JPH10131493A - Connecting method of tension material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a tension adding device or the end parts of tension materials from hopping so as to insure safety, even if the tension adding device is detached from the tension materials during adding tension to the tension material by mistake. SOLUTION: Before a tension adding device 20 is fitted to tension materials 3, 4, a pair of connecting members 5, 6 are coupled by screw so as to connect together them in a temporary holding state. After this connection, the tension adding device 20 is mounted between the tension materials 3, 4, and the respective tension materials 3, 4 are pulled in the direction of approaching them to each other so as to add tension to them. Under the condition of adding tension, screw-in of a pair of the connecting members 5, 6 is further promoted so as to bring the respective connecting members 5, 6 in contact with stoppers 14, 15, and then the tension adding device 20 is detached from the tension materiais 3, 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting method of a tendon used for joining a concrete structure such as a submerged tunnel or a bridge girder constructed on the sea floor.

[0002]

2. Description of the Related Art For example, in a submerged tunnel constructed on the seabed, a plurality of cylindrical boxes, which are concrete structures, are sequentially settled on the seabed and arranged in series, and the ends of these boxes are made of PC steel or the like. They are joined using a tendon.

That is, a tendon is inserted into each box and fixed, and the ends of the tendon are pulled out from the two joined boxes, and the ends are connected to each other while applying tension to these tendons. And the boxes are joined by the tension of the tendon.

[0004] Conventionally, for example,
As disclosed in Japanese Patent No. 38296, when connecting a pair of tendon members, the two tendon members are pulled out of the box, between the end of one tendon member and the end of the other tendon member, and straddle the two. A tension applying device (hydraulic jack) is provided so as to be stretched, and the tension applying device draws both tension members in a direction approaching each other to apply tension, and under this tension state, an end of one tension member is provided. Is connected to a connecting member attached to the end of the other tendon, and then the tension applying device is removed.

As a result, the tensions of the connected tendon members are balanced over their entire lengths, and the ends of the two boxes are brought into close contact with each other via a water-stopping gasket by this tension, thereby forming a series of tunnel structures. Be composed.

[0006]

By the way, the tension applying device is used only when applying tension to the tension member. Therefore, this tension applying device can be attached to the tension member relatively easily. In many cases, as a result, during the work of gradually applying tension to the tendon by the tension applying device, the tension applying device is accidentally disengaged from the tendon due to force imbalance or the like, and the tension applying device is repelled by the tendon. Or the end of the tendon material may jump greatly, causing an unexpected danger to the workers around it.

The present invention has been made in view of such a point, and an object of the present invention is to apply a tension applying device to a tension member by mistake while applying tension to the tension member. It is an object of the present invention to provide a tension member connecting method which can prevent the jumping of the tension applying device and the end portion of the tendon member and ensure safety even if the tendon member comes off.

[0008]

According to the present invention, in order to achieve the above object, a tension member is inserted into and fixed to a pair of concrete structures arranged opposite to each other.
A step of pulling out the ends of these tendons from the end face of the concrete structure;
A step of slidably attaching the connecting members connectable to each other by screwing each other with respect to the tendon, and attaching a stopper that regulates a range of sliding of the tendon, and an end of the one tendon and the other end A step of attaching a tension applying device between the end portions of the tendon members so as to straddle both of them, and a step of pulling the tendon members in a direction approaching each other to apply tension by the tension applying device. Connecting the connecting members by screwing them together, and removing the tension applying device from the tension member, wherein the pair of connection members are connected before attaching the tension applying device to the tension member. The members are screwed together and connected in a temporarily fixed state, and after this connection, a tension applying device is attached between both of the tendon members. The tensioning members are pulled in a direction approaching each other by a tensioning device to apply a tension, and in this tensioned state, the screwing of the pair of connecting members is further advanced to bring each tensioning member into contact with the stopper. After that, the tension applying device is detached from the tension member.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the structure of a portion where boxes for a submerged tunnel, which are concrete structures, are joined together. A plurality of tension members 3 and 4 such as PC steel materials are uniformly inserted and fixed in one cylindrical body 1 and the other cylindrical body 2 along the longitudinal direction of the peripheral wall. ing.

The ends of the tendons 3 and 4 are pulled out from the end surfaces of the boxes 1 and 2 respectively. The first connecting member 5 is connected to the leading end of one tendon 3 and the other end of the tendon 4. Second connecting members 6 are attached to the drawer ends.

The tension members 3, 4 are connected to each other via the connecting members 5, 6, and the tension of the two tension members 3, 4 causes the end of one box 1 and the other end. And the ends of the box 2 are joined to each other via a gasket 7 for stopping water so that no displacement occurs.

FIG. 2 shows an enlarged view of the structure of the connecting portion between the tension members 3 and 4, and metal crimping sleeves 9 and 10 are attached to ends of the tension members 3 and 4, respectively. , Screws 9a,
10a is engraved.

