JP4355694B2 - Precast material - Google Patents

Description

  The present invention relates to a precast member made of reinforced concrete that constitutes a column, a wall, and the like, and particularly relates to an improvement in a joint structure provided at a lower end portion thereof.

  Patent Document 1 discloses a structure for joining a precast column (precast member) to a lower component of a building. This joint structure includes a plurality of cylindrical joints embedded perpendicularly to the lower end portion of concrete. The lower end (open end) of the joint is open to the lower surface side of the concrete. In the upper part of the internal space of the joint, the lower end of the reinforcing bar of the precast column is inserted.

  The precast column further includes a plurality of exhaust passages and one injection passage. The inner end of the exhaust passage is connected to the upper end portion of the inner space of the joint, and the outer end is opened on the outer peripheral surface of the concrete. Further, the inner end of the injection path is connected to the lower end portion of the inner space of the selected joint, and the outer end thereof opens to the outer peripheral surface of the concrete. These exhaust passages and injection passages are horizontal.

  When joining the precast column to the lower component of the building, suspend the precast column and position it above the lower component, and from the lower component to the lower part of the internal space of the joint of the precast column The upper end portion of the reinforcing bar protruding upward is inserted, and a gap serving as a joint space is formed between the lower surface of the precast column and the upper surface of the lower component portion. In this state, mortar (filler) is injected from the injection path. As a result, the mortar fills the joint space through the joint to which the injection path is connected, further fills the internal space of all the joints, and further reaches the outer end through the exhaust path. In the mortar filling process, air in the joint space and the internal space of the joint is discharged from the exhaust passage.

As described above, the precast column is joined to the lower component. The lower end part of the reinforcing bar of the precast column and the upper end part of the reinforcing bar of the lower component part are connected via a joint and a mortar filled in the joint.
JP-A-9-177249

  In the precast column of Patent Document 1, since the exhaust passage is horizontal, the mortar can reach the outer end of the exhaust passage with air remaining on the upper end of the internal space of the joint and the upper side of the exhaust passage. There was sex. The connection strength between the reinforcing bars in Patent Document 1 is sufficient in terms of standards, but when the connection strength is further improved, residual air at the upper end of the internal space of the joint becomes an obstacle. Similarly, the concrete strength is sufficient in terms of standards, but when the concrete strength is further improved, the residual air in the exhaust passage becomes an obstacle.

  In order to solve the above-mentioned problems, a precast member of the present invention has (a) concrete and (b) an internal space, embedded perpendicularly to the lower end of the concrete, and the open end of the internal space is made of concrete. A plurality of tubular joints open to the lower surface side, and (c) embedded in the concrete and extending vertically, and the lower end part enters the upper part of the inner space of the joint or is screwed into the upper end part of the joint A plurality of reinforcing bars; and (d) a plurality of exhaust passages formed in the concrete, the inner ends of which are connected to the upper ends of the internal spaces of the joints, and the outer ends that open to the outer peripheral surface of the concrete. In the precast member joined to the lower component part by inserting a plurality of reinforcing bars protruding upward from the lower component part into the internal space, the precast member joined to the lower component part, among the plurality of exhaust passages Part of the exhaust passage without any, has a slope which forms an upwardly towards the outer end, and wherein the outer end of the exhaust passage is higher than the inner end.

  According to the above configuration, since the exhaust passage has an upward gradient, when the filler is filled into the internal space of the joint, the internal space of the joint can be well vented to reliably fill the filler. Can do. As a result, the connection strength between the reinforcing bars can be further increased. In addition, air can be well vented in the exhaust passage, and the filler can be reliably filled in the exhaust passage, so that the strength of the concrete can be further increased.

Preferably, the plurality of reinforcing bars have a plurality of main bars arranged along the outer peripheral surface of the concrete and a plurality of core bars arranged inside the main bars, and the core bars are inserted or screwed together. The exhaust passage connected to the joint has the above gradient. According to this, although the exhaust passage connected to the joint into which the core bars are inserted or screwed is long, the air can be vented satisfactorily.
Preferably, all of the exhaust passages have an upward slope. Thereby, the connection strength of the reinforcing bars in all the joints can be improved, and the concrete strength can be increased to the maximum.
Preferably, the exhaust passage has an upward gradient substantially over the entire length. Thereby, the air bleeding effect can be exhibited to the maximum extent. In this case, if the exhaust path is formed by a single straight pipe inclined, the configuration can be simplified.

