Manufacturing device for structural member and manufacturing method for structural member

Abstract

To provide a manufacturing device for a structural member and a manufacturing method for a structural member which can form the side surface of a structural member manufactured by laminating a hydraulic mixture into any shape without increasing the number of processes.SOLUTION: A manufacturing device for a structural member includes a nozzle 4 for discharging a hydraulic mixture 2 and a moving part 5 for moving the nozzle 4, a nozzle opening 41 of the nozzle 4 has a trapezoidal shape, and a first edge part 421 corresponding to an upper bottom of a trapezoid is set longer than a second edge part 422 corresponding to a lower bottom of the trapezoid, the moving part 5 moves the nozzle 4 so that a surface 22 formed by the hydraulic mixture 2, discharged from the nozzle 4, coming into contact with a first edge part 421 becomes an upper surface and a surface 21 formed by coming into contact with the second edge part 422 becomes a lower surface, and moves the nozzle 4 so that the hydraulic mixture 2 discharged from the nozzle 4 is laminated from a lower side to an upper side.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a manufacturing apparatus for structural members and a method for manufacturing structural members.

Background Art

[0002] In recent years, an additive manufacturing technique for forming a structural member while laminating cement-based materials has been proposed. For example, the additive manufacturing apparatuses disclosed in Patent Documents 1 and 2 form a structural member by laminating a cement-based material discharged from a nozzle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] When laminating a cement-based material discharged from the nozzle of an additive manufacturing apparatus, unevenness between the layers laminated on the side surface may remain, resulting in a non-smooth surface and stripe patterns. Therefore, when there are problems with the aesthetics and dimensional accuracy of a structural member with stripe patterns formed on its side surface, it is necessary to add processes such as polishing the side surface. Patent Document 2 discloses a method for smoothing the side surface by bringing a cement-based material into contact with a side member provided on the side when laminating a cement-based material discharged from the nozzle of an additive manufacturing apparatus. However, the number of processes such as manufacturing and removing the side member increases, and the construction work becomes complicated.

[0005] On the other hand, when using a structural member manufactured by an additive manufacturing apparatus as a buried formwork, it may be considered to deliberately form unevenness on the side surface of the buried formwork in order to improve the adhesion between the buried formwork and the concrete placed in the buried formwork.

[0006] Therefore, an object of the present invention is to provide a manufacturing apparatus for a structural member and a manufacturing method for a structural member, which can form the side surface of the structural member manufactured by laminating a hydraulic mixture into an arbitrary shape without increasing the number of steps.

Means for Solving the Problems

[0007] To achieve the above object, a manufacturing apparatus for a structural member according to the present invention includes a nozzle for discharging a hydraulic mixture and a moving unit for moving the nozzle. The nozzle opening of the nozzle has a trapezoidal shape, and a first edge corresponding to the upper base of the trapezoid is set to be longer than a second edge corresponding to the lower base of the trapezoid. The moving unit moves the nozzle so that the surface formed by the hydraulic mixture discharged from the nozzle in contact with the first edge becomes the upper surface, and the surface formed by the hydraulic mixture discharged from the nozzle in contact with the second edge becomes the lower surface, and moves the nozzle so that the hydraulic mixture discharged from the nozzle is laminated from the lower side to the upper side.

[0008] To achieve the above object, a manufacturing method for a structural member according to the present invention moves a nozzle for discharging a hydraulic mixture to laminate the hydraulic mixture discharged from the nozzle from the lower side to the upper side. The nozzle opening of the nozzle has a trapezoidal shape, and a first edge corresponding to the upper base of the trapezoid is set to be longer than a second edge corresponding to the lower base of the trapezoid. The moving unit moves the nozzle so that the first surface formed by the hydraulic mixture discharged from the nozzle in contact with the first edge becomes the upper surface, and the second surface formed by the hydraulic mixture discharged from the nozzle in contact with the second edge becomes the lower surface.

