JPH07166650A - Joint-section joint sheath - Google Patents

Abstract

PURPOSE:To prevent the intrusion of paste by mounting a bellows cylinder extensible in the longitudinal direction and inserting cylinders at both ends of the bellows cylinder and circularly installing paste intrusion preventive ribs on the outer circumferences of the inserting cylinders. CONSTITUTION:An extensible bellows cylinder 2 is set up at a central section, inserting cylinders 3, 4 inserted into buried sheaths are fitted at both ends of the bellows cylinder 2, and paste intrusion preventive ribs 5 are mounted on the outer circumferences of the inserting cylinders 3, 4, thus forming a joint sheath 1. The bellows section 2 of the joint sheath 1 is contracted, and inserted into a joint section 15 between sideways arranged and built girders 11, 12, and the insides of buried sheaths 13, 14 are combined tightly by the paste intrusion preventive ribs 5. Accordingly, grouting in the buried sheaths can be conducted completely.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint joint sheath used in joints such as transverse girder joints of PC (prestressed concrete) precast girders.

[0002]

2. Description of the Related Art For example, when PC precast girders are horizontally connected, conventionally, a joint piece is used as a joint sheath, and a thin piece is inserted into the ends of the embedded sheaths of the precast girders or both ends of the embedded sheaths. A sheath was used and taped to prevent the cement paste from entering the embedded sheath when the joint concrete or joint mortar was cast.

[0003]

Such a conventional PC
When manufacturing a precast girder, it is necessary to widen the joints of the joints through which the horizontally tightened PC steel material is inserted in order to enable taping work.
There was an interval of 0 mm. Normally, the opening size of the joint between precast PC girders is about 110 mm,
Due to the above taping, it is necessary to widen the joints of the laterally tightened PC steel material when the girder is manufactured. In order to widen a part of the joint in this way, it is necessary to provide a recess on the lateral surface of the girder. For this reason, the inner surface of the concrete mold has been processed by attaching a plate for forming a concrete recess. The position where this recess is formed is
The position is different for each digit and cannot be fixed. Therefore, it is necessary to construct the inside of the form for each girder each time, and it is not possible to process the concrete form in advance, which is very troublesome.

Further, it is difficult to secure a perfect sealability when constructing a joint joint sheath by taping, and it is difficult to prevent cement paste from entering the embedded sheath when constructing a joint concrete or joint mortar. Very difficult. When the cement paste penetrates into the embedded sheath, there is a problem that the grout in the embedded sheath of the horizontal fastening PC steel material becomes incomplete.

In promoting precasting of concrete structures, how to connect precast members quickly and easily has been a problem. For example, how to process the joint joint sheath provided in the joint portion of the bridge girder (JIS A 5313, etc.) by the pretension method is one of the problems to be solved in order to save labor and simplify the process. Is.

In view of the above circumstances, it is an object of the present invention to provide a joint joint sheath which does not require taping and can be easily mounted in a joint and has a high sealing property.

[0007]

DISCLOSURE OF THE INVENTION The present invention was developed in order to achieve the above-mentioned object, and is a bellows tube which is expandable and contractible in the longitudinal direction, and an embedded sheath end of a precast member which is connected to both ends of the bellows tube. It is a joint joint sheath, characterized in that it is made of a synthetic resin cylindrical body having a fitting cylinder fitted therein. In this case, if one or two or more rows of paste intrusion prevention ribs having a diameter larger than the inner diameter of the embedded sheath are provided in a spiral shape on the outer diameter of the fitting cylinder, the intrusion of the paste into the embedded sheath is surely stopped. be able to. If the paste intrusion prevention rib is formed in a ring shape that is tilted rearward with respect to the direction of insertion when inserted into the embedded sheath, the joint joint sheath can be inserted smoothly when inserted into the embedded sheath. This is preferable because it is easy to ensure excellent sealing properties.

[0008]

The joint joint sheath of the PC precast member of the present invention has a narrow joint width, and can be attached to a place where the joint sheath cannot be manually attached, or a place deep within reach. This attachment is performed by inserting the bellows cylinder in a state in which the length in the longitudinal direction is reduced into the joint portion of the PC precast member through the joint gap, and letting both ends of the joint joint sheath be the end openings of the embedded sheath. The compressed state of the bellows cylinder is released, and the joint joint sheath is extended to connect the facing embedded sheaths to each other. Joint width 80 to 10
Even 0 mm is possible. A joint width of 80 to 100 mm is possible. In this way, when the ends of the facing embedded sheaths are connected to each other and the joint concrete or joint mortar is placed, the inside of the embedded sheath and the joints are insulated from each other, and the cement paste is prevented from entering the buried sheath. It is a thing.

