JP3623871B2 - Seal member for precast structure - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a seal member that seals between a sleeve joint and a reinforcing bar when a precast structure is manufactured by placing concrete with one end of a deformed reinforcing bar inserted into the sleeve joint.
[0002]
[Prior art]
A precast structure used for a column or the like is manufactured by placing concrete in a state in which one end portions of a plurality of deformed reinforcing bars parallel to each other are inserted into a plurality of sleeve joints, respectively. In this precast structure, the internal space of the sleeve joint is open at one end face, and the reinforcing bar protrudes from the other end face. When connecting the precast structures, insert the end of the reinforcing bar protruding from the other precast structure into the sleeve joint of one precast structure, and grout such as mortar or cement milk into the internal space of the sleeve joint. Fill with material and cure.
[0003]
By the way, when placing concrete for manufacturing the precast structure, a seal member is used between the sleeve joint and the reinforcing bar so that cement milk, which is a component of the concrete, does not enter the internal space of the sleeve joint. Need to seal.
In Japanese Patent Application Laid-Open No. 63-7453, an elastic sealing member made of expanded polystyrene having an annular shape is mounted in an annular receiving groove at one end of a sleeve joint. In this mounted state, the end of the reinforcing bar is press-fitted into the seal member so as to face the internal space of the sleeve joint. In this way, the inner peripheral surface of the seal member is brought into close contact with the outer peripheral surface of the reinforcing bar with elasticity, thereby preventing cement milk or the like from entering the internal space of the sleeve body.
[0004]
[Problems to be solved by the invention]
However, in the above-mentioned sleeve joint, it was not possible to reliably prevent the entry of cement milk or the like with the seal member when placing concrete. The reason is that the rib of the deformed reinforcing bar elastically deforms the seal member over a relatively large region, and a gap having a size that cannot be ignored is generated between the two. In particular, when there is a vertical rib extending along the axis of the reinforcing bar, this gap is also formed along the vertical rib, and the sealing performance is impaired.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problem, the seal member for a precast structure according to the invention of claim 1 has a portion that fits into an annular receiving groove formed at one end of the sleeve joint, and is provided at one end of the sleeve joint. An annular main body portion to be mounted, and a plurality of annular flange portions formed on the inner periphery of the main body portion and in contact with the outer periphery of the reinforcing bar, the end surface of the main body portion facing the back side of the sleeve joint, An annular groove is formed on the end surface of the portion that fits into the annular housing groove to divide the portion that fits into the annular housing groove into an outer portion and an inner portion.
According to a second aspect of the present invention, in the precast structural seal member according to the first aspect, the outer peripheral surface of the portion that fits into the annular receiving groove has a taper that increases in diameter toward the back of the sleeve joint. An annular groove is also formed on the outer peripheral surface.
According to a third aspect of the present invention, in the precast structural seal member according to the first aspect, an annular convex portion is formed on the outer peripheral surface of the portion that fits into the annular receiving groove .
[0006]
【Example】
An embodiment of the present invention will be described below with reference to FIGS. FIG. 2 shows a state immediately after the production of the column precast structure A is completed. The production of the precast structure A will be schematically described. First, a reinforcing bar rod 10 is formed by bundling an annular shear reinforcement bar 12 at intervals with a plurality of main bars 11 (deformed bar bars) extending in parallel with each other. Next, the reinforcing bar rod 10 is accommodated in the mold 30, and one end portion of the sleeve joint 20 is connected to one end portion of the main reinforcing bar 11. At this time, the other end of the sleeve joint 20 is brought into contact with the inner surface of one end wall 31 of the mold 30 via packing or the like and supported by a support tool (not shown). The other end (not shown) of the main bar 11 penetrates the other end wall of the mold 30 and protrudes to the outside. Further, one end of two polyvinyl chloride pipes 41 and 42 is connected to each sleeve joint 20, and the other end is closed with a stopper and supported on the peripheral wall 32 of the mold 30. In this state, by casting concrete C, a precast structure A is manufactured.
[0007]
The precast structure A manufactured as described above is used for a column in a state where the sleeve joint 20 is erected, for example. In the sleeve joint 20 of the upper floor precast structure A, the upper end portion of the main bar 11 extending upward from the lower floor precast structure A is accommodated, and in this state, grout material is injected from one pipe 41, Both the precast structures A are connected by filling the inner space of the sleeve joint 20 with the grout material while removing air from the pipe 42.
[0008]
As shown in FIG. 3, the main reinforcing bar 11 has a pair of vertical ribs 11a extending in the axial direction on the outer peripheral surface having a circular cross section, and a horizontal rib 11b extending to the vertical direction and extending approximately 180 ° in the circumferential direction. doing.
