JP3330107B2 - Structure of anchoring part of PC steel and method of injecting buffer material in anchoring part of PC steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for fixing a PC steel material and a method for injecting a buffer material into a fixing portion for a PC steel material.

[0002]

2. Description of the Related Art Conventionally, cables for prestressed concrete structures and steel structures have been used for PC steel strands, PC steel wires, and the like.
PC steel materials such as PC steel bars are used.
As shown in FIG. 9, an end portion of a PC steel material 27 is inserted into a PC steel hole 26 of an anchor head 25 and is fixed by a crimping grip 28. The crimping grip 28 is embedded in the concrete or a coupler 29 so that the repetitive load of the structure or the PC steel 27 is not applied.
The inside was filled with grout.

However, in the cable stayed bridge, the bridge, the membrane structure, and the anchoring structure of the PC steel material in the suspension roof, since the grout is not filled in the coupler 29, the repetitive load directly acts on the crimping grip 28. For this reason, the crimping grip 28 in the above-described PC steel fixing portion structure is required to have safety performance and fixing performance against repetitive loads, and this is confirmed by applying a predetermined stress amplitude to the crimping grip 28.
It is required to carry out a tensile fatigue strength test in which a repeated load of 100,000 times is applied.

[0004]

However, the anchoring structure of the PC steel material as described above can withstand the repetitive load of 2 million times required in the tensile fatigue strength test under the conditions shown in Table 1 below. Therefore, sufficient safety performance and fixing performance could not be secured.

[0005]

[Table 1]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a fixing structure of a PC steel material and a fixing of the PC steel material, which can secure sufficient safety performance and fixing performance for a tensile fatigue strength test. The purpose of the present invention is to provide a method of injecting a cushioning material in a part.

[0007]

Means for solving the above-mentioned problems are as follows. The invention of the anchoring structure of the PC steel material is based on the fact that the end of the PC steel material from which the outer peripheral coating has been peeled off is the outlet of the PC steel material hole of the anchor head. It is drawn out from the part, and is fitted into the fitting hole of the crimping grip via an insert, the fitting hole and the hole for the PC steel are filled with a cushioning material, and the entrance of the hole for the PC steel is
A spacer is fitted between a PC steel material and the spacer.
Is pushed into the hole for PC steel by a plate . PC steel materials are PC steel strand, PC steel wire, PC
Including any of the steel bars. Also PC steel
The outer surface of the core wire and side wire of the lead wire, the outer surface of the PC steel wire,
The outer surfaces each include a coating. Also Ann
The car head includes being screwed into the coupler. Also
The crimp grip is pushed to the anchor head by the end plate
Including what was attached. The cushioning material is epoxy resin,
Urethane resin, polybutadiene resin, unsaturated polyester
Tell resin, vinyl ester resin, silicone resin, metal
Ryl resin or polyolefin resin
Including. In addition, note that cushioning material should be
The insertion method involves removing the end of the PC steel material from which the outer peripheral coating has been peeled off.
From the exit of the PC steel hole in the car head
Fitted into the fitting hole of the wearing grip via an insert,
After press-fitting the cushioning material into the fitting hole of the crimping grip,
Fits the press-fit grip into which the PC steel material is inserted
At the same time, buffer material is inserted into the PC steel hole from the entrance.
Is press-fitted. Also the anchor head P
Apply a cushioning material to the inner surface of the C steel material hole and peel the outer coating.
Out the end of the PC steel from the exit of the hole for PC steel
Into the insertion hole of the crimp grip via the insert,
After press-fitting the cushioning material into the fitting hole of the crimping grip,
Crimping grip with impact material pressed into the exit of PC steel hole
It is characterized by being fitted. The cushioning material is epoxy tree
Fat, polyurethane resin, polybutadiene resin, unsaturated resin
Ester resin, vinyl ester resin, silicone resin,
One of methacrylic resin and polyolefin resin
Including that Also buffered from the entrance to the hole for PC steel
After press-fitting the material, insert a spacer into the entrance
Including. In addition, the crimp grip is used for the exit of the hole
After fitting, the fitting of the spacer to the inlet portion of the PC steel material for a hole
Including entering.

