JPS58142008A - Method of clamping anchor bolt - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to a method for tightening anchor bolts to improve the degree of fixation of a steel structure or mechanical equipment to a foundation surface.

Generally, various structures and equipment are anchored to the foundation using anchor bolts, but the anchoring of 41KII structures is to prevent them from falling and to reduce the stress of the columns to the foundation using anchor bolts and pace plates. Since it has a purpose to convey, a high degree of fixation is required.

As one method of reinforcing this degree of fixation, a method of introducing an anchor pole IC axial force is often used.

Conventional methods for introducing axial force into anchor bolts include the torque control method and the nut rotation method.

The torque control method uses a torque wrench to control
Apply tightening torque to disperse the introduced axial force.
In addition, in the one-turn nut tightening method, the nut is tightened in two parts: a preliminary wire tightening and a final tightening. This method involves tightening the nut by rotating it approximately 30 degrees from the position shown below.

However, this method of introducing axial force has the disadvantage that it is impossible to inspect from the outside whether the predetermined axial force has been introduced or whether the nut is securely tightened. There is.

The present invention solves the drawbacks of the conventional tightening and fixing method of introducing axial force into the anchor bolt as described above, and allows for reliable and easy introduction of axial force into the anchor bolt for inspection and confirmation. A novel anchor bolt tightening method is proposed.

Hereinafter, embodiments of the present invention will be described with reference to the WA plane.

The shape of the anchor bolt body applied in the present invention is not limited to I#, but may be a general foundation bolt, and the nut used for tightening is % anchor as shown in Figure 1. Nut part 1g that screws into the bolt
A grip nut 1 of a special shape is used, which has a large diameter coupler portion 1h that is loosely fitted into the anchor bolt.

Note that the coupler portion 1bK is not provided with a screw.

In the present invention, temporary tightening is first performed using the grip nut 1 described above. The anchor bolts 2 are buried in the required length on the foundation concrete 3, and the anchor bolts 2 are passed through the anchor holes 5 of the base plate 4, which served as the lower end E1m of the column base. Place it on the foundation concrete 6. Then, a washer 6 having a wide area is inserted, the coupler part 1b is fitted with the washer 'tta<downward)K, the grip nut 1 is screwed onto the anchor pole 2, and temporarily tightened as shown in FIG.

Next, as shown in FIG. 5, a die 7 is set on the upper part of the grip nut 1, and a die cover 8 is loosely fitted on the outside of the die 7. Then, connect the reaction nut 9 to the anchor pole (2) which is concentrated upward from the die 7, and attach the center "
Insert the hole jack 10 and tighten the reaction nut 1 to fix it. In this case, the anchor bolt 2 is usually not long enough to insert the center hole jack 10, so when connecting the reaction nut 9,
At the upper end of the anchor bolt 2, like IIE511,
Screw on the reaction bolt 11 provided with the external thread 11-.

The reaction force nut 9 may be screwed onto the reaction force nut 11.

In this way, the preparation for introducing the axial force to the anchor pole 2 is completed, and then the center hole jack 10
Apply hydraulic pressure to this to extend it. Thereby, the center hole jack 10 uses the anchor bolt 2 as a reaction force via the reaction nut 9 to push the die 7 downward. Then, as the die 7 is pressed down, the large diameter coupler part 1h of the grip nut 10 is squeezed by the die 7, and is pressed into the outer circumference of the thread of the anchor bolt 2, and the lower end is shown in FIG. The sK bulging hem 1C is now formed, and the anchor bolt 2
At the same time, an axial force is introduced through the reaction nut 9 by the action of the center hole jack 100. At the same time, one grip nut 1 is tightened by ironing and crimping the anchor bolt 2, so that the bolt is fixed with an axial force introduced. It becomes K. After the fixing operation for introducing the axial force is completed, the reaction nut 9, reaction bolt 11. Center hole jack 10% die cover 8 and die 7 will be removed respectively.

In the method of the present invention, since one reaction force is applied to the anchor bolt itself E, the oil pressure of the center hole jack 1o is directly converted into the axial force of the anchor bolt 2. However, when the hydraulic pressure of jack 10 is released.

Since there is a return of a certain seismic intensity axial force, it is necessary to increase the hydraulic pressure of the jack that produces the required axial force in advance by that amount. Note that when introducing an axial force into the anchor bolt 2, the axial force is generally set at about 70 mm, which is the yield point of the material of the anchor bolt 2.

As explained above, one aspect of the present invention is to use a grip nut which has a nut part that is screwed onto an anchor bolt and a part of a large-diameter coupler that is loosely fitted into the anchor bolt, and which is screwed onto an anchor pole He. to temporarily tighten the base plate, then fit the die to the top of the grip nut and connect the reaction nut to the anchor bolt, i
? A center hole jack is interposed between the J die and the reaction force nut, and the die is pushed down by the action of the jack, and the grip nut is crimped to the outer periphery of the anchor bolt, so there are many excellent effects as shown below. can be played.

+11 Since a center hole jack is used to introduce axial force, a predetermined axial force can be introduced. In addition, since the movable direction is up and down, you can work even in narrow spaces, and
The entire construction can be done easily.

(2: Since the grip nut has the function of a conventional nut, temporary tightening and other operations can be performed in the same way as before. Moreover, the grip nut is squeezed with a die and screws into the threaded part of the anchor bolt. Since it is crimped in place, there is no risk of it coming loose.

(5: The shape of the grip nut is clearly different before and after introducing the axial force, so it can be inspected and confirmed by looking at it.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the grip nut used in the present invention, Fig. 2 is a longitudinal sectional view showing the anchor bolt in a temporarily tightened state, and Fig. 6 is a longitudinal sectional view showing the state when tension is introduced into the anchor bolt. FIG. 4 is a perspective view showing the state after the anchor bolt has been tightened. 1... Grip nut, 11I... Nut part,
IA... Part of coupler, 2... Anchor bolt, 3
river foundation concrete), 4... pace plate, 6...
・1117... Dice, 8... Dice cover, 9.
...Reaction force nut, 10...Center hole jack, 11...Reaction force nut Figure 1

Claims (1)

[Claims] The anchor bolt) K is screwed into the nut part and the grip nut, which forms part of the large-diameter coupler that is played by the anchor pole) K, is screwed into the anchor bolt, the pace plate is temporarily tightened, and then, At the same time as fitting a die to the upper part of the grip nut, a reaction nut is connected to the anchor bolt, a center hole jack is interposed between the die and the reaction nut, and the die is pushed down by the action of the jack. The grip nut is crimped onto the outer periphery of the anchor bolt. How to tighten anchor bolts.