JP4549157B2 - Seismic joint structure of concrete panels - Google Patents

Description

Detailed Description of the Invention

  The present invention relates to a seismic joint structure of a concrete panel (hereinafter referred to as a panel), and more specifically, heat insulation in which an inorganic fiber layer such as rock wool is formed on the outer surface of a panel attached to a wall surface of a building by a rocking construction method or the like. In the structure, the present invention relates to a seismic joint structure for a concrete panel in which a joint material is provided at a joint portion between adjacent panels to improve seismic safety.

  Generally, a building wall or the like needs to have certain fire resistance, heat insulation performance, and earthquake resistance based on the Building Standard Law. Moreover, in order to improve the habitability of a building, it is necessary to provide heat insulation, and various heat insulating materials are often used for walls, roofs, and the like.

  For example, lightweight cellular concrete (ALC) panels are highly heat-insulating and lightweight, and are therefore frequently used for detached houses, store-use houses, factories, outer walls of high-rise apartment houses, and the like. However, due to the recent high social needs for energy saving, other heat insulating materials are combined with ALC panels to further improve the heat insulating performance.

  In this case, a method of attaching urethane foam or the like has been used as a construction method in which a heat insulating layer can be formed on a wall without being uniformly interrupted regardless of the presence or absence of unevenness on the wall. However, urethane foam has problems such as environmental pollution due to the use of chlorofluorocarbons, difficulty in management at the construction site due to its extremely flammability, and risk of burning due to fire.

  As a method of solving these problems, a method of spraying sprayed rock wool, which has been conventionally used as a fireproof coating material, on a wall surface as a heat insulating material has come to be used. 4A and 4B show the cross-sectional structure. Moreover, FIG.4 (b) is an enlarged view of the joint part 43 vicinity of Fig.4 (a). That is, a plurality of ALC panels are arranged side by side, and both ALC panels 41a and 41b adjacent to each other are attached to the housing in a state where the joint portions 43 are fitted to each other, and on the outer surface of each ALC panel, The rock wool layer 45 is formed by the spraying method over the entire outer surface including the joint portion 43.

  In recent years, concrete panels such as ALC panels have adopted a rocking construction method that follows the deformation of the structural frame from the viewpoint of ensuring seismic safety. The rocking construction method is a mounting construction method in which each panel rotates slightly one by one with respect to the interlayer deformation of the structural frame due to an earthquake, wind pressure, or the like, and the joints between all the panels are displaced to follow the interlayer deformation.

  FIG. 5 shows a state in which the panel follows the interlayer deformation of the structural housing. That is, the panel 51 attached to the beams 54 and 55 which are structural frames due to an earthquake or the like causes the interlayer deformation l due to the horizontal stress A from the longitudinal direction of the beams 54 and 55. It shows a state in which the panel 51 follows the interlayer deformation of the structural frame by slightly rotating each time and shifting the joint portion 53 between adjacent panels.

  According to such a rocking construction method, conventionally used urethane foam follows the locking behavior of the panel by breaking from the vicinity of the joint. However, spray rock wool has higher tensile strength than foamed urethane, and does not break from the vicinity of the joint due to the locking behavior of the panel. That is, the rock wool sprayed on the panel surface hinders the locking behavior of the panel and impairs the seismic safety of the wall surface.

  Therefore, the present applicant forms an inorganic fiber layer such as rock wool on the outer surface of the panel, and there is no problem of environmental pollution such as foamed urethane, and the heat insulation structure of the panel is excellent in fireproof coating performance. In this case, it was considered that seismic safety could be provided by the fracture of the joint due to the rocking behavior.

  For example, Patent Document 1 proposes a structure in which tile expansion joints are provided at joints between wall panels. This will be described with reference to FIG. 6. A backup material 67 is fixed to the surface of a sealing material 65 placed on a joint 63 between a plurality of wall panels 61, and the backup material 67 protrudes from the panel surface. By making the finished height of the backup material 67 close to the finished surface of the adhesive layer 69 of the tile 60 bonded to the surface of the panel 61, it is easy to manage the installation of tiles on the wall panel surface.

  However, the expansion joint structure of the tiled finish as shown in this Patent Document 1 is intended to disperse the tensile stress of the adhesive layer 69 by providing a tile joint rather than ensuring seismic safety. There is a problem that the structure is provided, the structure is complicated, and the construction cost increases. Moreover, even if it tries to apply to the heat insulation structure which sprayed inorganic fiber materials, such as rock wool, to the panel, the construction is not easy, construction management is complicated, and there exists a problem that work efficiency falls.