[0009] In the manufacturing apparatus for a structural member and the manufacturing method for a structural member according to the present invention, the first surface formed by the hydraulic mixture discharged from the nozzle in contact with the first edge becomes the upper surface, and the second surface formed by the hydraulic mixture discharged from the nozzle in contact with the second edge becomes the lower surface. That is, the width dimension of the lower part of the hydraulic mixture discharged from the nozzle 4 is smaller than the width dimension of the upper part. When a new layer of a hydraulic mixture is laminated on top of an already formed layer of the hydraulic mixture, the lower layer is crushed by the weight of the upper layer. The lower layer is crushed so that the lower part spreads wider in the width direction than the upper part. At this time, by adjusting the trapezoidal shape of the opening of the nozzle orifice, the lower part and the upper part of the crushed layer can be made to have substantially the same width dimension. As a result, the cross-sectional shape of the crushed lower layer becomes substantially rectangular. Furthermore, when lamination is performed, each layer is crushed by the weight of the upper layer, and the cross-sectional shape changes from trapezoidal to rectangular. Thereby, the upper part of the lower layer and the lower part of the upper layer have substantially the same width dimension, no unevenness is formed between the lower layer and the upper layer, and the side surface of the structural member manufactured by laminating the hydraulic mixture becomes smooth. Also, by adjusting the trapezoidal shape of the opening of the nozzle orifice, the width dimension of the upper part of the crushed layer can be made larger than the width dimension of the lower part, and the cross-sectional shape of each layer can be made into a trapezoid with the upper base longer than the lower base. The surface corresponding to the hypotenuse of the trapezoid of the cross-sectional shape of each layer becomes an inclined surface that gradually slopes inward in the width direction from the upper side to the lower side. And below the inclined surface, the upper surface of the lower layer is arranged in a state of protruding outward in the width direction from the lower end position of the inclined surface. As a result, unevenness is formed on the side surface of the structural member manufactured by laminating the hydraulic mixture by alternately arranging the upper surface of the lower layer and the inclined surface of the side surface of the upper layer. When filling a material such as concrete or a joint material along the side surface of the structural member, the material that has entered the concave portion on the side surface of the structural member is in a state of being placed on the upper surface of the lower layer that forms the concave portion and is filled in the concave portion in a stable state. Also, even if the material filled in the concave portion protrudes from the concave portion, the material filled in the inside of the concave portion remains in the concave portion in a stable state, resulting in a structure that is difficult to fall downward. As a result, the workability when filling the material along the side surface of the structural member is good. In the manufacturing apparatus and method for a structural member according to the present invention, in order to smooth the side surfaces of the stacked hydraulic mixtures, there is no need to polish them or install temporary members for pressing the side surfaces to smooth the side surfaces during stacking. Thus, in the manufacturing apparatus and method for a structural member according to the present invention, the side surfaces of the structural member manufactured by stacking the hydraulic mixtures can be smoothed without increasing the number of steps.

[0010] In the manufacturing apparatus for a structural member according to the present invention, the nozzle opening may be opened downward, and the moving unit may move the nozzle such that the second edge of the nozzle opening is disposed on the front side in the moving direction of the nozzle with respect to the first edge.

[0011] With such a configuration, the hydraulic mixture discharged from the nozzle can be formed in a direction in which the first surface formed in contact with the first edge becomes the upper surface and the second surface formed in contact with the second edge becomes the lower surface.

[0012] In the manufacturing apparatus for a structural member according to the present invention, among the two hypotenuses of the trapezoid of the opening shape of the nozzle opening, the third edge corresponding to one hypotenuse and the fourth edge corresponding to the other hypotenuse may each have a different angle with the first edge.

[0013] With such a configuration, the side surfaces on one side and the other side of the structural member manufactured by stacking layers of the hydraulic structure can be made to have different shapes. For example, one side surface can be made a flat surface and the other side surface can be made a concave-convex surface.

[0014] In the manufacturing method for a structural member according to the present invention, concavities and convexities corresponding to the corner formed by the surface corresponding to the hypotenuse of the trapezoid of the opening shape of the nozzle opening and the first surface may be formed on the side surface of the structural member manufactured by stacking the layers of the hydraulic mixture discharged from the nozzle opening from the lower side toward the upper side.

[0015] With such a configuration, concavities and convexities can be easily formed on the side surface of the structural member manufactured by stacking the hydraulic mixture.

Advantages of the Invention

[0016] According to the present invention, the side surface of a structural member manufactured by laminating a hydraulic mixture can be formed into an arbitrary shape without increasing the number of steps.

