layer. It formed to protrude, in the thickness direction of the a real part Kicking dimensions, the is formed smaller than the vertical dimension of the perpendicular to the thickness direction of the top skin layer, the dimension in the thickness direction of the base end portion of the lower real part, the thickness of the lower surface skin layer that is smaller than the vertical dimension perpendicular to the direction, characterized in that.

  ADVANTAGE OF THE INVENTION According to this invention, breakage of the locking projection due to wind pressure is less likely to occur, and the strength of the locking projection is easily ensured.

FIG. 1 is a front view showing an embodiment of the present invention. FIG. 2 is a sectional view showing an embodiment of the present invention. FIG. 3 is a cross-sectional view showing a construction state according to the embodiment of the present invention. FIG. 4A is a front view showing a fixture that can be used in the embodiment of the present invention. FIG. 4B is a side view showing a fixture usable in the embodiment of the present invention. FIG. 5 is a schematic diagram showing an extruder that can be used for manufacturing the embodiment of the present invention. FIG. 6 is a cross-sectional view showing a mold that can be used for manufacturing the embodiment of the present invention. FIG. 7A is a plan view schematically showing a hollow molded body that can be used for manufacturing the embodiment of the present invention. FIG. 7B is a side view schematically showing the hollow molded article shown in FIG. 7A. FIG. 8A is a plan view showing a state where two test pieces are butted. FIG. 8B is a cross-sectional view showing a state where the two test pieces shown in FIG. 8A are connected by a fixture. FIG. 8C is a plan view of the two specimens shown in FIG. 8B.

  Hereinafter, embodiments for implementing the present invention will be described.

  The building board 1 shown in FIG. 1 is for forming an outer wall or the like, and is formed in a horizontally long substantially rectangular shape when viewed from the front (view from the outdoor side with the building board 1 installed). . Accordingly, the upper side and the lower side of the building board 1 are formed as long sides, and the one side and the other side are formed as short sides. Most of the building board 1 is formed as a horizontally long, substantially rectangular exterior part 20. The exterior part 20 is formed with a real part 12 and a cover part (cover part) 13, whereby the building board 1 is formed in a quadrilateral shape.

  As the real part 12, an upper real part 121 and a side real part 123 are provided. The solid part 121 is provided along substantially the entire length of the upper side of the building board 1. The solid part 121 is provided so as to protrude above the upper end of the exterior part 20. The side real part 123 is provided along substantially the entire length of one side of the building board 1. The side real part 123 is provided to protrude outward from one side end of the exterior part 20.

  As the covering portion 13, a lower covering portion 131 and a side covering portion 132 are provided. The lower cover 131 is provided along substantially the entire length of the lower side of the building board 1. The lower cover portion 131 is provided so as to protrude below the lower end of the exterior portion 20. The side covering portion 132 is provided along substantially the entire length of the other side of the building board 1 (the side where the real side portion 123 is not provided). The side covering portion 132 is provided so as to protrude outward from the other side end of the exterior portion 20 (side end where the side real portion 123 is not provided).

  FIG. 2 is a sectional view of the building board 1. The building board 1 includes a core layer 2 and a skin layer 3. The core layer 2 is formed in a plate shape. A plurality of hollow holes 21 are formed in the core layer 2 to reduce the weight of the building board 1. The hollow holes 21 are formed to be long substantially in parallel with the longitudinal direction of the building board 1, and the plurality of hollow holes 21 are provided side by side in the short direction of the core layer 2. The skin layer 3 is formed so as to surround the core layer 2. That is, the skin layer 3 includes an upper skin layer 31 that forms the upper surface of the exterior part 20, a lower skin layer 32 that forms the lower surface of the exterior part 20, a surface skin layer 33 that forms the surface of the exterior part 20, 20 and a back skin layer 34 forming the back surface, and both end faces (faces on the edge side) of the core layer 2 are not covered.

  The solid part 121 is formed to protrude from the upper surface of the upper skin layer 31. The solid part 121 and the upper skin layer 31 are integrally formed of the same molding material. The thickness of the solid portion 121 is formed to be approximately half the thickness of the building board 1 and is formed closer to the back side in the thickness direction of the building board 1 (the back end of the upper end face of the building board 1 in the thickness direction of the building board 1). Have been. The lower cover portion 131 is formed to protrude from the lower surface of the lower skin layer 32. The lower cover 131 and the lower skin layer 32 are integrally formed of the same molding material. The thickness of the lower cover portion 131 is formed to be approximately half the thickness of the building board 1, and is formed closer to the front side in the thickness direction of the building board 1.