[0008] The tensile fatigue strength of PC steel increases. Also
High tensile fatigue strength of PC steel strand, PC steel wire and PC steel rod
It will be good. In addition, the outer surface of the core wire and side wire of the PC steel stranded wire, P
By coating the outer surface of C steel wire and the outer surface of PC steel rod,
And stress acting on the PC steel at the entrance of the fitting hole and the fitting hole
Absorbs frictional heat and is generated between the core wire and the side wire.
Protect them from frictional heat. Also of the crimp grip
P at the insertion hole and the hole for PC steel of the lower head
Reduces the notch force acting on C steel strand. Also crimping tool
The tip is protected with a coupler. Also, P
Alignment between C steel and PC steel hole is reliable and easy.
Wear. Also, fix the crimp grip to the anchor head.
Can be. Protection of PC steel from shear stress and frictional heat
Wear. In addition, the insertion hole of the crimping grip and the P of the anchor head
The cushioning material can be securely and easily pressed into the hole for the C steel material. A
Reliable and easy cushioning material for PC steel hole of anchor head
You can enter. In addition, shear stress and friction of PC steel
Can protect from heat. Also, press the buffer material into the hole for PC steel.
After that, the center of the PC steel material and the hole for the PC steel material is aligned with the spacer.
Can be performed reliably and easily. Spacer and PC steel
Alignment with the hole for PC steel can be performed reliably and easily.

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a fixing structure of a PC steel material according to the present invention (hereinafter referred to as a fixing portion structure) and a method of injecting a buffer material into a fixing portion of a PC steel material (hereinafter referred to as a method of injecting a buffer material). Will be described in detail with reference to the drawings. First, the structure of the fixing unit will be described, and then, a method of injecting a buffer material will be described.

FIG. 1A is a cross-sectional view showing a first embodiment of the fixing unit structure, FIG. 1B is a cross-sectional view taken along line AA of FIG.
(3) is a cross-sectional view taken along the line BB of (1). The fixing unit structure 1 is configured by fixing a plurality of PC steel strands 4 to an anchor head 3 into which a coupler 2 is screwed.

A plurality of side wires 6 are spirally wound around the outer periphery of the core wire 5 at the central portion of the PC steel wire 4, and a coating 7 made of a synthetic resin is applied to the outer surface of the core wire 5 and the side wire 6. ,
Further, an outer peripheral coating 8 is provided on the coating 7. This P
The distal end of the C steel strand 4 peels off the outer peripheral coating 8 and is inserted into the PC steel hole 9 of the anchor head 3.
The core 10 is aligned with the hole 9 for the PC steel material by the spacer 10 inserted into the hole.

Further, a crimping grip 11 is pulled out and crimped to the distal end portion led out from the outlet portion 9b, and the lower end portion is fitted into the outlet portion 9b of the hole for PC steel, and is pressed against the anchor head 3 by the end plate 12. ing. An insert 14 which is a wedge piece is fitted into the fitting hole 13 of the crimping grip 11, and a ridge 14 a having a sawtooth cross section formed on the inner surface and the outer surface thereof is formed on the outer surface of the PC steel strand 4 and the inner surface of the fitting hole 13. It does not bite and pull out from the crimping grip 11.

The fitting hole 13 and the hole 9 for PC steel material are filled with a buffer material 15 such as epoxy resin, polybutadiene resin, unsaturated polyester resin, polyurethane resin, vinyl ester resin, silicone resin, methacryl resin, polyolefin resin and the like. In particular, the cushioning material 15 between the insert 14 and the PC stranded wire 4 serves to double protect the PC stranded wire 4. This cushioning material 15 is the insert 1
4 or the inner surface of the PC steel hole 9 or press-fit into the fitting hole 13 and the PC steel hole 9 after crimping the crimping grip 11.

FIG. 3 shows a fixing unit structure 1 according to the second embodiment.
6, a bare PC stranded wire 19 in which the outer surfaces of the core wire 17 and the side wire 18 are not coated 7 is used in place of the PC stranded wire 4 described above. This is the same configuration as the fixing unit structure 1 of the embodiment. Even if such a bare PC steel strand 19 is protected by the cushioning material 15, the same effect as the fixing part structure 1 of the first embodiment can be achieved.

In addition to the first and second embodiments, the PC steel material may be a coated PC steel wire or a PC steel rod (not shown) or an uncoated PC steel wire or a PC steel rod (not shown). (Not shown) can also be used, and these can also provide the same effects as described above.

Next, a first embodiment of the method for injecting a cushioning material will be described in detail with reference to FIGS. In the present embodiment, the PC steel strand 4 of the first embodiment is used, and first, as shown in FIG. The crimping grip 11 is inserted into the PC steel hole 9 of the head 3, and is pulled out and crimped to a portion derived from the outlet 9 b. When the injection jig 20 is pressed against the top of the crimping grip 11 to press the cushioning material 15 such as epoxy resin into the fitting hole 13, the cushioning material 15 is inserted into the insert 14 and the PC.
The space between the outer surface of the steel strand 4 and the inner surface of the fitting hole 13 is filled. The cushioning material 15 is filled for each crimping grip 11 to protect the PC stranded wire 4 and the insert 14 from tensile load and rust.