On the other hand, the sleeve joint 20 has a cylindrical shape, and joint portions 24 and 25 connecting the pipes 41 and 42 are formed on the peripheral walls at both ends. An annular housing groove 21 is formed at one end of the sleeve joint 20. The housing groove 21 is formed by a pair of annular flanges 21 a and 21 b that project radially and inward from the inner peripheral surface of the sleeve joint 20. In addition, the inner diameter of the flange 21b on the back side is smaller than that of the flange 21a on the main bar insertion end side.
[0009]
An annular seal member 50 made of rubber (elastic material) is attached to one end of the sleeve 20. The detailed structure of the seal member 50 is omitted in FIG. 3 and will be described with reference to FIG. The seal member 50 includes a main body 51 including a large diameter portion 51a and a small diameter portion 51b. The large-diameter portion 51a of the main body 51 is fitted into the receiving groove 21, and the small-diameter portion 51b is fitted inside the flange 21a.
[0010]
The outer peripheral surface 51x of the large-diameter portion 51a of the main body 51 is tapered so as to expand toward the back side of the sleeve joint 20, and an annular groove 51y having a semicircular cross section is formed at the axially intermediate portion of the outer peripheral surface 51x. Is formed. Further, an annular groove 51z having a complete annular shape is formed on one end face of the large diameter portion 51a, that is, the end face on the back side of the sleeve joint 20, and the large diameter portion 51a is divided into the outer portion 50A and the inner portion 50B. It is divided into. The annular groove 51z becomes wider as it goes to the back of the sleeve joint 20.
[0011]
In the natural state (not elastically deformed) before being accommodated in the sleeve joint 20, the outer diameter of the rear end portion of the large diameter portion 51 a is larger than the inner diameter of the accommodation groove 21 of the sleeve joint 20, and the large diameter portion 51 a The outer diameter of the end portion on the opening end side (that is, the end portion close to the small diameter portion 51 b) is smaller than the inner diameter of the accommodation groove 21. Moreover, the outer diameter of the small diameter part 51b is formed slightly larger than the inner diameter of the flange 21a.
[0012]
A plurality (three in this embodiment) of ring-shaped flanges 53 that are coaxial with each other are formed on the inner peripheral surface 51s of the cylindrical surface of the main body 51 of the seal member 50. These flanges 53 are separated from each other in the axial direction of the main body 51 at equal intervals. These flange portions 53 have the same shape and the same inner diameter, and protrude from the inner peripheral surface 51s of the main body portion 51 in the radial direction and the inner direction by the same height.
As shown in FIGS. 1A and 1B, the inner diameter Da of the flange portion 53 of the sealing member 50 is smaller than the diameter Dx of the outer peripheral surface of the main reinforcement 11 where the ribs 11a and 11b are not formed. Further, the inner diameter Db of the main body 51 of the seal member 50 is larger than the diameter Dy of the circumscribed circle of the ribs 11a and 11b.
[0013]
As best shown in FIG. 1A, the cross-sectional shape of the flange portion 53 is the same along the circumferential direction, the proximal end portion on the radially outer side is thick, and the distal end portion on the radially inner side is thin. Yes.
[0014]
The effect | action in the manufacturing process of the said precast structure A of the sealing member 50 which makes the said structure is demonstrated. First, as shown in FIG. 1A, the seal member 50 is mounted in the accommodation groove 21 of the sleeve joint 20. At this time, since the annular groove 51z is formed on the end surface of the main body 51 and the annular groove 51y is formed on the outer peripheral surface 51x, the outer portion 50A can be easily deformed inward, and the housing groove of the seal member 50 Easier to install on 21. Further, since the outer peripheral surface 51x of the large-diameter portion 51a is tapered and the outer diameter of the inner portion of the sleeve joint 20 is larger than the inner diameter of the receiving groove 21, only this portion is formed on the inner peripheral surface of the receiving groove 21. Or this part touches more strongly than other parts. Therefore, the sealing performance between the sleeve joint 20 and the seal member 50 is enhanced by this strong contact.
[0015]
Next, as shown in FIGS. 1B and 3, the end portion of the main bar 11 is inserted through the seal member 50 and partway into the internal space of the sleeve joint 20. When inserting the main bar 11, the diameter Db of the inner peripheral surface 51 s of the main body 51 of the seal member 50 is larger than the diameter Dy of the circumscribed circle of the rib 11 a of the main bar 11, so that the insertion resistance is substantially generated only at the flange 53. However, the main body 51 does not serve as an insertion resistance. As a result, the insertion resistance can be reduced.