  A lower solid part 122 is provided at a lower end of the building board 1. The lower solid part 122 is provided along substantially the entire length of the lower side of the building board 1. The lower solid part 122 is formed to protrude from the lower surface of the lower skin layer 32. The lower solid portion 122 and the lower skin layer 32 are integrally formed of the same molding material. Further, the thickness of the lower solid portion 122 is formed to be approximately half the thickness of the building board 1 and is formed closer to the back side in the thickness direction of the building board 1 (the back end of the lower end face of the building board 1 in the thickness direction of the building board 1). Have been. The lower solid part 122 is provided at the lower end of the exterior part 20 so as to protrude downward. The projecting length of the lower solid portion 122 from the lower surface skin layer 32 is smaller than the projecting length of the lower cover portion 131 from the lower surface skin layer 32. Therefore, the lower end of the lower solid part 122 is located above the lower covering part 131. The lower solid part 122 is hidden behind the lower covering part 131 and cannot be visually recognized when the building board 1 is viewed from the front.

  Although not shown, both side end surfaces of the core layer 2 are also covered with the skin layer 3. At one side end of the building board 1, a side real part 123 is formed so as to protrude from the surface of the skin layer 3. The side part 123 and the skin layer 3 are integrally formed of the same molding material. The thickness of the side real part 123 is formed to be approximately half the thickness of the building board 1, and is formed closer to the back side in the thickness direction of the building board 1. At the other side end of the building board 1, a side cover 132 is formed so as to protrude from the surface of the skin layer 3. The side cover 132 and the skin layer 3 are integrally formed of the same molding material. The thickness of the side covering portion 132 is formed to be approximately half of the thickness of the building board 1, and is formed closer to the front side in the thickness direction of the building board 1.

  The building board 1 has a pair of real parts 12 formed by an upper real part 121 and a lower real part 122. The upper real part 121 and the lower real part 122 are formed as locking projections which are locked to the attachment 5 described later.

  The upper real part 121, which is one of the pair of real parts 12, is formed such that the dimension T6 in the thickness direction of the building board 1 is smaller than the thickness T2 of the skin layer 3 near the upper real part 121. Here, the thickness T2 of the skin layer 3 near the solid part 121 is the thickness of the upper skin layer 31 below the solid part 121 (the dimension from the upper end surface of the core layer 2 to the upper surface of the upper skin layer 31). ) T2 (see FIG. 2). Therefore, the dimension T6 of the solid portion 121 in the thickness direction of the building board 1 and the thickness T2 of the upper skin layer 31 satisfy the relationship of T6 <T2.

  The base end of the lower real part 122 which is the other of the pair of real parts 12 is formed such that the dimension T5 in the thickness direction of the building board 1 is smaller than the thickness T1 of the skin layer 3 near the lower real part 122. Have been. Here, the thickness T1 of the skin layer 3 near the lower solid portion 122 is the thickness of the lower skin layer 32 above the lower solid portion 122 (the dimension from the lower end surface of the core layer 2 to the lower surface of the lower skin layer 32). ) T1 (see FIG. 2). Therefore, the thickness T5 of the lower solid portion 122 and the thickness T1 of the lower skin layer 32 satisfy the relationship of T5 <T1.

  As described above, the building board 1 satisfies the relationship of T6 <T2 or the relationship of T5 <T1, so that even if it is subjected to wind pressure after being constructed as a wall plate or the like, the real part 12 (upper real part) The skin layer 3 (the upper skin layer 31 and the lower skin layer 32) in and near the lower part 121 and the lower solid part 122) is less likely to be damaged, and the strength of the real part 12 is easily ensured. This is because when T5 <T1 and T6 <T2, the core layer 2 having a lower specific gravity than the skin layer 3 is less susceptible to damage and harder to break.