Brief Description of the Drawings

[0017]

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Mode for Carrying Out the Invention

[0018] Hereinafter, a manufacturing apparatus for a structural member and a manufacturing method for a structural member according to an embodiment of the present invention will be described with reference to FIGS. 1-10. As shown in FIG. 1, a manufacturing apparatus 1 for a structural member according to the present embodiment is an additive manufacturing apparatus that manufactures a structural member 3 by laminating a hydraulic mixture 2 such as mortar, cement, or concrete. The manufacturing apparatus 1 for a structural member includes a nozzle 4 that discharges the hydraulic mixture 2 and a moving unit 5 that moves the nozzle. The moving unit 5 is a robot arm or the like and can move the nozzle 4 vertically and horizontally. The moving unit 5 laminates the hydraulic mixture 2 discharged from the nozzle 4 from below to above. In the manufacturing method for a structural member according to the present embodiment, the nozzle 4 that discharges the hydraulic mixture is moved, and the hydraulic mixture 2 discharged from the nozzle 4 is laminated from below to above.

[0019] As shown in FIGS. 2 and 3, the opening shape of the nozzle opening 41 of the nozzle 4 is a trapezoid in which the upper base 411 is longer than the lower base 412. In the description of the opening shape of the nozzle opening 41, the direction in which the upper base 411 and the lower base 412 of the trapezoid extend is referred to as the width direction, and the direction in which the upper base 411 and the lower base 412 face each other is referred to as the height direction. The trapezoid of the opening shape of the nozzle opening 41 is longer in the width direction than in the height direction and is symmetric in the width direction. Both ends 411a and 411b of the upper base 411 are arranged outside the width direction of the ends 412a and 412b of the lower base 412, respectively.

[0020] The edge portion corresponding to the upper base 411 of the trapezoid at the edge of the opening of the nozzle opening 41 is denoted as the first edge portion 421. The edge portion corresponding to the lower base 412 of the trapezoid at the edge of the opening of the nozzle opening 41 is denoted as the second edge portion 422. The portions connecting the first edge portion 421 and the second edge portion 422 at the edge of the opening of the nozzle opening 41 (the portions corresponding to the hypotenuses of the trapezoid) are denoted as the third edge portion 423 and the fourth edge portion 424. The first edge portion 421 is longer than the second edge portion 422.

[0021] The nozzle 4 is preferably made of steel. The nozzle 4 may be made of plastic or carbon. The nozzle 4 may also be made of resin formed by resin 3D printing. The nozzle 4 only needs to have a material and strength that will not deform or break due to the pressure of the hydraulic mixture 2 discharged.

[0022] When the nozzle 4 moves horizontally by the drive of the moving part 5, the hydraulic mixture 2 discharged from the nozzle 4 is formed in a long-layered (sheet-like) shape. In the present embodiment, when the moving part 5 moves the nozzle 4 horizontally, it is possible to move the nozzle 4 not only in a straight line direction but also bent when viewed from above and below. The direction in which the nozzle 4 moves is referred to as the moving direction. The hydraulic mixture 2 discharged from the nozzle 4 is discharged onto a base (not shown) as the first layer, the second layer is discharged onto the first layer, and the third layer is discharged onto the second layer and laminated.

[0023] As shown in FIG. 1, the nozzle 4 is installed in a downward-opening direction. The nozzle 4 is installed in a direction in which the second edge portion 422 is located on the front side (advancing side) in the moving direction and the first edge portion 421 is located on the rear side in the moving direction. Thereby, the surface 21 that contacts the first edge portion 421 becomes the upper surface, and the surface 22 that contacts the second edge portion 422 becomes the lower surface, and the hydraulic mixture 2 discharged from the moving nozzle 4 is formed in a long-layered shape. As shown in FIG. 4, the vertical cross-sectional shape of the hydraulic mixture 2 discharged from the nozzle 4 is a trapezoid in which the upper base 23 corresponding to the shape of the nozzle opening 41 is longer than the lower base 24. That is, the width dimension of the lower side portion 262 of the layer 25 of the hydraulic mixture 2 discharged from the nozzle 4 is smaller than the width dimension of the upper side portion 261.