JP 2003-206613 A

  The problem to be solved by the present invention is to provide a heat insulating structure in which an inorganic fiber layer such as non-polluting rock wool is provided on the outer surface of a concrete panel attached to a structural frame by a rocking construction method or the like. An object of the present invention is to provide a seismic joint structure for a concrete panel having excellent seismic resistance, in which the inorganic fiber layer breaks in the vicinity of the joint when rocking behavior occurs, and the structure can easily follow the interlayer deformation.

  In order to solve the above-mentioned problems, the seismic joint structure of a concrete panel according to the present invention has an inorganic fiber layer laminated on the outdoor side surface of a wall body constituted by arranging a plurality of concrete panels as described in claim 1. The gist of the heat insulating structure is that a formed joint material made of a heat insulating material is interposed in the joint portion of the peripheral portion of the concrete panel.

  In this case, it is preferable that the thickness from the top part of the molding joint material to the surface layer part of the inorganic fiber layer in the part of the molding joint material is 10 mm or less. More preferably, it is set to a range of 3 mm to 6 mm.

  Furthermore, the inorganic fiber layer is preferably formed by spraying rock wool onto the surface of the concrete panel.

  According to the seismic joint structure of a concrete panel according to claim 1 of the present invention, in a concrete panel attached to a structural frame by a rocking construction method or the like, a molded joint material is interposed in a joint portion between adjacent panels, An inorganic fiber layer is formed on the surface, and the tensile strength is lowered by making it thinner than the thickness of the inorganic fiber layer in other parts. As a result, rocking behavior occurs in the structural frame due to vibration such as an earthquake, and as a result, the inorganic fiber layer breaks at the thin joints, and the seismic safety of the concrete panel can be ensured.

  And by making the thickness from the top part of the molding joint material to the surface layer part of the inorganic fiber layer at the part of the molding joint material to be 10 mm or less, the fracture sensitivity to a relatively large earthquake or wind pressure is improved, and the earthquake resistance Safety is more certain.

  Moreover, when rock wool is sprayed on the concrete panel surface as an inorganic fiber layer, fire resistance, heat insulation, bending strength, etc. are improved even if the panel thickness is thin. Moreover, since urethane foam is not used, there is an advantage that environmental pollutants can be eliminated and damage caused by fires can be prevented.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. 1A and 1B are cross-sectional views of a joint structure of a concrete panel according to an embodiment of the present invention. In the concrete panel according to the present invention, the rock wool layer 13 is sprayed as an inorganic fiber heat insulating material on the surface of the lightweight cellular concrete (ALC) panels 11a and 11b to constitute a building as a wall having heat insulating properties.

  In this case, as long as the concrete panel is compatible with adhesion with spray rock wool, for example, calcium silicate molded board, wood wool cement board, pulp cement board, asbestos cement pearlite board, PC board, It is also possible to apply to a gypsum board, a slate board, an extrusion molding board, etc.

  The building has a plurality of ALC panels arranged side by side on the joint 15 between the two adjacent ALC panels 11a and 11b, along the joint 15 and to the ALC panel surface 19. After the molding joint material 17 is interposed with a certain thickness in the vertical direction, the rock wool is sprayed and completed on the ALC panel surface 19 and the molding joint material 17 surface. In addition, rock wool is generally used in which mineral fibers are mixed into cement.

  The molded joint material 17 is desirably made of a material having heat insulation performance such as polystyrene, polyurethane, polyethylene, or phenol foam so that the heat insulation performance of the joint portion 15 is not impaired.

  FIG. 2 is an enlarged cross-sectional view of the joint structure of the concrete panel shown in FIG. As shown in the figure, a plurality of ALC panels are arranged side by side, and the chamfered portions 24a and 24b of the joint portion 23 between the adjacent ALC panels 21a and 21b are matched to the cross-sectional shape of the chamfered portions 24a and 24b. Then, after the molded joint material 25 having a triangular bottom section and a tapered projection toward the surface layer is interposed, rock wool is sprayed on the ALC panel surface 27 and the molded joint material 25 surface to form the rock wool layer 29. Formed. By setting the average thickness (h) of the rock wool layer 29 at the site of the top portion 22 of the molding joint material 25 to 10 mm or less, the breaking strength of the rock wool layer 29 is lowered.