  The thickness T2 of the upper skin layer 31 and the thickness T1 of the lower skin layer 32 are preferably 5 mm or more, and more preferably 10 mm or more. The thickness T1 and the thickness T2 are preferably equal to or less than 50 mm. The thickness T3 of the front skin layer 33 and the thickness T4 of the back skin layer 34 are preferably 1 mm or more. It is preferable that the thickness T3 and the thickness T4 be equal to or less than 1/3 of the thickness of the entire building board 1. The dimension T5 of the base end of the lower solid portion 122 in the thickness direction of the building board 1 is not particularly limited as long as it is smaller than T1, but is preferably, for example, 7 mm or more. In this case, T1 is formed to be larger than 7 mm. Is done. The dimension T6 of the solid portion 121 in the thickness direction of the building board 1 is not particularly limited as long as it is smaller than T2, but is preferably, for example, 6 mm or more. In this case, T2 is formed to be larger than 6 mm. The thickness T7 of the lower cover 131 is preferably, for example, 3 mm or more. By setting the sizes of the thicknesses T1, T2, T5, and T6 in this manner, the strength of the upper solid portion 121 and the lower solid portion 122, the upper skin layer 31, and the lower skin layer 32 can be easily secured, and the cutting process can be performed. Thereby, the upper solid part 121 and the lower solid part 122 are easily formed.

  FIG. 3 shows a state where the building board 1 is constructed. The building board 1 is constructed by arranging a plurality of the boards in a matrix, and for example, an outer wall is formed. The building board 1 is attached to a wall foundation (building body) 6 such as a pillar or a rim by a plurality of fixtures 5 and is constructed.

  As shown in FIGS. 4A and 4B, the fixture 5 includes a fixing plate 50, a horizontal piece 51, a receiving claw 52, a holding claw 53, a projecting piece 54, an inward piece 55, and an outward piece 56. And The horizontal piece 51, the receiving claw 52, the holding claw 53, the protruding piece 54, the inward piece 55, and the outward piece 56 can be formed by cutting and raising a part of the fixing plate 50. The fixing plate 50 is provided with a fixing hole 57. The fixture 5 is fixed to the wall base 6 by driving nails, screws, screws, and the like into the wall base 6 through the fixing holes 57.

As shown in FIG. 4B, the horizontal pieces 51 protrude from the fixed plate 50 in a direction orthogonal to the horizontal direction. Since the horizontal piece 51 is formed by cutting and raising the fixed plate 50, an opening 58 is provided below the fixed plate 50 (see FIG. 4A).

  As shown in FIGS. 4A and 4B, the receiving claw 52 protrudes from the tip of the horizontal piece 51 in a direction crossing the horizontal piece 51. The receiving claw 52 is provided over substantially the entire length of the horizontal piece 51 in the left-right direction without being divided. The width X of the receiving claw 52 shown in FIG. 4A is preferably, for example, 66 mm or more.

  As shown in FIGS. 4A and 4B, the holding claw 53 protrudes from the tip of the horizontal piece 51 in a direction crossing the horizontal piece 51. The holding claw 53 projects to the opposite side of the receiving claw 52. The holding claw 53 is divided into two. The width Y between both ends of the holding claw 53 shown in FIG. 4A is preferably, for example, 44 mm or more.

  The protruding pieces 54 protrude forward from both left and right ends of the fixed plate 50. The projecting length of the projecting piece 54 is shorter than the projecting length of the horizontal piece 51. The inward piece 55 is provided on the inside from the tip of the protruding piece 54 substantially parallel to the fixing plate 50, and the outward piece 8 is provided on the outside from the tip of the protruding piece 54 substantially parallel to the fixing plate 50.

  The upper solid portion 121 of the lower building board 1 of the two vertically adjacent building boards 1 is interposed and locked between the holding claw 53 of the fixture 5 and the outward piece 56. . The lower solid portion 122 of the upper building board 1 of the two vertically adjacent building boards 1 is interposed and locked between the receiving claw 52 of the fixture 5 and the outward piece 56. Thereby, the solid part 121 of the lower building board 1 and the solid part 122 of the upper building board 1 are connected via the attachment 5. Further, the receiving claw 52, the holding claw 53, and the upper solid portion 121 of the lower building board 1 are covered with the lower covering portion 131 of the upper building board 1 and cannot be seen from the front side.