[0024] As shown in Fig. 5, when a new layer 252 of the hydraulic mixture 2 is laminated on the already formed layer 251 of the hydraulic mixture 2, as shown in Fig. 6, the lower layer 251 is crushed downward by the weight of the upper layer 252. At this time, the lower layer 251 before the upper layer 252 is laminated has a trapezoidal cross-sectional shape, and the width dimension of the lower part 262 is smaller than that of the upper part 261. For this reason, the lower layer 251 with the upper layer 252 laminated thereon is crushed so that the lower part 262 spreads in the width direction, and the lower part 262 and the upper part 261 have substantially the same width dimension. Thereby, the cross-sectional shape of the crushed lower layer 251 becomes substantially rectangular.

[0025] Furthermore, as shown in Fig. 7, when lamination is performed, the layer 25 having a trapezoidal cross-sectional shape is crushed by the weight of the upper layer 25, and the cross-sectional shape changes from trapezoidal to rectangular. Thereby, the upper part 261 of the lower layer 25 and the lower part 262 of the upper layer 25 have substantially the same width dimension, no unevenness is formed between the lower layer 25 and the upper layer 25, and the side surface of the structural member manufactured by laminating the hydraulic mixture 2 becomes smooth.

[0026] In the manufacturing apparatus and the manufacturing method of the structural member according to the present embodiment, in order to smooth the side surface of the laminated hydraulic mixture 2, there is no need to polish or install a temporary member for pressing the side surface to smooth the side surface when laminating. Thus, in the manufacturing apparatus and the manufacturing method of the structural member according to the present embodiment, the side surface of the structural member 3 manufactured by laminating the hydraulic mixture 2 can be smoothed without increasing the number of steps.

[0027] The adhesion strength between the layers of the laminated object such as the structural member 3 of the present embodiment becomes stronger as the adhesion area is wider. If the shape of the side surface of the laminated object is uneven, the adhesion area varies, and it becomes impossible to adhere with the original lamination width. In the present embodiment, since the cross-sectional shape of the layer 25 of the hydraulic mixture 2 becomes rectangular (square), it is expected to adhere over the entire lamination width and increase the adhesion area by maximizing the horizontal area where the upper surface 21 of the lower layer 25 and the lower surface 22 of the upper layer 25 overlap.

[0028] A structural member 3 manufactured using a cementitious material in a hydraulic mixture 2 is often used as an embedded formwork. Therefore, in the long term, the deeper the lamination marks, the more dirt such as rain and dust accumulates in the grooves, and stains such as those of dirty raindrops are likely to occur, further impairing the aesthetics. For this reason, by making the side surface of the structural member 3 used as an embedded formwork as flat as possible, it is expected that the accumulation of dirt and the like can be reduced and the long-term aesthetics can be maintained.

[0029] The structural member 3 may be used as an embedded formwork for placing concrete inside. In such a case, if the adhesion between the structural member 3 and the concrete placed inside is not sufficient, there is a risk of peeling of the formwork portion due to aging deterioration, shrinkage of the material, or external forces such as earthquakes. In such a case, as shown in FIG. 8, the angle θ1 of the hypotenuse (the fourth edge portion 424) corresponding to the inner surface on which the concrete is placed among the hypotenuses (the third edge portion 423 and the fourth edge portion 424) of the trapezoidal shape of the nozzle opening 41 of the nozzle 4 is made larger than the angle θ2 of the other hypotenuse (the third edge portion 423), and the shape of the nozzle opening 41 may be adjusted. Then, as shown in FIG. 9, the inner surface 35 (one side surface) of the structural member 3 (embedded formwork) on which the concrete is placed may not be made flat, but may be a surface with unevenness formed by leaving lamination marks or further raising it. The outer surface 36 on the side opposite to the inner surface 35 of the embedded formwork, that is, the surface (the other side surface) on which the concrete is not placed, may be a flat surface. As shown in FIG. 10, the concrete 6 may be allowed to penetrate into the unevenness of the inner surface 35 of the structural member 3 (embedded formwork) to increase the adhesion between the structural member 3 and the concrete 6. In the manufacturing apparatus 1 for a structural member according to the present embodiment, the side surfaces on one side and the other side of the structural member manufactured by laminating layers of a hydraulic structure can be made different in shape. For example, one side surface 35 can be made an uneven surface and the other side surface 36 can be made a flat surface.