Next, as shown in FIG.
1 is fitted into the outlet 9a of the hole 9 for PC steel, and the end plate 12
And fix it to the anchor head 3 with bolts 22. At this time, the part 8a of the PC steel wire 4 from which the outer peripheral coating has been peeled off and a part of the part 8b to which the outer peripheral coating has been applied are P
It is inserted into the hole 9 for the C steel material. Then, the cushioning material 15 is press-fitted from the inlet portion 9a of the hole as described above,
When this leaks from the outlet 9b, the filling is confirmed.

Next, a spacer 10 is inserted into the inlet 9a of the PC steel hole to align the core of the PC steel strand 4 with the hole 9 of the PC steel, and the plate 21 is attached to the anchor head 3 with bolts 23. Fix it. Therefore, the portion 8a from which the outer peripheral coating has been peeled is also covered with the cushioning material 15 in the hole 9 for PC steel, and this cushioning material 15
The state is filled from the steel material hole 9 to the fitting hole 13 of the crimping grip.

FIGS. 6 and 7 show the second method of the buffer material injection method.
In the embodiment, as shown in FIG. 6, first, a buffer material 15 such as an epoxy resin is applied to the inner surface of the PC steel hole 9 of the anchor head 3 in advance. Next, as shown in FIG. 7, the PC steel stranded wire 4 from which the outer peripheral coating 8 has been peeled is inserted into the PC steel material hole 9 to which the cushioning material 15 has been applied, and is drawn out from the outlet 9b. The crimping grip 11 is pulled and crimped to the bent portion. Next, a cushioning material 15 such as an epoxy resin is press-fitted into the fitting hole 13 of the crimping grip 11. When the press-fitting is completed, the crimping grip 11 is fixed to the anchor head 3 in the same manner as described above, and is inserted into the PC steel material hole 9. The buffer material 15 is press-fitted.

In the first and second embodiments, in addition to the above, the PC steel material may be a coated PC steel wire or a PC steel rod (not shown), or a non-coated PC steel stranded wire. , PC steel wire, and PC steel rod (not shown) can also be used, and these can also provide the same effects as described above.

Next, a description will be given of a tensile fatigue strength test of the PC steel strands 4 and 19 in the fixing part structures 1 and 16 of the first and second embodiments. The PC steel strand 4, 1
9 is a 15.2 mm diameter from seven wires, and the fixing part structure 1 of the first embodiment uses a PC steel stranded wire 4 in which a coating 7 is applied to the outer surfaces of a core wire 5 and a side wire 6. The fixing portion structure 16 of the second embodiment uses a bare PC stranded wire 19 in which the outer surfaces of the core wire 17 and the side wire 18 are not coated.

In this tensile fatigue strength test, PC steel stranded wires 4 and 19 having the above-mentioned fixing portion structures 1 and 16 at both ends were used.
As shown in FIG. 8, attached to the tensile fatigue tester 24,
A predetermined repetitive load is applied thereto to check the tensile fatigue strength. At this time, the elongation at the time of repeated upper limit stress and the elongation at the lower limit stress when the gauge length of the PC steel strands 4 and 19 was 1000 mm were as shown in Table 2 below.

[0045]

[Table 2]

The stress amplitude of the tensile fatigue strength is 25 kg.
/ ² or 30 kg / mm ² , when the PC steel strands 4 and 19 are subjected to a repetitive load of 2,000,000 times, it is necessary that the PC strands break at the parallel part as the minimum condition to withstand this. However, the PC steel strands 4 and 19 having the fixing unit structures 1 and 19 of the first and second embodiments satisfy this condition.

Table 3 shows the breaking conditions of the PC steel strands 4 and 19 provided with the fixing part structures 1 and 16 of the first and second embodiments, and Table 4 shows the results of the tensile fatigue strength test. It is shown. As a result, these PC steel strands 4, 1
It was confirmed that No. 9 did not break even with a repeated load of 2 to 3 million times.

[0048]

[Table 3]

[0049]

[Table 4]

[0050]

As described above, the tensile fatigue strength of the PC steel strand, the PC steel wire, and the PC steel rod is increased.

The outer surface of the core wire and side wire of the PC steel stranded wire, PC
The coating on the outer surface of the steel wire and the outer surface of the PC steel rod absorbs the stress and frictional heat acting on the PC steel at the entrance of the hole for the PC steel and the insertion hole, and friction generated between the core wire and the side wire. Protect these from heat. In addition, the PC in the insertion hole of the crimping grip and the hole for the PC steel material of the lower head is provided.
Reduces notch force acting on steel strands.

The crimp grip is protected by the coupler.

The alignment between the PC steel material and the hole for the PC steel material can be reliably and easily performed by the spacer.

The crimp grip can be supported by the anchor head.

The cushioning material can be securely and easily pressed into the fitting hole of the crimping grip and the hole for the PC steel of the anchor head.

The PC steel can be protected from shear stress and frictional heat.

After press-fitting the cushioning material into the hole for the PC steel material, the alignment between the PC steel material and the hole for the PC steel material can be reliably and easily performed by the spacer.