  Since the solid portion 121 of the construction board 1 constructed in this manner is hooked (locked) by the holding claw 53, when wind pressure acts on the construction board 1, the solid portion 121 and the peripheral portion thereof are formed. Although a load is applied, a load is not easily applied to a part of the core layer 2 near the solid portion 121 because of the relationship of T6 <T2, and the solid portion (locking projection) 121 and the upper skin layer 31 Cracks and other damage are less likely to occur. Further, since the lower solid portion 122 of the constructed building board 1 is hooked (locked) by the receiving claw 52, when wind pressure acts on the building board 1, a load is applied to the lower solid portion 122 and its peripheral portion. However, since the relationship of T5 <T1 is satisfied, it is difficult to apply a load to a part of the core layer 2 near the lower solid portion 122, and the lower solid portion (locking protrusion) 122 and the lower skin layer 32 It is hard to cause damage such as cracks.

  Although not shown, the two building boards 1 to be constructed adjacent to each other on the left and right have a surface covering portion 132 of the other building board 1 on the surface of the side real part 123 of the one building board 1. Can be stacked. Thereby, two building boards 1 constructed adjacently on the left and right are connected.

  The core layer 2 is formed from a cured product of a molding material containing a hydraulic inorganic material (hereinafter, sometimes referred to as a core material). The skin layer 3 is formed from a cured product of a molding material containing a hydraulic inorganic material (hereinafter, sometimes referred to as a skin material). The core material and the skin material are different from each other in the composition of the hydraulic inorganic material. The real part 12 and the cover part 13 are formed of a cured product of the same molding material as the skin material.

  Comparing the absolute dry specific gravity of the core layer 2 and the absolute dry specific gravity of the skin layer 3, the absolute dry specific gravity of the skin layer 3 is larger than the absolute dry specific gravity of the core layer 2. Accordingly, the weight of the core layer 2 is reduced and the weight of the entire building board 1 is reduced, and the skin layer 3 has a higher density than the core layer 2 and the strength of the skin layer 3 is higher than that of the core layer 2. Cheap.

  The absolute dry specific gravity of the skin layer 3 is preferably 0.8 or more. Thereby, the strength of the skin layer 3 can be easily secured. Further, it is preferable that the absolute dry specific gravity of the skin layer 3 is 0.8 or more and 2.0 or less, and the absolute dry specific gravity of the core layer 2 is 0.7 or more and less than 2.0. In this case, the weight reduction of the whole building board 1 by the weight reduction of the core layer 2 and the ensuring of the intensity | strength of the skin layer 3 become compatible easily, and wind resistance performance of the building board 1 becomes easy to ensure. In particular, when the absolute specific gravity of the skin layer 3 is 0.8 or more, the strength of the skin layer 3 is sufficiently secured, so that the upper solid portion 121 and the lower solid portion 122 are not easily damaged.

  The bending strength of the cured product of the skin material is preferably 5 MPa or more. Thereby, the strength of the skin layer 3 is easily secured sufficiently. The bending strength of the cured product of the molding material forming the skin layer 3 is such that a molded product having a width of 50 mm, a length of 60 mm, and a thickness of 5 mm is cut out from the upper solid portion 121 or the lower solid portion 122, and this molded product is obtained by an autograph. It is derived by performing a bending test at a span of 10 mm / min and 50 mm. The bending strength of the cured product of the skin material can be adjusted to 5 MPa or more by an appropriate method such as selection of components contained in the skin material and adjustment of the amount of the components.

  The core material and the skin material contain, for example, an inorganic main material, an inorganic admixture, an organic admixture, reinforcing fibers, water, and additives.

  The inorganic main material is made of a compound containing at least one of silicon and calcium. The inorganic main material mainly contains cement, which is a hydraulic inorganic material. The inorganic base material may further contain one or more materials selected from the group consisting of fly ash, silica fume, and silica powder.

  The inorganic admixture includes, for example, mica, sodium silicate and the like.

  The organic admixture includes, for example, methylcellulose, organic foamed particles, and the like. The organic foamed particles can contain, for example, one or more materials selected from the group consisting of styrene resins, vinylidene chloride resins, and acrylonitrile resins.

  The reinforcing fibers include, for example, pulp and polypropylene fibers.

  The core material and the skin material may further contain an inorganic foam in addition to the above-mentioned raw materials. The inorganic foam can contain, for example, one or more materials selected from the group consisting of perlite, fly ash balloon, and vermiculite.