[0030] Note that, when increasing the adhesion between the structural member 3 (embedded formwork) and the concrete, if the cross-sectional shape of the layer 25 of the hydraulic mixture 2 is in the shape of an umbrella where the width dimension of the upper portion 261 is smaller than the width dimension of the lower portion 262 when adhering to the concrete, air bubbles may accumulate in the gaps during concrete placement, and since the air bubbles are difficult to escape, there is a possibility that the filling will not be dense. On the other hand, if the cross-sectional shape of the layer 25 of the hydraulic mixture 2 is such that the width dimension of the upper portion 261 is larger than the width dimension of the lower portion 262, there are relatively few locations where air bubbles accumulate, and since the air bubbles are easily escaped during tamping with a vibrator, it is considered that the concrete is easily filled by its own weight. Since air bubbles do not accumulate, it is possible to increase the adhesion area between the structural member 3 and the concrete as a result. In the method for manufacturing a structural member according to the present embodiment, unevenness can be easily formed on the side surface of the structural member manufactured by laminating a hydraulic mixture.

[0031] The control of the side surface shape of the structural member 3 by the shape of the nozzle opening 41 of the nozzle 4 can be performed simply by changing the angle and shape of the trapezoid of the opening shape of the nozzle opening 41. If the structural member 3 (embedded formwork) is in a closed shape, one of the hypotenuses of the trapezoid of the opening shape of the nozzle opening 41 forms the inner surface 35 (one side surface) where the concrete is placed, and the other forms the exposed outer surface 36 (the other side surface). Thus, by adjusting the angle and shape of the nozzle opening 41, the outer surface 36 can be made to have a better appearance, and the inner surface 35 can be simultaneously and easily controlled to have a shape that provides good adhesion of the concrete.

[0032] A test was conducted in which the lamination of a hydraulic mixture (cement-based material) was performed by a manufacturing apparatus (additive manufacturing apparatus) for a structural member using the shape of the nozzle opening of the nozzle as a parameter, and the side surface shape was quantitatively evaluated. This test and the results will be described. The parameters are the shape of the nozzle opening and the distance (height dimension ΔZ) that the nozzle moves in the vertical direction when moving to the next layer (upper layer). The shape of the nozzle opening has five patterns.

[0033] (Overview) Similar to the above-described embodiment, the nozzle opening has a first edge (upper base) and a second edge (lower base). The second edge is disposed on the front side (advancing side) in the moving direction, and the first edge is disposed on the rear side in the moving direction. In the following description and drawings, the first edge may be referred to as the "upper base", the second edge may be referred to as the "lower base", and the distance between the first edge and the second edge may be referred to as the "height". In the shape of the nozzle opening, when the length dimension of the first edge is longer than the length dimension of the second edge, the shape is referred to as a "trapezoid", when the length dimension of the first edge is shorter than the length dimension of the second edge, the shape is referred to as an "inverted trapezoid", and when the length dimension of the first edge is the same as the length dimension of the second edge, the shape is referred to as a "rectangle".

[0034] As shown in the table of FIG. 12, the shapes of the nozzle openings of the five-pattern nozzles are designated as No. 1 to No. 5. The height dimension of the nozzle opening is 10.0 mm in all cases. For No. 1, the length dimension of the upper base is 37.5 mm and the length dimension of the lower base is 42.5 mm, and the case name is "inverted trapezoid 2.5". For No. 2, the length dimension of the upper base is 40.0 mm and the length dimension of the lower base is 40.0 mm, and the case name is "rectangle 0". For No. 3, the length dimension of the upper base is 42.5 mm and the length dimension of the lower base is 37.5 mm, and the case name is "trapezoid 2.5". For No. 4, the length dimension of the upper base is 45.0 mm and the length dimension of the lower base is 35 mm, and the case name is "trapezoid 5.0". For No. 5, the length dimension of the upper base is 47.5 mm and the length dimension of the lower base is 32.5 mm, and the case name is "trapezoid 7.5". The difference between the upper base and the lower base of the nozzle opening for each nozzle is 5 mm for the inverted trapezoid 2.5 and the trapezoid 2.5, 10 mm for the trapezoid 5.0, and 15 mm for the trapezoid 7.5. Tests were conducted for each of the five patterns from No. 1 to No. 5 when ΔZ was set to 7 mm and when it was set to 8 mm.

[0035] (Method for manufacturing the test body) As shown in Fig. 13, nozzles were attached to the additive manufacturing apparatus for each case, and the hydraulic mixture was laminated from bottom to top to fabricate a test piece having an oval cylindrical outer shape. The size of the test piece was width D = 150 mm, length L = 350 mm, height H = 300 mm, and radius R of the arc part = 75 mm. The test pieces were fabricated for both cases where ΔZ was 7 mm and 8 mm for each case.