[0016]
Further, when the main bar 11 is inserted, even if the main bar 11 is inserted in a state shifted from the axial center of the sleeve joint 20, the inner portion 50B is formed because the annular groove 51z is formed in the back end surface of the main body 51. Is deformed. Also from this point, the insertion resistance of the main muscle 11 can be reduced.
[0017]
In the state where the main bar 11 is inserted into the seal member 50, the inner diameter Da of the flange 53 of the seal member 50 is smaller than the diameter Dx of the outer peripheral surface of the main bar 11 where the ribs 11a and 11b are not formed. It can contact the outer peripheral surface of the main bar 11 with elasticity, and can reliably contact even if the sleeve joint 20 and the axis of the main bar 11 are slightly shifted. Furthermore, even if the main reinforcing bars 11 have different diameters, they can be reliably in contact with each other as long as the diameter is within a predetermined range.
[0018]
Even if there is a variation in the inner diameter of the receiving groove 21 of the sleeve joint 20 made of a casting, this variation can be almost absorbed by the outer portion 50A of the annular groove 51z being displaced inward. As a result, it is possible to reduce the change that this variation gives to the contact state of the collar portion 53 to the outer periphery of the main muscle 11 and to secure the expected contact state.
[0019]
As described above, since the collar portion 53 is in a good contact state with the sleeve joint 20 and the main reinforcing bar 11, the cement milk enters the internal space of the sleeve joint 20 when the concrete C is placed as described above. Can be surely stopped.
[0020]
Next, other embodiments of the present invention will be sequentially described. In these embodiments, components corresponding to the preceding embodiments are given the same reference numerals in the drawings, and detailed descriptions thereof are omitted.
In the embodiment of FIG. 4, an O-ring 55 is fitted in an annular groove 53y formed in the outer peripheral surface 53x of the seal member 50, and protrudes from the outer peripheral surface 53x, thereby forming an annular convex portion. In this embodiment, in a state where the seal member 50 is housed in the housing groove 21 of the sleeve joint 20, only the O-ring 55 is in contact with the inner peripheral surface of the housing groove 20, so that the contact pressure between them can be increased. Can be improved. Instead of the O-ring 55, an annular convex portion that is integrated with the seal member 50 may be used.
[0021]
In the embodiment of FIG. 4, the inner diameter of the flange 21 b is larger than that of the first embodiment, and the annular groove 53 z formed on the end surface of the seal member 50 is continuous with the internal space of the sleeve joint 20. Therefore, when the grout is filled into the internal space of the sleeve joint 20 in order to connect the precast structures, the grout enters the annular groove 53z and solidifies there, so that the strength of the seal member 50 is increased. Can do.
[0022]
In the embodiment of FIG. 5, the inner peripheral surface 51 s of the main body 51 of the seal member 50 is tapered such that the diameter decreases toward the back of the sleeve joint 20. The three flange portions 53 ′, 53 ″, 53 ′ ″ have different shapes but have the same inner diameter.
In this embodiment, when the deformed reinforcing bars are inserted, the flanges 53 ′, 53 ″, 53 ′ ″ are elastically deformed into different shapes. Therefore, even if the diameter of the deformed reinforcing bar changes, one of the buttocks can secure the best contact state, and as a result, the sealing performance can be improved. Moreover, in the said Example, since the internal peripheral surface 51s of the main-body part 51 makes a taper, and can play the role which guides the main reinforcement 11, insertion of the main reinforcement 11 is made easy.
[0023]
In the embodiment of FIGS. 6 and 7, a continuous spiral ridge 152 is formed on the inner peripheral surface 51 s forming the cylindrical surface of the main body 51. A round portion of the collar 152 becomes an annular collar 153. The cross-sectional shape of the flange 153 is the same as that in the above-described embodiment. In the spiral groove 154 formed between the flange portions 153, a large number of partition walls 155 extending in the radial direction and the inward direction from the main body portion are formed at an angular interval of 180 °. The partition wall 155 connects the flanges 153 adjacent in the axial direction. Intrusion of cement milk is prohibited by the spiral-shaped ridge 152 coming into contact with the outer periphery of the main muscle. Cement milk passing through the spiral groove 154 is prohibited from entering by the large number of partition walls 155.
[0024]
The present invention is not limited to the above embodiments, and various modes are possible. For example, the precast structure may be for walls or beams. As a material for the seal member, foamed polystyrene, urethane, or the like may be used in addition to rubber. The rib of the deformed reinforcing bar may be a threaded rib.
In addition, the annular groove 51z formed in the main body 51 of the seal member 50 is a continuous complete ring in the above-described embodiment, but at a predetermined angular interval between the outer portion 50A and the inner portion 50B. A bridging portion may be formed, and the annular groove 51z may be divided into a plurality of arc grooves. In this case, the bridging portion needs to be small so that one of the outer portion 50A and the inner portion 50B is not significantly affected by the other elastic deformation.