The first crimping sleeve 9 has a first
Is connected to the outer periphery of the other crimping sleeve 10 by a second
Are loosely fitted so as to be slidable, respectively. Each of the first and second connecting members 5 and 6 has an end wall on one end side, and is formed in a cylindrical shape whose other end side is open. Insertion ports 12 and 13 are formed in the end walls of the connecting members 5 and 6, and these insertion ports 12 and 13 are formed.
The crimping sleeves 9 and 10 of the tension members 3 and 4 are inserted into the inside,
Further, stoppers 14 and 15 composed of nuts for restricting the sliding range of the connecting members 5 and 6 to prevent the connecting members 5 and 6 from coming out are screwed to the distal end portions of these crimping sleeves 9 and 10.

A screw 5a is engraved on the inner periphery of the open end of the first connecting member 5, and a screw 5a of the first connecting member 5 is formed on the outer periphery of the open end of the second connecting member 6. Screw 6 corresponding to
a is engraved. And the screw 5 of the first connecting member 5
a and the connecting members 5 and 6 are connected to each other by screwing the screws 6a of the second connecting member 6 so that one tendon 3 and the other tendon 4 can be connected. .

FIG. 3 and FIG. 4 show an operation procedure for connecting the tendons 3 and 4 in order. Tendons 3, 4
As shown in (A) and (B), the insertion holes 1a,
1b. A crimping sleeve 16 (only one is shown) is attached to the rear ends of the tension members 3 and 4. A screw 16a is engraved on the outer circumference of the crimping sleeve 16, and the crimping sleeve 16 is inserted through the screw 16a. A nut 18 is screwed around the outer periphery of the nut 16.

An anchor plate 1 to which the nut 18 can be abutted is provided at the rear end of the insertion holes 1a and 1b.
9 (only one is shown) is provided. Reference numeral 20 denotes a protective cap that covers the outer periphery of the crimp sleeve 16.

When connecting the tension members 3 and 4, first, as shown in FIG.
From the state of (A), as shown in FIG.
The tension members 3 and 4 loosely inserted into the insertion holes 1a and 1b of the nuts 1 are respectively pulled to the front end side, and the nut 1 on the rear end side is pulled.
7 is pulled out until it comes into contact with the anchor plate 18.

Next, the first connecting member 5 is loosely fitted around the outer periphery of the crimping sleeve 9 at the tip of one of the tension members 3, and a stopper 14 made of a nut is screwed onto the tip of the crimping sleeve 9. The crimping sleeve 1 at the tip of the other tendon 4
The second connecting member 6 is loosely fitted around the outer periphery of the sleeve 0, and a stopper 15 made of a nut is screwed to the tip of the crimping sleeve 10.

Next, as shown in FIG. 4 (C), the first and second connecting members 5 and 6 are pulled toward the side where the nuts 14 and 15 are disposed, respectively, and a screw on the inner periphery of one connecting member 5 is provided. 5a and the screw 6a on the outer periphery of the other connecting member 6 are screwed together to connect the two connecting members 5 and 6. As a result, one tendon 3 and the other tendon 4 are connected in a so-called temporary fixing state, and the central axis of one tendon 3 and the central axis of the other tendon 4 coincide.

Next, as shown in FIG. 4 (D), a tension applying device 20 is attached between the one tendon 3 and the other tendon 4 so as to extend over both.
The tension applying device 20 includes, for example, a pair of clamps 21 and 22 and a pair of tension rods 23 and 24 provided between the clamps 21 and 22.

As shown in FIG. 5, each of the clamps 21 and 22 has a two-part structure including a clamp body 25 and a fastener 26, and the clamp body 25 is fitted to substantially half the circumferential surfaces of the crimping sleeves 9 and 10. A fitting recess 25a is formed in the fastener 26, and a fitting recess 26a is formed in the fastener 26 so as to fit on a substantially half circumferential surface on the opposite side of the crimping sleeves 9 and 10, respectively. , 27 so that the clamps 21, 22 are fixed to the crimp sleeves 9, 10 by tightening the screws 27, 27.

Insert holes 25b, 25b are formed in the clamp body 25 at positions opposite to each other with the crimping sleeves 9, 10 therebetween, and one end of the tension rods 23, 24 is connected to one clamp body 25. The other end of the other clamp body 2 is inserted into the insertion hole 25b of the other clamp body 2.
5 are loosely inserted into the insertion holes 25b, 25b, respectively.

Screws are formed on the peripheral surfaces of the tension rods 23, 24, and the insertion holes 25b,
25b, each tension rod 2 protruding outwardly
Nuts 28 and 29 are screwed to the ends of 3 and 24, respectively.