[0036] (Measurement method) After the test piece hardened, the side shape of each test piece was measured five points at a time with a laser displacement meter. An image of the measurement method with the laser displacement meter is shown in Fig. 14. Fig. 15 and Fig. 16 show the measurement locations and measurement ranges. The five measurement locations are designated as Measurement No. 1 to Measurement No. 5.

[0037] (Evaluation method) Using the data obtained from the measurement with the laser displacement meter, the variance and arithmetic mean roughness (Ra) [Surface roughness JIS B 0601:2013] of the values were calculated, and the unevenness of the laminated evaluation surface was quantitatively evaluated. The calculation formula for the arithmetic mean roughness (Ra) is shown in Fig. 17.

[0038] (Test results) The test results when the distance (ΔZ) to the next layer is 7 mm are shown in Fig. 18, the graph of the variance is shown in Fig. 19, and the graph of the arithmetic mean roughness (Ra) is shown in Fig. 19. The test results when the distance (ΔZ) to the next layer is 8 mm are shown in Fig. 21, the graph of the variance is shown in Fig. 22, and the graph of the arithmetic mean roughness (Ra) is shown in Fig. 23. Side photos of each case when the distance (ΔZ) to the next layer is 7 mm are shown in Fig. 24. Side photos of each case when the distance (ΔZ) to the next layer is 8 mm are shown in Fig. 25. For reference, the graphs of the relationship between the laser displacement meter and the position in the height direction of the test piece when the distance (ΔZ) to the next layer is 7 mm are shown in Figs. 26 to 30 for each case, and the graphs of the relationship between the laser displacement meter and the position in the height direction of the test piece when the distance (ΔZ) to the next layer is 8 mm are shown in Figs. 31 to 35 for each case.

[0039] (Summary) From the above test results, when the nozzle openings are stacked in a rectangular shape, the hydraulically hardened mixture stacked in a rectangle has a vertical movement distance (ΔZ) of less than 10 mm when the nozzle moves to the next layer. In this case, the cross-section of the stacked material (layer) is deformed by the pressing between the upper part of the hydraulically hardened mixture of the previous layer and the nozzle opening, or by the pressing due to the self-weight of the laminate, and it was found that the cross-section becomes a trapezoidal shape with a small upper base and a large lower base. And when laminating with the shape of the nozzle opening (trapezoid) in the direction canceling the trapezoidal shape of the laminated cross-section diagram, it was found that the deformation due to pressing is canceled, the filament widths of the upper part of the previous layer and the lower part of the next layer become close, and the unevenness of the filament shape of the laminate is alleviated. From the results of this time, if the difference between the upper base and the lower base of the trapezoidal nozzle opening is 5 mm or more, an effect of reducing the unevenness on the surface (side surface) of the laminated body was recognized. Furthermore, it was recognized that the difference between the upper base and the lower base of the trapezoidal nozzle opening is preferably about 10 mm to 15 mm.

[0040] As described above, embodiments of the manufacturing apparatus for a structural member and the manufacturing method for a structural member according to the present invention have been described. However, the present invention is not limited to the above embodiments and can be appropriately changed without departing from the gist thereof. For example, in the above embodiment, the nozzle opening 41 of the nozzle 4 opens downward, but it may open laterally, obliquely downward, or the like.

[0041] The shape of the two layers 25 discharged from the nozzle 4 may be affected not only by the shape of the nozzle 4 but also by the hardness and thixotropy of the material (hydraulic mixture 2), the pressing degree of the nozzle 4, and the shape of the structural member 3. Therefore, it is desirable to design the shape of 41 of the nozzle 4 based on the case where the cross-sectional shape of the discharged hydraulic mixture 2 becomes rectangular. For this reason, when the cross-sectional shape of the discharged hydraulic mixture 2 is not limited to a trapezoid and is crushed in the vertical direction, it may be possible to replace it with the nozzle 4B as shown in FIG. 11. In the nozzle 4B, the opening shape of the nozzle opening 41B is such that the upper edge portion 431 and the lower edge portion 432 forming the upper surface and the lower surface are linear, and the side edge portions 433 and 434 forming the side surface are shaped to be recessed inward.