Preferably, the joint is formed with a connecting port portion having a central axis that is horizontal and continuous with an upper end portion of the internal space, and the pipe that forms the exhaust passage includes a short first portion that extends horizontally from the inner end thereof. And a second portion formed longer than the first portion and extending upwardly toward the outer end, and the inner end of the tube is inserted and connected to the connecting port portion. According to this, the connection of the 1st part of the pipe | tube to the connection port part of a joint can be performed reliably, and the advantage of an upward gradient can be enjoyed.
Preferably, the first and second portions of the pipe forming the exhaust passage are made of separate straight pipes, and the straight pipes of the first and second portions are connected by elbow pipes. According to this, by using an elbow pipe, bending of the pipe becomes unnecessary.

Preferably, the concrete further includes a plurality of lower passages positioned below the exhaust passage, the inner ends of the lower passages being connected to the internal spaces of the joints, and the outer ends of the concrete. Open to the outer peripheral surface of the concrete, and at least some of the plurality of lower passages have a slope that faces upward toward the outer end, and the outer end of the lower passage is higher than the inner end. . For example, one of the plurality of lower passages may be provided as a filling material injection passage and the other may be provided as an exhaust passage. At this time, air can be favorably removed by giving a gradient to the lower passage serving as the exhaust passage.
Preferably, the lower passage has substantially the same structure as an exhaust passage connected to a common joint. Thereby, the benefits associated with the structure of the exhaust passage can be enjoyed.

  According to the present invention, air bleeding can be performed satisfactorily, so that the connection strength between the reinforcing bars can be further increased and the strength of the concrete can be further increased.

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, a precast column 10 (a precast member made of reinforced concrete) includes a concrete 11 having a square cross section and a number of reinforcing bars embedded in the concrete 11 as a basic structure.

  The precast column 10 of the present embodiment includes, as reinforcing bars, a plurality of, for example, 12 vertical main bars 12 arranged along the outer peripheral surface of the concrete 11, and a plurality of, for example, four vertical core bars arranged on the inner side thereof. 13. Further, an annular shear reinforcement bar (not shown) is wound around the main bar 12 at intervals.

  The precast column 10 further includes the same number of joints 14 as the total number of the main bars 12 and the core bars 13. These joints 14 are embedded in the lower end portion of the concrete 11 in a vertical cylinder shape. The lower end (open end) of the joint 14 is open to the lower surface side of the concrete 11.

  In the upper part of the internal space 14 a of the joint 14, the lower end of the corresponding main reinforcement 12 or core reinforcement 13 enters. An annular seal member 15 made of rubber is fitted into the upper end portion of the joint 14. The seal member 15 is used to prevent cement from entering between the upper end portion of the joint 14 and the main reinforcement 12 or the core reinforcement 13 when the precast column 10 is manufactured.

  As shown in FIGS. 4 and 5, short cylindrical connection ports 14 x and 14 y projecting in the radial direction are formed at the upper and lower ends of the joint 14, respectively. The central axes of these connection ports 14x and 14y are horizontal and orthogonal to the central axis of the joint 14. The connection port portion 14 x is continuous with the upper end portion of the internal space 14 a of the joint 14. The connection port portion 14y is located directly below the connection port portion 14x, and is continuous with the internal space 14a from the lower end of the joint 14 at a predetermined height.

The inner end of the short straight pipe 16 is inserted and connected to the connecting port portion 14x of the joint 14 in which the lower end portion of the main bar 12 has entered. The outer end of the pipe 16 is open to the side surface (outer peripheral surface) of the concrete 11.
Similarly, the inner end of the straight pipe 17 is inserted and connected to the connection port portion 14 x of the joint 14 in which the lower end portion of the core bar 13 is inserted, and the outer end thereof is open to the side surface of the concrete 11.

The tube 17 is longer than the tube 16 because the core muscle 13 is disposed inside the main muscle 12. As shown in FIG. 3, the pipe 16 extends so as to be orthogonal to the side surface of the concrete 11, but the pipe 17 is arranged with respect to the side surface of the concrete 11 in order to avoid interference with the joint 14 into which the main reinforcement 12 has entered. It extends diagonally.
The internal spaces of the pipes 16 and 17 provide exhaust passages 16a and 17a that function as described below.

The inner end of a short straight pipe 18 is inserted and connected to the connection port portion 14 y of the joint 14 in which the lower end portion of the main bar 12 has entered, and the outer end thereof opens to the side surface of the concrete 11. Similarly, the inner end of the straight pipe 19 is inserted and connected also to the connection port portion 14 y of the joint 14 in which the lower end portion of the core bar 13 has entered, and the outer end thereof opens to the side surface of the concrete 11.
The dimensions of the pipes 18 and 19 and the arrangement seen from above are the same as those of the pipes 16 and 17, and the pipes 16 and 17 are also arranged directly below. The inner spaces of the pipes 18 and 19 provide lower passages 18a and 19a that perform the operations described later.