When attaching the tension applying device 20 to the tension members 3 and 4, the fitting recess 25 a of one clamp body 25 connected by the tension rods 23 and 24 is addressed to the outer periphery of the one crimp sleeve 9. Then, the fitting recess 25 a of the other clamp body 25 is addressed to the outer periphery of the other crimp sleeve 10, then a fastener 26 is attached to the one clamp body 25, and the one clamp body 25 is And the clamp 26 are fastened to fix the one clamp 21 to the one crimp sleeve 9, and the clamp 26 is attached to the other clamp body 25, and the bolt 27,
27 and the other clamp body 25 and the fastener 26
And the other clamp 22 is fixed to the other crimp sleeve 10.

After attaching the tension applying device 20 between the tension members 3 and 4 in this way, the nuts 29 and 29 at one end of each of the tension rods 23 and 24 are tightened using a tool. With this tightening, each clamp 2
The tendons 3 and 4 are drawn toward each other via the pulleys 1 and 22, and tension is applied to the tendons 3 and 4 by the pull. This tension can be controlled by the tightening amount of the nuts 29, 29. For example, a load of 2.5 tons is applied to each of the nuts 29, 29 to apply a tension of about 5 ton to the tension members 3, 4.

When the tension members 3, 4 are pulled in a direction approaching each other, the connecting members 5, which are connected in a temporarily fixed state,
With respect to 6, the tension members 3, 4 move by an amount corresponding to the extension thereof, and a play interval is generated between the end walls of the connecting members 5, 6 and the stoppers 14, 15.

Therefore, after that, the final fastening for further screwing the one connecting member 5 and the other connecting member 6 in the temporarily fixed state is performed, and as shown in FIG. The end wall is connected to the stopper 14 and the other connecting member 6
Are brought into contact with the stoppers 15, respectively.

After the work of the final tightening, as shown in FIG.
And further clamp body 2 of each clamp 21 and 22
5 and the fastener 26 are disassembled, and the tension applying device 20 is removed from the tension members 3 and 4. By the removal, the connecting members 5, 5 in which both the tension members 3, 4 are fully tightened.
6, the tension of the tension members 3 and 4 is balanced, and the one box 1 and the other box 2 are joined to each other with the balanced tension.

During the operation of screwing the connecting members 5 and 6, the through holes 5 formed in the peripheral surfaces of the connecting members 5 and 6 are used.
The work can be performed by inserting a tool such as a bur into the b and 6b.

When the tension applying device 20 is attached to the tension members 3 and 4 to apply tension, for example, the clamps 21 and 22 of the tension applying device 20 are used.
If the clamps 21 and 22 are displaced or disengaged during the work of applying the tension due to insufficient tightening of the tension members, the connecting members 5 of the tension members 3 and the tension members 4 Even if the connecting members 6 are temporarily connected to each other by temporary fixing, and the clamps 21 and 22 are erroneously shifted or disengaged, the tension of the tension members 3 and 4 may be instantaneously loosened. There is no danger that the tension members 3, 4 and the tension applying device 20 may jump off due to the reaction force.

Further, by temporarily fixing the connecting members 5 and 6, the central axis of one connecting member 5 and the central axis of the other connecting member 6 substantially coincide with each other before the tension applying device 20 is attached to the tension members 3 and 4. Since the straightening state is provided, there is an advantage that the tension applying device 20 can be easily and efficiently attached to the tension members 3 and 4.

The present invention can be applied not only to the case of the buried tunnel but also to the case where the bridge girders of the bridge are joined by using a tension member.

[0033]

As described above, according to the present invention, even if the tension applying device is accidentally disengaged from the tendon while the tension is being applied to the tendon, it can be prevented. It is possible to prevent the end of the tension applying device and the tendon material from jumping, thereby ensuring safety.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of a joint between boxes according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a connecting structure of a tendon at the joint.

FIG. 3 is a sectional view sequentially showing the first half of the connecting procedure of the tendon.

FIG. 4 is a sectional view sequentially showing the latter half of the procedure for connecting the tendon members.

FIG. 5 is a cross-sectional view of a tension applying device for applying a tension to a tension member.

[Explanation of symbols]

 3, 4 ... tension member 5, 6 ... connecting member 14, 15 ... stopper 20 ... tension applying device

Claims (1)

[Claims] 1. A step of inserting tension members into a pair of concrete structures arranged opposite to each other and fixing them, and pulling out ends of these tension members from an end face of the concrete structure; Attaching a connecting member slidable to the tension member at each end of the tension member, and attaching a stopper that regulates a range of sliding of the tension member; and one of the tension members Attaching a tension applying device between the end of the tension member and the end of the other tension member, and pulling the tension members in a direction approaching each other by the tension applying device, thereby forming a tension. , A step of screwing and connecting the connecting members to each other, and a step of removing the tension applying device from a tension member. In the connecting method of (1), before attaching the tension applying device to the tension member, the pair of connecting members are screwed to each other and temporarily connected to each other, and after this connection, the tension applying device is attached between both of the tension members. With the additional device, each tension member is pulled in a direction approaching each other to apply tension, and under this tension applied state, the screwing of the pair of connecting members is further advanced to bring each connecting member into contact with the stopper. Thereafter, the tension applying device is detached from the tension member.