  The proportion of each substance contained in the core material is not particularly limited. For example, the core material contains 73 to 97% by weight of an inorganic main material, the inorganic material contains 1 to 20% by weight of an inorganic admixture, and the organic material contains It is preferable that the admixture is contained in the range of 1 to 3.5% by weight and the reinforcing fiber is contained in the range of 1 to 3.5% by weight.

  Although the proportion of each substance contained in the skin material is not particularly limited, for example, the calcium silicate compound is in the range of 69.5 to 97.5% by weight, and the inorganic admixture is in the range of 1 to 20% by weight. Of these, it is preferable that the organic admixture is contained in the range of 1 to 3.5% by weight and the reinforcing fiber is contained in the range of 1 to 7% by weight. The absolute specific gravity of the core layer 2 and the skin layer 3 can be adjusted by, for example, changing the proportion of water contained in the core material and the skin material and the proportion of the organic foam.

  Hereinafter, a method for manufacturing the building board 1 will be described.

  FIG. 5 shows an outline of an extruder 10 for manufacturing the building board 1. The extruder 10 extrudes a core material and a skin material. The extruder 10 includes a first extruder 25 and a second extruder 26. The first extruder 25 extrudes the skin material, and the second extruder 26 extrudes the core material. The first extruder 25 and the second extruder 26 are connected to the mold 100. The mold 100 has an inflow port 103 at the front end and an extrusion port 104 at the rear end. The inflow port 103 is connected to the first extruder 25. Therefore, the skin material flows into the inflow port 103 from the first extruder 25.

  FIG. 6 is a schematic sectional view of the mold 100. The mold 100 includes an upper mold 101, a lower mold 102, a core 105, a flow path 106, a flow path 107, and a flow path 108. The upper die 101 and the lower die 102 are vertically opposed to each other.

  A cavity is formed inside the mold 100. A core 105 is provided in this cavity. The flow path 106 is between the lower surface of the upper die 101 and the upper surface of the core 105 appearing in the sectional view of FIG. 6, and the flow path 107 is between the upper surface of the lower die 102 and the lower surface of the core 105. It is. The channel 106 and the channel 107 are connected to the inlet 103. Therefore, the skin material flows through the flow path 106 and the flow path 107.

  As shown in the cross-sectional view of FIG. 6, the core 105 gradually decreases in thickness from the vicinity of the inlet 103 toward the inlet 103. Further, the end of the core 105 on the side of the extrusion port 104 gradually decreases in thickness toward the extrusion port 104. The tip of the core 105 on the side of the extrusion port 104 is disposed so as to face the extrusion port 104. The upper surface of the distal end of the core 105 is formed as a flat inclined surface 111 toward the distal end, and the lower surface of the distal end of the core 105 is formed as a flat inclined surface 112 toward the distal end.

  As shown in the sectional view of FIG. 6, a flow path 108 is formed inside the core 105. This flow path 108 is connected to the second extruder 26. Specifically, the flow path 108 in the core 105 is connected to the second extruder 26 via the pipe 17. For this reason, the core material kneaded by the second extruder 26 flows into the channel 108. A rectangular opening 110 communicating with the flow path 108 is formed at the tip of the core 105.

  As shown in the cross-sectional view of FIG. 6, these flow channels 106, 107, and 108 are provided on the extrusion port 104 side with respect to the flow channels 106 and 107 in the mold 100. They meet at section 109. For this reason, the extrusion port 104 is connected to the flow path 106, the flow path 107, and the flow path 108.

  Further, a hollow forming body 200 as shown in FIGS. 7A and 7B is provided in the flow path 108. The hollow formed body 200 includes a main body 201 and a plurality of projecting bars 202. The plurality of projecting bars 202 are arranged in a line at a predetermined interval and are provided in parallel with each other. The dimensions of the plurality of protruding bars 202 are all the same. The hollow formed body 200 has a size that can be arranged inside the flow path 108. The hollow forming body 200 is provided in the flow path 108 of the core 105, and a part of the plurality of protruding rods 202 protrudes from the opening 110. A core 105 having a hollow formed body 200 provided in a flow path 108 is provided in a mold 100 and is extruded using the mold 100 to form an uncured formed body having a hollow hole 21 (green sheet). ) Is manufactured.