  The pipes 16 to 19 are made of, for example, vinyl chloride resin. The tubes 16 to 19 are inclined so as to become higher toward the outer end. In other words, the exhaust passages 16a and 17a and the lower passages 18a and 19a have an upward slope toward the outer end, and the outer end is higher than the inner end. The height difference between the outer ends and the inner ends of the exhaust passages 16a, 17a and the lower passages 18a, 19a is set to 1/2 or more, preferably more than the diameter of the exhaust passages 16a, 17a. The angles of the exhaust passages 16a and 17a and the lower passages 18a and 19a are about 1 to 20 °. In the present embodiment, all the passages 16a to 19a are set at an equal angle.

  The precast column 10 having the above-described configuration is joined to the joint portion 20 (lower structure portion of the building) shown in FIG. The joint 20 is a portion where a lower-floor precast column and a beam (both not shown) having the same configuration as described above are joined, and between the upper surface of the lower-floor precast column and the end surface of the beam. It is configured by placing concrete 21 in the formed space. The main reinforcement 22 and the core reinforcement 23 of the precast column on the lower floor are embedded in the concrete 21, and the upper end portion protrudes from the upper surface of the concrete 21.

  With the precast column 10 suspended and supported, the precast pillar 10 is lowered so that the upper ends of the main bars 22 and 23 enter the lower part of the internal space 14a of the joint 14. Thereby, in the joint 14, the main bars 12 and 22 face each other in a substantially straight line, and the core bars 13 and 23 face each other in a substantially straight line.

  A spacer (not shown) is placed in advance on the upper surface of the concrete 21, and the precast pillar 10 is placed on this spacer, so that the lower surface of the concrete 11 and the upper surface of the concrete 21 are placed as shown in FIGS. 2 and 4. A narrow joint space 30 is formed therebetween.

  Next, a mold frame 35 is installed on the upper surface of the concrete 21 so as to be along the side surface of the lower end of the concrete 11 of the precast column 10, thereby closing the joint space 30.

  Next, mortar 40 (filler) is filled. Note that the outer end openings of the pipes 16 to 19 of the precast pillar 10 (exhaust end openings of the exhaust passages 16a and 17a and the lower passages 18a and 19a) are all closed by plugs 36 in advance. The plug 36 is made of rubber, for example, and has an air vent passage formed of a notch or a through hole.

A selected one of the plurality of pipes 18 and 19, for example, a plug 36 fitted to the pipe 18, is removed, and a mortar injector nozzle is pressed here to inject the mortar 40 while applying pressure. The mortar 40 passes through the inner passage 14a of one joint 14 through the lower passage 18a or the injection passage of the selected pipe 18, and fills the joint space 30. As the injection continues further, the mortar 40 fills the lower passages 18a, 19a that were not selected. The lower passages 18a and 19a that are not selected satisfy the role of the exhaust passage for discharging the air in the joint space 30 and the internal space 14a of the joint 14 in the same manner as the exhaust passages 16a and 17a.
When the injection is further continued, the mortar 40 fills all the exhaust paths 16a and 17a after filling the internal spaces 14a of all the joints 14.

  When the mortar 40 finishes filling the exhaust passages 16a and 17a, the mortar 40 leaks from the air vent passages of the plugs 36 attached to the exhaust passages 16a and 17a. The operator sees the leakage of the mortar 40, finishes the injection, removes the injection nozzle from the selected lower passage 18a, and closes the lower passage 18a with a plug 36.

  When the mortar 40 filled as described above is cured, the joining of the precast column 10 to the joint portion 20 is completed. Note that after the mortar 40 is cured, all the plugs 36 are removed.

  In the joined state, the main bars 12 and 22 are connected to each other through the joint 14 and the mortar 40 in the joint 14. Similarly, the core bars 13 and 23 are also connected to each other through the joint 14 and the mortar 40 in the joint 14. The

  In the process of filling the mortar 40, the air in the joint space 30 and the air in the internal space 14a of the joint 14 are pushed up by the mortar 40 and discharged from the exhaust passages 16a and 17a. Since the exhaust passages 16a and 17a have an ascending slope that increases toward the outer end, when the mortar 40 passes through the upper end portion of the internal space 14a of the joint 14 and the exhaust passages 16a and 17a, an air pool is generated. Can be surely prevented. Therefore, since air does not remain in the joint 14 and is filled with the mortar 40, the connection strength between the main bars 12 and 22 and the core bars 13 and 23 can be further increased. Moreover, since air does not remain in the exhaust passages 16a and 17a and can be filled with the mortar 40, it is possible to prevent the cross-sectional area of the concrete 11 bearing a compressive load from being reduced, and the strength of the concrete 11 can be further increased.