[0042] When using the structural member 3 as an embedded formwork, tile - pasting construction may be carried out on the outer surface 37 (the other surface) on the side where concrete is not placed. In such a case, as shown in FIG. 36, the angles θ of the two hypotenuses (the third edge portion 423 and the fourth edge portion 424) of the trapezoidal shape of the nozzle opening 41 of the nozzle 4 are increased. For example, when the trapezoid of the nozzle opening 41 has a symmetric shape in the width direction, the angle θ is set to a value such that the dimensional difference in the width direction between the first edge portion 421 corresponding to the upper base and the second edge portion 422 corresponding to the lower base of the trapezoid is 15 mm or more. The height dimension of the trapezoid of the nozzle opening 41 is, for example, 10 mm. Then, as shown in FIG. 37, the inner surface 35 (one side surface) where concrete is placed and the outer surface 37 (the other side surface) where concrete is not placed in the structural member 3 (embedded formwork) are made into surfaces with unevenness, leaving lamination marks or further raising them without being flat. As shown in FIG. 38, the concrete 6 is allowed to penetrate into the unevenness of the inner surface 35 of the structural member 3. By doing so, the adhesion between the structural member 3 and the concrete 6 can be improved. The joint material such as tile adhesive or driven - in concrete and other pasting materials 72 for pasting the tile 71 are allowed to penetrate into the unevenness of the outer surface 37 of the structural member 3. By doing so, the adhesion between the structural member 3 and the pasting material 72 can be improved. Instead of tile - pasting construction, plastering construction (stucco) may be carried out on the outer surface 37 of the above - mentioned structural member 3. Even in such a case, by allowing the mortar material to penetrate into the unevenness of the outer surface 37 of the structural member 3, the adhesion between the structural member 3 and the mortar material can be improved.

[0043] When using the structural member 3 as a plate-shaped exterior material or the like that is not in a closed shape, one side surface 35 of the structural member 3 may be formed as a concavo-convex surface, and the other side surface 36 may be formed as a flat surface. Also in such a case, as shown in FIG. 8, using a nozzle 4 in the shape of a trapezoid where the angles of the two hypotenuses (the third edge portion 423 and the fourth edge portion 424) of the nozzle opening 41 are different, as shown in FIG. 9, concavities and convexities are formed on one side surface 35 corresponding to the hypotenuse (the fourth edge portion 424) with a large inclination angle in the structural member 3, and the other side surface 36 corresponding to the hypotenuse (the third edge portion 423) with a small inclination angle is made flat. Then, as shown in FIG. 39, tile pasting construction may be performed on one side surface 35 of the structural member 3 where the concavities and convexities are formed. By allowing the pasting material 72 when pasting the tile 71 into the concavities and convexities of one side surface 35, the adhesion between the structural member 3 and the pasting material 72 can be improved. The flat other side surface 36 of the structural member 3 can enhance the aesthetic appearance. Instead of tile pasting construction, plastering construction (stucco) may be performed on one side surface 35 of the structural member 3 described above. Also in such a case, by allowing the mortar material to enter the concavities and convexities of one side surface 35 of the structural member 3, the adhesion between the structural member 3 and the mortar material can be improved.

[0044] When the side surface 126 corresponding to the hypotenuse of the trapezoidal cross-sectional shape of each layer 125 is an inclined surface that gradually faces outward in the width direction from the upper side to the lower side as in the conventional structural member 13 shown in FIG. 40, it is considered that the pasting material 72 for pasting tiles is displaced downward and difficult to construct. On the other hand, in the structural member 3 of the present embodiment, the side surface 26 corresponding to the hypotenuse of the trapezoidal cross-sectional shape of each layer 25 is an inclined surface that gradually faces inward in the width direction from the upper side to the lower side. And below the inclined surface, the upper surface 27 of the lower layer is arranged in a state of protruding outward in the width direction from the lower end position of the inclined surface. As a result, unevenness in which the upper surface 27 of the lower layer and the inclined surface of the side surface 26 of the upper layer are alternately arranged is formed on the side surface of the structural member 3. When filling the pasting material 72 of the concrete 6 or the tile 71 along the side surface of the structural member 3, the material that has entered the concave portion on the side surface of the structural member is in a state of being placed on the upper surface 27 of the lower layer that forms the concave portion, and is filled into the concave portion in a stable state. Further, even when the material filled in the concave portion protrudes from the concave portion, the material filled in the concave portion remains in the concave portion in a stable state, so that the structure is less likely to fall downward. As a result, the workability when filling the material along the side surface of the structural member 3 is good.