Further, the annular groove may have an equal width along the axial direction. The thickness of the collar portion may be constant along the radial direction of the seal member. The main body of the seal member may be attached to one end of the sleeve joint by screwing.
[0025]
【The invention's effect】
As described above, according to the first aspect of the present invention, since the sealing member has a plurality of flanges, the sealing member elastically contacts the outer peripheral surface of the reinforcing bar even though the insertion resistance of the reinforcing bar is small. Therefore, a good seal can be provided between the reinforcing bar and the sleeve joint. Moreover, even when the axis | shaft of a reinforcing bar and a sealing member has shifted | deviated, or when the deformed reinforcing bar from which a diameter differs is used, the contact state to the reinforcing bar outer peripheral surface of a collar part is securable. In addition, according to the first aspect of the present invention, the annular groove is formed on the back end surface of the main body, so that the portions located on the outer side and the inner side of the annular groove are easily elastically deformed, and one elastic deformation is caused. The influence on the other can be reduced. As a result, for example, the following effects can be obtained.
(I) Even if the inner diameter of the end portion of the sleeve joint varies, it can be absorbed by the deformation of the outer portion of the seal member, and the change of the contact state of the collar portion with the outer periphery of the reinforcing bar can be suppressed.
(Ii) Even when the reinforcing bar is inserted in a state shifted from the axis of the sleeve joint, the insertion resistance of the reinforcing bar can be reduced by deformation of the inner part.
[0026]
According to the invention of claim 2, since a part of the outer peripheral surface of the main body part receives the elastic force of the main body part intensively and comes into contact with the inner peripheral surface of the receiving groove, the seal between the sleeve joint and the seal member Can be improved. Moreover, since the elastic deformation of the outer part of the main body portion is further facilitated by the annular grooves formed on the end surface and the outer peripheral surface of the main body portion, the seal member can be easily fitted into the housing groove of the sleeve joint. .
According to the invention of claim 3, the annular convex portion formed on the outer peripheral surface of the main body portion receives the elastic force of the main body portion intensively and contacts the inner peripheral surface of the housing groove of the sleeve joint. The sealing property between the sealing members can be improved.
[Brief description of the drawings]
FIG. 1A is an enlarged cross-sectional view showing a part of a sleeve joint in a state where a seal member according to the present invention is mounted, and FIG. 1B is an enlarged cross-sectional view showing a state where a reinforcing bar is inserted into the sleeve joint. It is.
FIG. 2 is a cross-sectional view showing a state immediately after completion of manufacturing a precast structure.
FIG. 3 is a cross-sectional view of the entire sleeve joint showing a state where a seal member is mounted and a reinforcing bar is inserted.
FIG. 4 is a view corresponding to FIG. 1 (A) showing another embodiment of the seal member of the present invention.
FIG. 5 is a cross-sectional view showing still another embodiment of the seal member of the present invention.
FIG. 6 is a view corresponding to FIG. 1 (A) showing still another aspect of the seal member of the present invention.
7 is a front view of the seal member as viewed from the direction of arrow VII in FIG. 6. FIG.
[Explanation of symbols]
11 ... Main bar (deformed bar)
11a, 11b ... rib 20 ... sleeve joint 21 ... receiving groove 50 ... sealing member 50A outer part 50B inner part 51 ... main part 51s ... main part inner peripheral surface 51x ... main part outer peripheral surface 51z ... annular groove 53, 53 ' , 53 ″, 53 ′ ″, 153… buttocks C… concrete

Claims (3)

An elastic seal that is attached to one end of a sleeve joint and seals between the sleeve joint and the reinforcing bar when manufacturing a precast structure by placing concrete with one end of the deformed reinforcing bar inserted into the sleeve joint The member has a portion that fits into an annular receiving groove formed at one end portion of the sleeve joint, and is formed on the inner periphery of the main body portion. A plurality of annular flanges in contact with the outer periphery of the reinforcing bar, and fitted into the annular housing groove on the end surface of the body portion facing the back side of the sleeve joint and fitted into the annular housing groove. A sealing member for a precast structure, wherein an annular groove is formed to divide a portion into which the portion is stuck into an outer portion and an inner portion. The outer peripheral surface of the portion that fits into the annular receiving groove has a taper that increases in diameter toward the back of the sleeve joint, and an annular groove is also formed on the outer peripheral surface. Item 2. The precast structural seal member according to Item 1. The seal member for a precast structure according to claim 1, wherein an annular convex portion is formed on an outer peripheral surface of a portion that fits into the annular housing groove .

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