  In the present embodiment, since the lower passages 18a and 19a also have an ascending slope that increases toward the outer end, even in the lower passages 18a and 19a that are not selected as the injection passage and function as the exhaust passage, good air can be obtained. I can do it. Further, since the lower passage 18a serving as the injection path has a downward slope with respect to the mortar injection direction, the injection can be performed smoothly.

Next, another embodiment of the present invention will be described. In these embodiments, components corresponding to the preceding embodiments are denoted by the same reference numerals in the drawings, and detailed description thereof is omitted.
In the first embodiment, the inner ends of the inclined pipes 16 and 17 are inserted and connected to the connecting port portion 14x whose center axis is horizontal, but in the second embodiment shown in FIG. 6, the connecting port portion 14x ' The central axis is inclined at the same angle as the inclination of the tubes 16 and 17. Thereby, the support of the inner ends of the tubes 16 and 17 can be strengthened. Although not shown, the same applies to the lower connecting port.

In the second embodiment of FIG. 6, since the central axis of the connection port portion 14x ′ of the joint 14 is inclined corresponding to the pipes 16 and 17, the joint 14 is not a versatile structure.
In the third embodiment shown in FIGS. 7 and 8, the central axes of the connection ports 14x and 14y of the joint 14 are horizontal as in the first embodiment. The pipes 117 and 119 connected to the joint 14 in which the core bar 13 is inserted are bent in a heated state, and the first portions 117x and 119x having a short straight tube extending horizontally from the inner end and the first portions 117x and 117x, It has straight tubular second portions 117y and 119y extending from 119x to the outer end. Since the first portions 117x and 119x are horizontal, the inner ends thereof are firmly inserted and supported by the connecting port portions 14x and 14y whose central axes are horizontal. The exhaust passages 117a and 119a can ensure a rising slope by the inclination of the second portions 117y and 119y. The pipe connected to the joint 14 in which the main reinforcement 12 has entered may be bent in the same manner.

  In the fourth embodiment shown in FIG. 9, the pipes 117 ′ and 119 ′ connected to the connection ports 14x and 14y are not bent, but the first parts 117x ′ and 117b made of straight pipes that are separate from each other. 119x ′ and second portions 117y ′ and 119y ′ are connected by an elbow pipe 200. In the fourth embodiment, the same effects as those in the third embodiment can be obtained.

In the fifth embodiment shown in FIG. 10, the features of the elbow pipe 200 are utilized to the maximum extent. This elbow pipe 200 not only allows the exhaust path 117a of the pipe 117 'to have a rising slope as in the fourth embodiment, but also the direction of the first part 117x' and the second part 117y 'when viewed from above. Can be changed. As a result, the arrangement, density, and the like of the exhaust passage 117a can be changed as appropriate. Further, when more joints are arranged, interference between the exhaust passages can be avoided by changing the angle of the second portion 117y ′ of the pipe 117 ′ using the elbow pipe 200.
In the fifth embodiment, the tube 119 ′ has the same structure as the tube 117 ′ and is disposed directly below the tube 117 ′, but illustration and detailed description thereof are omitted.

  In the sixth embodiment shown in FIG. 11, the main reinforcement (not shown) of the precast column 10 and the core reinforcement 13 are screw reinforcing bars. An internal thread 114b is formed on the inner periphery of the upper end of the joint 114, and the lower ends of the main and core bars 13 are screwed together. The upper end portion of the reinforcing bar 23 of the joint portion 20 enters deeply into the internal space 114 a of the joint 114. Even when this joint 114 is used, the structures of the first to fifth embodiments can be applied.

The present invention is not limited to the above embodiment, and various forms are possible. For example, only the long exhaust passage 17a may have an upward slope, and the short exhaust passage 16a may be horizontal. This is because if the exhaust path is long, air accumulation is likely to occur, and therefore the effect of the upward gradient becomes remarkable.
The tube forming the exhaust path may be a pressure resistant flexible hose. In this case, it is possible to form an exhaust path having an upward slope while being curved.
The middle part of the exhaust path may be made up-gradient, the inner end vicinity and the outer end vicinity may be made horizontal, the outer end vicinity may be made horizontal, and other parts may be made up-gradient.

  In all the above embodiments, the lower passage has the same structure as the exhaust passage, but the lower passage may be horizontal.