  In addition, the bonding strength of the bonding interface 27 between the ALC panels 21a and 21b and the rock wool layer 29, which are well-familiar with rock wool, is sufficiently high, but the molding joint material 25 having low material familiarity. The adhesive strength of the bonding interface 20 between the rock wool layer 29 and the rock wool layer 29 deposited on the surface thereof is low. For this reason, the bonding interface 20 with the rock wool layer 29 at the portion where the molding joint material 25 is located is structurally low.

  Therefore, when rocking behavior occurs in the ALC panels 21a and 21b due to an earthquake or the like, micro cracks are generated along the molding joint material 25 provided in the joint portion 23 of the ALC panels 21a and 21b, and rock wool Layer 29 breaks. As a result, the seismic safety of the ALC panels 21a and 21b is ensured. In addition, it is preferable that a release agent is applied to the bonding interface between the molding joint material 25 and the rock wool layer 29 because it is easy to follow the rocking behavior.

  Next, in the ALC panel (width 600 mm × length 2990 mm × thickness 100 mm) attached to the structural housing, a molding joint material was provided at the joint between adjacent ALC panels, and rock wool was sprayed. Thereafter, as shown in FIG. 5, an experiment was performed in which the structural frame was vibrated in three stages of a slight earthquake, a middle earthquake, and a strong earthquake in the in-plane direction, and the fracture condition of the rock wool layer and the rocking behavior of the ALC panel were confirmed. A slight earthquake has a panel deformation angle (radian) of 1/300, that is, an interlayer deformation of a 3 m panel is 10 mm, a middle earthquake has a panel deformation angle of 1/200, an interlayer deformation is 15 mm, and a strong earthquake is a panel Means that the deformation angle is 1/100 and the interlayer deformation l is 30 mm. This will be described in detail below.

(Examples 1-5)
First, in Examples 1 to 5 of the present invention, the average thickness (H) of the sprayed rock wool layer 29 on the ALC panel surface is 20 mm, and the thickness (h) of the rock wool layer 29 at the top portion 22 of the molding joint material 25 is set. ) Was 2, 4, 6, 8, 10 mm. Moreover, the molding joint material used was made of polystyrene, and as shown in FIG. 1 and FIG. 2, the lower part had a triangular section and a tapered shape toward the surface layer.

(Comparative Examples 1 and 2)
Comparative Examples 1 and 2 were tested for comparison with Examples 1 to 5, and the average thickness (H) of the sprayed rock wool layer 29 on the ALC panel surface was 20 mm. The thickness (h) of the rock wool layer 29 at the top 22 was 12, 14 mm. The same molding joint material as in Examples 1 to 5 was used.

(Comparative Example 3)
Comparative Example 3 was also an experiment conducted for comparison with Examples 1 to 5, in which the average thickness (H) of the sprayed rock wool layer 29 on the ALC panel surface was 20 mm, and no molding joint material was used.

  The results are shown in Table 1 below. In Table 1, the structural bodies of the above-mentioned examples and comparative examples were vibrated in three stages of in-plane direction of slight earthquake, middle earthquake, and strong earthquake, and as a result of visually observing the breaking situation of rock wool, etc. Or cracks that occurred due to the occurrence of microcracks along the joints (good circles), those that did not follow the chassis vibration and did not break at the joints, or cracks in the panel at the bracket mounting brackets The case where the fracture occurred was defective (x mark), the vibration of the casing was followed to some extent, and the fracture of the joint part which was not perfect was judged as slightly good (Δ mark). In the comprehensive evaluation, the traceability is particularly good in slight earthquakes, and in the middle and strong earthquakes, breaks occur along the joints and the characteristics are extremely good, and are marked as ◎.

  As is clear from the results of Table 1, according to the seismic joint structure of the present invention (Examples 1 to 5), when a strong earthquake was given to the frame, in Example 1, some cracks were confirmed by the slight earthquake. However, in Examples 2 to 5, the thickness of the rock wool of the molded joint material part follows the vibration of the casing, the joint part does not break, a slight earthquake, some wind power, etc. It was confirmed that the rock wool layer at the joints followed the vibration of the frame without breaking the joints, and seismic safety was ensured.