When extended, the bellows cylinder, which is expandable and contractible in the longitudinal direction, has sufficient elasticity and is urged in the extending direction between the embedded sheaths, and it is necessary to have a sufficient sealing effect. . Further, when the bellows tube is contracted, the length of the entire joint joint sheath needs to be shorter than the joint opening dimension. Such requirements are satisfied by appropriately designing the material, wall thickness, shape of the bellows, that is, the length of the bellows, the depth of the peaks, the pitch, the roundness, etc., according to the joint width. If the bellows tube is formed in a spiral shape, there is an advantage that the contraction in the length direction becomes easy.

The joint joint sheath of the present invention is made of synthetic resin such as polyethylene or polypropylene that forms an elastic bellows cylinder. With such a resin, a bellows-shaped tubular body that expands and contracts by blow molding or the like can be manufactured. The wall thickness is 0.5 to 1 mm, and it is formed as an integral thin wall. When one or two or more rows of ring-shaped paste intrusion prevention ribs having a diameter larger than the inner diameter of the embedded sheath are provided so as to project in a headband shape on the outer circumference of the fitting cylinder, the paste of concrete or mortar in the joint portion is embedded in the embedded sheath. Can be completely blocked from entering. If this paste intrusion prevention rib is formed in a ring shape that is tilted rearward with respect to the direction of intrusion into the embedded sheath, it is easy to invade the joint joint sheath into the embedded sheath, and the paste intrusion prevention sealing effect is great. In addition, it is preferable that the joint joint sheath with a similar length be made to have a unified standard length. In this case, when the end portion is cut to an appropriate length and cut, the paste intrusion prevention rib is appropriately It is preferable to arrange them at appropriate intervals so that they remain.

Further, in this joint joint sheath, even if the embedded joint sheaths facing each other are not at right angles to the joints, the ends of the joint joint sheaths come into close contact with the embedded sheaths opposed to each other, and the seal is completed. In the above description, the horizontal fastening of the precast concrete bridge girder was described, but the joint joint sheath of the present invention is not limited to this, and the joint portion of the building structure, the joint of the concrete pavement, and the like. Precast PC for various structures and structures
It can be widely applied to joints of structures.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A joint sheath according to an embodiment of the present invention will be described with reference to the drawings. 1 is a side view of the joint sheath 1 in a state where the bellows tube 2 is freely extended, and FIG. 2 is a bellows tube 2
FIG. 3 is an enlarged view of a portion of the peak of FIG. 3, and FIG. 3 is an enlarged view of a portion A of FIG. 4 and 5 are side views of another embodiment, and FIG. 6 is an explanatory view when the joint sheath is inserted into the joint portion of the girder.

The joint sheath 1 shown in FIG. 1 is provided with an expandable and contractible bellows tube 2 at its central portion, and fitting tubes 3 and 4 for inserting the bellows tube 2 into the embedded sheath at both ends thereof. Ribs 5 for preventing paste intrusion are provided on the outer circumferences of the fitting cylinders 3 and 4. Table 1 shows an example of the dimensions of the example. (Dimension m
m)

[0014]

[Table 1] ──────────────────────────────── Joint width Bellows outer diameter × length Overall length Wall thickness Internal diameter ── ────────────────────────────── 80 50 50 × 80 120 120 0.5 38 38 100 50 × 100 160 0.5 0.5 38 130 50 × 130 200 0.5 38 General purpose 50 × 100 220 0.5 38 38 ──────────────────────────────── Figure 1 The one shown in Fig. 2 is a general-purpose type and is made of polyethylene. The fitting cylinders 3 and 4 have a length of 60 mm, and the intervals of the paste intrusion prevention ribs are 15, 20, 10, 15 from the left end, respectively.
mm. FIG. 2 shows the shape of the bellows, in which the spiral width 22 is 8.4 mm and the peak height 21 is 6 mm. FIG. 3 shows an example of the dimensions of the paste intrusion prevention rib 5, which has a height 51 of 1.5 mm and an inclination 52 of 0.5 mm.

The joint joint sheath 1 of the embodiment is shown in FIG.
It can be bent, as shown in. FIG. 5 is an explanatory view showing a method of using the joint joint sheath of the embodiment. The opening size of the joint portion 15 between the girders 11 and 12 that are installed side by side is 110 mm, for example. 160m in total length
The joint sheath 1 of the example of m is reduced in its longitudinal dimension and inserted into the joint portion 15 from above as shown by the arrow 16. At this time, it is preferable to use the jig 6 shown in FIG. The jig 6 is composed of a plate 61 sandwiching both ends of the bellows tube 2 of the joint joint sheath 1, a handle 62, and a handle connecting portion 63. The jigs 6 are used to sandwich the joint joint sheath 1 to reduce the bellows portion 2, and the girders 11 and 1 are installed side by side.
Inserted in the joint portion 15 between the two, the embedded sheaths 13, 14
When both ends are desired at the mouth of the joint and the grip 62 is released, the joint joint sheath is expanded and inserted into the embedded sheaths 13 and 14. At this time, the paste penetration preventing ribs 5 provided on the outer diameters of the fitting cylinders 3 and 4 form a complete seal portion in the embedded sheath. In this way, the embedded sheaths 13 and 14 can be tightly coupled within the joint portion.