The lower end of the joint may be located slightly above the concrete lower surface. In this case, the lower end opening of the joint is continuous with a hole formed in the lower surface of the concrete.
The stopper 36 may not be attached at the start of mortar injection, but may be attached when mortar leaks from the injection path or the exhaust path.

As shown in the above embodiment, when mortar is filled into all joints via joint spaces, there may be only one injection path (lower side path), and this injection path is connected to one selected joint. You may make it connect.
When filling a mortar into a joint without going through a joint space, the mortar is injected from an injection path (lower passage) connected to each joint.
The present invention is applicable not only to precast columns but also to precast walls (precast members).

In 1st Embodiment of this invention, it is a longitudinal cross-sectional view which shows the state before joining a precast pillar to a joint part. In the same embodiment, it is a longitudinal cross-sectional view which shows the state immediately after joining the precast pillar to the joint part using mortar. FIG. 3 is a transverse sectional view taken along line III-III in FIG. 2. It is a longitudinal cross-sectional view which expands and shows the coupling for connecting the core of a precast pillar in FIG. 1, an exhaust passage, and a lower side channel | path. In the same embodiment, it is an expanded longitudinal cross-sectional view which shows the connection part of the pipe | tube and joint which form an exhaust path. FIG. 6 is a view corresponding to FIG. 5 showing a second embodiment of the present invention. FIG. 5 is a view corresponding to FIG. 4 showing a third embodiment of the present invention. FIG. 6 is a view corresponding to FIG. 5 showing the third embodiment. FIG. 5 is a view corresponding to FIG. 4 showing a fourth embodiment of the present invention. FIG. 10 is a view corresponding to FIG. 3 showing a fifth embodiment of the present invention. FIG. 7 is a view corresponding to FIG. 4 showing a sixth embodiment of the present invention.

Explanation of symbols

10 Precast pillars (precast members)
11 Concrete 12 Main bars (steel bars)
13 Core reinforcement (rebar)
14 Joint 14a Internal space 16, 17, 117, 117 'Pipes 16a, 17a, 117a Exhaust passages 18, 19, 119, 119' Pipes 18a, 19a, 119a Lower passage 20 )
21 Concrete 22 Main bars (steel bars)
23 Core reinforcement (rebar)
40 mortar 114b female screw part 117x, 117x ', 119x, 119x' first part 117y, 117y ', 119y, 119y' second part

Claims (6)

(A) concrete,
(B) a plurality of tubular joints having an internal space, embedded perpendicularly to the lower end of the concrete, and having an open end of the internal space open to the lower surface side of the concrete;
(C) a plurality of reinforcing bars embedded in the concrete and extending vertically, and having a lower end that enters an upper part of the internal space of the joint or is screwed into an upper end of the joint;
(D) a plurality of exhaust passages formed in the concrete, the inner end is connected to the upper end portion of the inner space of each joint, and the outer end is open to the outer peripheral surface of the concrete;
In the precast member to be joined to the lower component part by filling the filler with a plurality of reinforcing bars protruding upward from the lower component part into the internal space of the joint,
The coupling is formed with a connecting port portion that is continuous with the upper end portion of the internal space with the central axis being horizontal.
At least a portion of the exhaust path of the plurality of exhaust paths has a slope forming an upward toward the outer end, and set to higher than the outer end inner end of the exhaust passage, forming the exhaust passage The tube has a short first portion that extends horizontally from the inner end thereof, and a second portion that is formed longer than the first portion and extends upwardly toward the outer end, and the inner end of the tube. Is inserted and connected to the connecting port portion . First tube forming the exhaust passage, the second part consists of a separate straight tube, these first, according to claim 1, straight tube of the second portion is characterized in that it is connected by elbow Precast member. A joint in which a plurality of reinforcing bars have a plurality of main bars arranged along the outer peripheral surface of the concrete and a plurality of core bars arranged inside the main bars, and these core bars are inserted or screwed together. 3. The precast member according to claim 1, wherein the continuous exhaust passage has a slope that is directed upward toward an outer end, and a pipe forming the exhaust passage includes the first and second portions. . The precast member according to any one of claims 1 to 3, wherein all of the exhaust passages have a slope that is directed upward toward an outer end . Further, the concrete has a plurality of lower passages located below the exhaust passage, the inner ends of the lower passages are connected to the internal spaces of the joints, and the outer ends are the outer periphery of the concrete. Open to the surface,
At least part of the lower passage of the plurality of lower passage has a slope forming an upward toward the outer end, claim 1, wherein the outer end of the lower passage is higher than the inner end The precast member in any one of -4. The precast member according to claim 5 , wherein the lower passage has substantially the same structure as an exhaust passage connected to a common joint.

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