  Also, according to the product of the present invention, when a middle or strong earthquake is applied to the frame, Examples 1 to 3 are completely broken at the joint in the case of the middle earthquake, and Examples 4 and 5 are joints. Although some cracks were observed in the entire area, some of the inorganic fibers were bound, but in any case where the rock wool thickness of the molded joint material part was small, microcracks occurred over the entire joint area. It was confirmed that the rock wool layer was broken and seismic safety was ensured. And in the case of the product of the present invention, in particular, in the range of 3 to 6 mm in the thickness of the rock wool layer at the top of the molded joint material, the rock wool layer at the joint does not break against a slight earthquake or some wind force. In addition, following the vibration of the frame, it was also confirmed that the frame breaks at the joints without obstructing the rocking behavior of the panel in the event of strong earthquakes or strong frame vibrations such as large typhoons. Therefore, in Examples 2 and 3, it was determined as ◎ as an overall evaluation.

  On the other hand, according to the comparative product (Comparative Examples 1 to 3), in Comparative Example 3 in which the molded joint material is not interposed, the followability to the vibration of the frame is poor with respect to the slight earthquake, and it is attached in the middle or strong earthquake. Only cracks and breaks in the panel were seen at the metal part, and no breaks at the joints were observed. On the other hand, in Comparative Examples 1 and 2, the followability to the body vibration is not so good with respect to the slight earthquake, but there is a break at the joint part even for the middle earthquake or strong earthquake, Cracks and fractures were observed, and the evaluation was slightly inferior to the product of the present invention.

  Therefore, from these results, like the seismic joint structure of the present invention, the rock wool layer was formed by spraying on the surface of the ALC panel, and when the molding joint material was interposed in the joint part between the ALC panels, The rock wool layer at the joint portion is broken by a vibration such as an earthquake, and each ALC panel can show a rocking behavior. In addition, by setting the thickness from the top of the molding joint to the surface layer of the rock wool layer at 10 mm or less at the site of the molding joint, the breaking characteristics of rock wool can be further improved, and the seismic safety can be improved. It became clear.

  In addition, from the above results, the rock wool layer does not break during minor earthquakes or slight earthquakes such as wind power, and follows the vibration of the frame, and follows the rocking behavior of the panel during strong earthquakes or strong earthquakes such as large typhoons. And in order to fracture | rupture a joint part, it turned out that the thickness of the rock wool layer of the top part of a shaping | molding joint material has preferable 3 mm-6 mm.

  In addition, as a form of the said molding joint material, the thing except having shown by FIG. 1 and FIG. 2 is also considered. For example, as shown in FIG. 3, the cross-sectional shape may be circular, semicircular, square, trapezoidal, or triangular, and when the structural frame vibrates, it can be concentrated on the line along the joints of the panel. Any form can be used. If the rock wool layer thickness (h) at the top of these various types of molded joint materials is 10 mm or less, the same results as those shown in Table 1 can be obtained.

  Although various embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention. For example, in the said Example, although the example of rock wool was shown as an inorganic fiber layer on the surface of a concrete panel, it can apply also to what used fiber materials, such as glass wool. In addition, the size of the ALC panel is not limited to the above-mentioned example product, and it is needless to say that the spraying amount of the rock wool layer on the panel surface is not limited to the above example.

It is sectional drawing which showed the joint structure of the concrete panel which concerns on one Embodiment of this invention. It is the figure which expanded and showed the joint structure of the concrete panel shown by FIG. It is the figure which showed other embodiment of the molding joint material applied to this invention. It is sectional drawing of the rock wool surface layer concrete panel generally known conventionally. It is explanatory drawing of the rocking behavior of the ALC panel generally known conventionally. It is the figure which showed the tile expansion joint structure of the tiled concrete panel as a prior art example.

Explanation of symbols

11a, 11b ALC panel 13 Rock wool layer 15 Joint part 17 Molded joint material 21a, 21b ALC panel 23 Joint part 25 Molded joint material 29 Rock wool layer 54, 55 Beam A Horizontal stress l Interlayer deformation

Claims (3)

  In a heat insulating structure in which an inorganic fiber layer is laminated on the outdoor side surface of a wall body composed of a plurality of concrete panels arranged side by side, a molding joint material made of a heat insulating material is interposed in the joint portion of the peripheral edge of the concrete panel Seismic joint structure of concrete panels characterized by   The seismic joint structure for a concrete panel according to claim 1, wherein a thickness from the top part of the molding joint material to the surface layer part of the inorganic fiber layer in the part of the molding joint material is 10 mm or less.   The seismic joint structure according to claim 1 or 2, wherein the inorganic fiber layer is formed by spraying rock wool onto the surface of the concrete panel.

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