Even when the embedded sheaths 13 and 14 are obliquely opposed to each other or the centers of the embedded sheaths are different from each other, the joint joint sheath of the embodiment can be bent, so that it is within a certain dimension. , Can be combined perfectly. The joint sheath of the embodiment allows the sheath in the joint to be easily and tightly connected while keeping the joint opening size to a minimum, and does not require the work such as taping, and the joint concrete or joint. When mortar was applied, cement paste no longer entered the sheath.

Next, the mounting test of the joint joint sheath of the embodiment and the confirmation test of the PC steel material insertion will be described. A wooden model shown in FIGS. 7 and 8 was manufactured. As full-scale test pieces, sheaths 82 and 72 having a diameter of 42 mm were attached to a fixed panel 81 and a movable panel 71, respectively, and workability of the joint joint sheath of the example was confirmed. As shown in FIGS. 7 and 8, workability was also confirmed when the installation angles of the sheaths 72 and 82 were set to 90 ° and 60 ° with respect to the panel surface and the center position of the sheath was shifted. Table 2 shows the test conditions, and the test was performed by changing the horizontal displacement a of the sheath center for each joint width. It was confirmed that workability was good under all the conditions of Table 2.

[0018]

[Table 2]

Next, using the full-scale concrete specimens 100 and 110 as shown in the elevation view in FIG. 9 and the plan view in FIG. 10, the joint joint sheath 1 of the embodiment is set and the PC steel material is set. It was inserted, the joint concrete 120 was driven in, and the joint joint sheath 1 was checked for strength by sufficiently compacting it with a bar-shaped vibrator. The dimensions of the concrete specimen are 500 mm in height 112 and 113 in sheath installation depth.
250 mm, concrete width 114 is 1000 mm,
The sheath positions 115 and 116 are each 200 mm, and the joint width 121 is 100 mm. The angle 117 is 60 degrees. The sheath 111 is 42 mmφ.

By driving concrete 120,
It was confirmed that the paste penetrated into the embedded sheath from the joint joint sheath 1. No penetration of paste occurred. The joint joint sheath was grouted, and the filling property of the grout was confirmed. The grout was perfect.

[0021]

According to the present invention, the inside of the sheath and the joint portion can be completely insulated, and the cement paste does not enter the embedded sheath when the joint concrete is poured. Therefore, the grouting in the embedded sheath can be performed completely. In addition, it does not require any work such as taping of the joint joint sheath, and can be easily installed and installed at an appropriate position, which eliminates the need for increasing the joint size when manufacturing the girder.

[Brief description of drawings]

FIG. 1 is a side view of a joint joint sheath according to an embodiment.

FIG. 2 is an enlarged view of the bellows tube of the embodiment.

FIG. 3 is an enlarged view of part A in FIG.

FIG. 4 is a side view showing the bending of the embodiment.

FIG. 5 is an explanatory diagram when the embodiment is inserted into the joint portion of the girder.

FIG. 6 is an explanatory diagram of a jig.

FIG. 7 is an explanatory diagram of a wooden model.

FIG. 8 is an explanatory diagram of a wooden model.

FIG. 9 is an elevational view of a concrete specimen for confirming the performance of the example.

FIG. 10 is a plan view of a concrete specimen for confirming the performance of the example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Joint sheath 2 Bellows tube 3, 4 Fitting tube 5 Paste intrusion prevention rib 6 Jig 11, 12 Girder 13, 14 Embedded sheath 15 Joint part 16 Arrows 100, 110
Specimen

Claims (3)

[Claims] 1. A joint made of a synthetic resin, which comprises a bellows tube which is expandable and contractible in a longitudinal direction, and a fitting tube which is connected to both ends of the bellows tube and is fitted into an end of an embedded sheath of a precast member. Part joint sheath. 2. The joint for joints according to claim 1, wherein one or two or more rows of paste penetration preventing ribs having a diameter larger than the inner diameter of the embedded sheath are provided on the outer circumference of the fitting cylinder in a spiral shape. sheath. 3. The joint joint sheath according to claim 2, wherein the paste intrusion prevention rib is a ring that is tilted rearward with respect to the direction of insertion into the embedded sheath.