[Brief description of the drawings]

FIGS. 1A and 1B are cross-sectional views of a fixing unit structure according to a first embodiment, FIG. 1B is a cross-sectional view taken along line AA of FIG. 1A, and FIG.
FIG. 7 is a sectional view taken along line BB of FIG.

FIG. 2 is a cross-sectional view of a main part in (1) of FIG. 1, (2) is a cross-sectional view taken along line CC of (1), (3) is a cross-sectional view taken along line DD of FIG.
(4) is a sectional view taken along the line EE.

FIGS. 3 (1) and (2) are cross-sectional views of a PC steel stranded wire of a fixing portion structure according to a second embodiment.

FIG. 4 is a cross-sectional view of a method of injecting a cushioning material according to the first embodiment.

FIG. 5 is a cross-sectional view of a method for injecting a cushioning material according to the first embodiment.

FIG. 6 is a cross-sectional view of a buffer material injection method according to a second embodiment.

FIG. 7 is a cross-sectional view of a buffer material injection method according to a second embodiment.

FIG. 8 is a front view of the tensile tester.

FIG. 9 is a cross-sectional view of a conventional fixing unit structure.

[Explanation of symbols]

 1, 16 Fixing part structure 2, 29 Coupler 3, 25 Anchor head 4, 19 PC steel wire 5, 17 Core wire 6, 18 Side wire 7 Coating 8 Outer coating 9, 26 PC steel material hole 10 Spacer 11, 28 Crimping grip 12 End plate 13 Insertion hole 14 Insert 15 Buffer material 20 Injection jig 21 Plate 22, 23 Bolt 24 Tensile fatigue tester 27 PC steel

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) E04C 5/00-5/20 E04G 21/12 104

Claims (11)

(57) [Claims] 1. An end portion of a PC steel material from which an outer peripheral coating has been peeled is led out from an outlet portion of a PC steel material hole of an anchor head, and fitted into a fitting hole of a crimping grip via an insert. cushioning material is filled into a steel hole,
Spacer between PC steel and inlet of PC steel hole
Are fitted, and the spacer is placed in the hole for PC steel.
Fixing part structure of PC steel material, characterized in that it was pushed in . 2. PC steel material is PC steel strand, PC steel wire, P steel
The fixing part structure of a PC steel material according to claim 1, wherein the fixing part is any one of C steel bars. 3. An outer surface of a core wire and a side wire of a PC steel stranded wire,
3. The fixing part structure of a PC steel material according to claim 2, wherein the outer surface of the steel wire and the outer surface of the PC steel bar are coated respectively. 4. The fixing part structure for a PC steel according to claim 1, wherein the anchor head is screwed into the coupler. 5. The crimping grip is anchored with an end plate.
-Characterized by being pressed against the head
A fixing part structure of the PC steel material described in the above. 6. The cushioning material is epoxy resin or polyurethane resin.
Fat, polybutadiene resin, unsaturated polyester resin,
Nylester resin, silicone resin, methacrylic resin,
Characterized in that it is one of the polyolefin resins
The fixing part structure of a PC steel material according to claim 1. 7. An end portion of the PC steel material from which the outer peripheral coating has been peeled off.
Derived from the outlet of the PC steel hole in the anchor head,
Fits through the insert into the insertion hole of the crimp grip,
After press-fitting the cushioning material into the fitting hole of the crimping grip,
The crimped grip with the impact material pressed into the exit of the hole for PC steel
Into the PC steel material hole from the entrance.
In the anchoring part of PC steel, which is characterized by press-fitting impact material
How to inject buffer material. 8. An inner surface of a hole for a PC steel material of an anchor head.
End of PC steel material with buffer material applied and outer coating removed
From the exit of the hole for PC steel material and fit the crimp grip
Fit the insertion hole through the insert,
After press-fitting the buffer into the fitting hole, press-fit the buffer
Insert the grip into the exit of the hole for PC steel Features to do
A method of injecting a buffer material into a fixing portion of a PC steel material. 9. The cushioning material is epoxy resin or polyurethane resin.
Fat, polybutadiene resin, unsaturated polyester resin,
Nylester resin, silicone resin, methacrylic resin,
Characterized in that it is one of the polyolefin resins
9. The fixing part of the PC steel material according to claim 7 or 8.
Buffer material injection method. 10. A buffer material is pressed into the hole for PC steel from the inlet.
After insertion, it is necessary to insert a spacer into the entrance.
The fixing part of the PC steel material according to claim 7, wherein
How to inject cushioning material. 11. A crimping grip is provided at an outlet of a hole for a PC steel material.
After inserting into the hole, insert the spacer into the entrance of the PC steel hole.
9. The PC steel according to claim 8, wherein
A method of injecting a cushioning material at the attachment portion.