  In manufacturing the building board 1 using the extruder 10, first, the skin material is charged into the input port 27 of the first extruder 25 and the core material is supplied into the input port 15 of the second extruder 26. The skin material and the core material are conveyed while being kneaded by the screw 14 provided in the first extruder 25 and the screw 16 provided in the second extruder 26, respectively. Thereafter, the core material flows from the second extruder 26 into the flow path 108 via the pipe 17. Further, the skin material flows from the first extruder 25 through the inlet 103 into the flow channels 106 and 107.

  Next, the core material passing through the flow path 108 reaches the opening 110. The core material discharged from the opening 110 is formed into a plate shape according to the shape of the opening 110. Further, the skin material passing through the flow path 106 and the skin material passing through the flow path 107 merge at the junction 109. Thus, the outside of the plate-shaped core material is wrapped by the skin material.

  Next, the core material and the skin material are extruded from the extrusion port 104 while the core material is wrapped by the skin material. By cutting the core material and the skin material at an arbitrary length, an uncured molded body (green sheet) is formed.

  Next, the core layer 2 and the skin layer 3 are formed by curing and curing the uncured molded body. In the step of curing the uncured molded body, for example, one or more types of curing selected from the group consisting of room temperature curing, steam curing, and autoclave curing are performed. In the present embodiment, it is particularly preferable to perform steam curing. The conditions for the steam curing are, for example, preferably such that the temperature is in the range of 40 to 90 ° C. and the curing time is in the range of 6 to 48 hours.

  Next, the cured molded body is dried. The drying method is not particularly limited, and examples thereof include hot air drying and far-infrared drying. By drying the cured molded article, the proportion of water (water content) contained in the molded article can be adjusted. The water content of the molded body is preferably in the range of 3 to 20%. In this case, the molded body can be made light and hard to break, and deformation such as warpage and shrinkage due to drying and shrinkage of the molded body can be reduced.

  Next, the real part 12 and the cover part 13 are formed on the dried molded body. The real part 12 and the cover part 13 can be formed, for example, by cutting a part of the skin layer 3 at the upper end, the lower end, and the side end of the dried molded body.

  In the building board 1, the interface between the core layer 2 and the skin layer 3 may have an uneven shape. The uneven shape may be, for example, unevenness in which a plurality of square irregularities are arranged in a cross section, or may be a zigzag shape in which a plurality of triangular irregularities are arranged in a cross section, and a plurality of arc-shaped irregularities are arranged in a cross section. It may have a wave shape. In this case, the occurrence of delamination between the core layer 2 and the skin layer 3 due to the frost damage phenomenon can be suppressed. Further, a sealer and a paint for surface finishing may be applied to the surface of the building board 1, that is, the surface of the skin layer 3 as necessary.

  Hereinafter, the present invention will be described specifically with reference to Examples.

(Examples 1 and 2 and Comparative Examples 1 and 2)
A core material and a skin material were prepared by blending the inorganic main material, the inorganic admixture, the organic admixture, the reinforcing fibers, and water in the proportions shown in Table 1 below. The water content in Table 1 is the ratio of water to the total solid content in each of the core material and the skin material.

  The core material and the skin material described above were molded using the first extruder 25, the second extruder 26, and the extruder 10 including the mold 100 shown in FIG. 5 to produce an uncured molded body. . The uncured molded body is steam-cured and cured at 60 ° C. for 24 hours to form a molding having a width of 480 mm, a length of 3100 mm, and a thickness of 16 mm, and having the core layer 2 and the skin layer 3. I got a body. Next, after the cured molded body was adjusted to a moisture content of 10% by a dryer, the opposite long sides of the cured molded body were subjected to cutting to form the real part 12 and the cover part 13. Thus, the building board 1 shown in FIGS. 1 and 2 was obtained. Table 1 shows T1, T2, T5, and T6 for this building board 1. Further, T3 and T4 are each 2 mm, and T7 is 8 mm. Two pieces of the building board 1 of each example and each comparative example were prepared.