[0045] By adjusting the shape of the nozzle opening 41 of the nozzle 4, the side surface of the structural member 3 can be easily formed into an uneven surface or a flat surface. By forming unevenness on the side surface of the structural member 3, the adhesion area between the pasting material 72 of the concrete 6 or the tile 71 and the structural member 3 can be increased, so that the adhesion strength of the material can be improved. In this way, by changing the nozzle opening 41, the structural member 3 to which the pasting material 72 of the concrete 6 or the tile 71 adheres well can be manufactured.

[0046] In order to evaluate the adhesion strength between the structural member 3 and the concrete, a structural member 3 having a square tube shape was manufactured, and a test piece was prepared by driving concrete (compressive strength 29.1 N / mm 2 ) into it, and a test was conducted using a Japan Society for Civil Engineering adhesion tester. The width of each layer in which the square tube-shaped structural members 3 are laminated is 40 mm. Figure 41 shows the results of the adhesion tensile strength measured at four points. Figure 42 shows the fracture behavior. As shown in Figure 42, in all cases, the tensile fracture occurred not in the structural member 3 (the part denoted as the main material in Figure 42), but in the concrete part, and it was confirmed that the adhesion tensile strength at the interface between the structural member 3 and the concrete was higher than the tensile strength of the concrete.

[0047] There are 17 international goals adopted at the United Nations Summit in September 2015, namely the "Sustainable Development Goals (SDGs)". The manufacturing apparatus and manufacturing method of the structural member according to the present embodiment can contribute to the achievement of, for example, the goal of "9. Build the foundation for industry and technological innovation" among the 17 goals of the SDGs.

Explanation of Signs

[0048] 1 Manufacturing apparatus 2 Hydraulic mixture 3 Structural member 4 Nozzle 5 Moving part 21 Upper surface 22 Lower surface 41 Nozzle opening 421 First edge 422 Second edge 423 Third edge 424 Fourth edge

Claims

1. A nozzle for discharging a hydraulic mixture, and a moving part for moving the nozzle, and having a manufacturing apparatus for a structural member, the nozzle opening of the nozzle has a trapezoidal opening shape, and a first edge corresponding to the upper base of the trapezoid is set longer than a second edge corresponding to the lower base of the trapezoid, the moving part moves the nozzle such that a first surface formed by the hydraulic mixture discharged from the nozzle in contact with the first edge becomes the upper surface, and a second surface formed by the hydraulic mixture discharged from the nozzle in contact with the second edge becomes the lower surface, and the moving part moves the nozzle such that the hydraulic mixture discharged from the nozzle is laminated from the lower side to the upper side.

2. The nozzle opening opens downward, The moving part moves the nozzle such that the second edge of the nozzle opening is disposed in front of the first edge in the moving direction of the nozzle. The manufacturing apparatus for a structural member according to Claim 1.

3. Of the two hypotenuses of the trapezoid of the opening shape of the nozzle opening, a third edge corresponding to one hypotenuse and a fourth edge corresponding to the other hypotenuse each form an angle with the first edge that is different. The manufacturing apparatus for a structural member according to Claim 1 or 2.

4. Moving a nozzle for discharging a hydraulic mixture to laminate the hydraulic mixture discharged from the nozzle from the lower side to the upper side, the nozzle opening of the nozzle has a trapezoidal opening shape, and a first edge corresponding to the upper base of the trapezoid is set longer than a second edge corresponding to the lower base of the trapezoid, A manufacturing method for a structural member, wherein the nozzle is moved such that a first surface formed by the hydraulic mixture discharged from the nozzle in contact with the first edge becomes the upper surface, and a second surface formed by the hydraulic mixture discharged from the nozzle in contact with the second edge becomes the lower surface.

5. On the side surface of the structural member manufactured by laminating the layers of the hydraulic mixture formed by discharging from the nozzle opening from the lower side to the upper side, unevenness corresponding to the corner formed by the surface corresponding to the hypotenuse of the trapezoid of the opening shape of the nozzle opening and the first surface is formed. The manufacturing method for a structural member according to Claim 4.

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