(Evaluation)
<Bending strength of cured skin material>
The skin materials of Examples 1 and 2 and Comparative Examples 1 and 2 were molded, steam-cured at 60 ° C. for 24 hours, and then adjusted to a moisture content of 10% with a dryer. Thus, a molded body having a width of 50 mm, a length of 60 mm, and a thickness of 5 mm was produced. The molded product was subjected to a bending test by an autograph. The test speed of the bending test was 10 mm / min, and the span was 50 mm. The results are shown in Table 1 below.

<Body specific gravity>
The absolute dry specific gravity of the core layer 2 and the skin layer 3 of the building board 1 was measured by the Archimedes method. The results are shown in Table 1 below.

<Fitting tool pull-out test>
Of the two building boards 1, one of the building boards 1 was cut into dimensions of 100 mm in width and 200 mm in length except for its lower part, to produce a test piece S1. In addition, the other building board 1 of the two building boards 1 was cut into dimensions of 100 mm in width and 200 mm in length, leaving the upper part thereof, to produce a test piece S2.

  The lower solid part 122 and the upper solid part 121 of these two types of specimens S1 and S2 are butted and connected as shown in FIG. 8A, and the lower solid part 122 and the lower solid part 122 of the two specimens S1 and S2 are further connected. The part 121 was connected with the fixture 5 as shown in FIG. 8B. In addition, as shown in FIG. 8C, the attachment 5 was installed at the center of the lower solid portion 122 and the upper solid portion 121 in the longitudinal direction. Then, with the two test pieces S1 and S2 connected by the fixture 5 fixed, the fixture 5 is pulled in the direction D shown in FIG. 8B using an autograph, and the fixture 5 is pulled out. Was measured and the value of this force was taken as the fixture holding force.

The general construction height of ceramic siding is 13 m or less, and the wind load in an area with a height of 13 m and a wind speed of 46 m / s is −1955.6 N / m ^{2 according} to the calculation formula of the Ministry of Land, Infrastructure, Transport and Tourism Notification 1458. . In the case where the pitch of the fixture (interval between the plurality of fixtures) is 455 mm and the working width of the siding is 455 mm, the necessary holding force that can withstand the wind load is 405 N or more.

  From this, the case where the holding force of the fixture 5 was 405 N or more was judged as pass, and the case where the holding force was less than 405 N was judged as reject. Table 1 below shows the results of measuring the fixture holding force and the determination results for the test pieces S1 and S2 obtained from the building boards 1 of Examples 1 and 2 and Comparative Examples 1 and 2.

DESCRIPTION OF SYMBOLS 1 Building board 2 Core layer 3 Skin layer 5 Fixture 6 Wall base (building frame)
121 Solid part (locking projection)
122 Lower solid part (locking projection)
T1, T2 thickness T5, T6 dimensions

Claims (3)

An architectural board attached to a building frame via a fixture,
A flat core layer made of a molding material containing a hydraulic inorganic material,
A skin layer containing a hydraulic inorganic material and having a higher absolute dry specific gravity than the molding material forming the core layer, and formed so as to surround the core layer;
The skin layer is respectively protrude on a pair of end faces opposed to the, and a real and Shitami portion on of a pair of locking projections for locking the fitting,
Each of the locking projections is formed at one end of each of the end faces in the thickness direction of the building board,
The solid portion is formed to project from an upper skin layer of a pair of opposed end faces of the skin layer,
The lower solid portion is formed so as to protrude from a lower surface skin layer of a pair of opposed end surfaces of the skin layer,
The dimension in the thickness direction of the solid portion is formed smaller than the dimension in the vertical direction orthogonal to the thickness direction of the upper skin layer ,
Dimension in the thickness direction of the base end portion of the lower real part, that is smaller than the vertical dimension perpendicular to the thickness direction of the bottom surface skin layer,
An architectural board characterized by that.   The building board is cut into dimensions of 100 mm in width and 200 mm in length to produce two specimens, and the lower real part and the upper real part of the two test bodies are connected by abutting and the lower real part is connected. The part and the solid part are connected by the mounting tool, and in a state where the two test pieces connected by the mounting tool are fixed, the mounting tool is orthogonal to the surface of the test piece using an autograph. In the direction away from the test body in the direction in which the mounting fixture is pulled out, and the value of this force is 405 N or more.
The building board according to claim 1.   The core layer includes a plurality of hollow holes extending in a left-right direction orthogonal to the thickness direction,
The building board according to claim 1.

Images