JP3574978B2 - Anchor construction method and anchor construction equipment - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to an anchoring method and an anchoring device that bear a tensile load by inserting a high-strength steel material as an anchor material into a borehole and injecting grout to fix the anchor material in civil engineering work. is there.
[0002]
[Prior art]
When the water supply pressure increases while drilling an anchor hole with a boring machine, or when the rotational resistance of the bit increases, once the drill rod is pulled up by 10 to 20 cm, and when it returns to the normal value, drilling is performed again. Drilling has been done to increase the drilling efficiency.
[0003]
However, a lost bit such as a kronen bit conventionally used for anchor work is merely inserted into the tip of the drive shoe and has no locking device. Comes off the drive shoe.
Therefore, in drilling using a lost bit, when the water supply pressure or rotation resistance rises, the drilling is stopped immediately and the drill rod is rotated at that position, waiting for the water supply pressure and rotation resistance to return to normal values. Drilling had resumed.
[0004]
In order to solve the above-mentioned drawbacks, a structure in which a pin penetrating the lost bit and the drive shoe is driven so as to enable digging and digging is adopted.
[0005]
In addition, in anchor work in a pressurized groundwater layer, a check valve is required for the bit to prevent spring water during construction.However, in the past, it was manufactured separately in the valve case part and the bit part at the tip, and the valve was incorporated. Both were connected by welding or the like.
[0006]
[Problems to be solved by the invention]
However, if the excavation is resumed after the water pressure and the rotational resistance have returned to the normal values without digging, if the response is delayed, it may not be possible to recover to the normal values. For this reason, the excavation speed has to be reduced and the excavation must be performed carefully, which takes more time than necessary, and in some cases, excavation cannot be performed to the planned depth.
[0007]
In addition, in the structure where the pin is driven as described above so that digging can be performed, a rod is inserted into the boring rod used to cut the pin after the end of digging, and the rod is inserted. Although the pin was cut by applying a blow from the ground through the ground, not only it took time to put and take out the rod for cutting the pin, but also the cutting was damaged.
[0008]
Further, the conventional structure in which the valve case portion and the bit portion are manufactured separately requires time and effort for manufacturing.
[0009]
The present invention has been made in view of the above-described circumstances, and an anchor method and an anchor installation device capable of easily separating a lost bit from a boring rod when grouting and embedding an anchor bolt, and a check valve. A simple lost bit structure enclosed is provided.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the anchor method of the present invention involves engaging a lost bit with a latch at the tip of a bit catcher, inserting the bit catcher from the tip of a drive shoe to which a boring rod is connected, and removing the lost bit. A step of engaging an engaging portion with the tip of the drive shoe, a step of causing a boring machine to grip the boring rod, and a step of drilling an anchor hole in the ground, and after an anchor hole having a predetermined depth is drilled, Lowering the overshot attached to the end of the wire into the boring rod tube from the ground, engaging the retainer at the upper end of the bit catcher, pulling up the wire, and collecting the bit catcher to the ground; and After inserting the anchor material into the rod, the anchor is inserted through the gap between this anchor material and the rod. Withdraw the boring rod with grouted within, and more and a step of leaving a lost bit in the hole bottom.
[0011]
Further, in the anchor installation device of the present invention, a latch holding rod is slidably inserted with a spring interposed into a sliding pipe slidably inserted into a boring rod. , A first latch is pivotally mounted on the lower part, and a second latch is pivotally mounted on the upper part so as to be openable and closable. A bit catcher having a retainer attached to an upper end of the slide tube, and a base end detachably mounted on the first latch While being engaged, the lost bit having an engaging portion in the middle, the tip engages with the engaging portion in a state where the bit catcher is inserted from the tip, and the second bit so that the lost bit does not fall down. And a cylindrical drive shoe in which two latches are locked, and a boring rod is connected to the drive shoe via an adapter.
[0012]
Further, in the lost bit of the anchor installation device of the present invention, the bit portion at the tip and the valve case portion are integrally formed, and the bit portion is provided with a plurality of flow holes, and the tip of the hole of the valve case portion is formed. A ball serving as a valve body is inserted into the end of the hole of the valve case portion, and a valve seat is press-fitted in the middle of the hole.
[0013]
[Action]
After engaging the overshot attached to the tip of the wire with the retainer at the upper end of the bit catcher, pulling up the wire, the sliding tube moves upward in the boring rod against the spring force of the spring, Therefore, the tip of the latch holding rod comes down from the sliding tube. Since the first latch engaged with the base end of the lost bit is closed by this releasing operation, the bit catcher is pulled up.
[0014]
The lost bit is held by a second latch locked on the upper edge of the drive shoe so as not to fall down.
[0015]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
In FIG. 1, 100 is a bit catcher, 200 is a lost bit, and 300 is a drive shoe.
The bit catcher 100 is slidably mounted in the upper portion of the sliding tube 110 via a coil spring 121 so that the latch holding bar 120 is inserted into the sliding tube 110 from below.
The latch holding bar 120 is slightly resiliently urged onto the slide tube 110 by the coil spring 121.
A first latch 122 is provided at a lower end of the latch holding bar 120, and a second latch 123 is provided above the first latch 122 by springs (torsion coil springs) 122a and 123a. .
The first latch 122 is engaged with the base end of the lost bit 200, that is, the first latch engaging portion 221 of the valve case 220 (FIG. 2) of the lost bit 200 in an open state.
The second latch 123 is locked to the upper edge 310 of the drive shoe 300 in an open state, and holds the lost bit 200 and the bit catcher 100 so as not to fall downward.
A retainer 111 is attached to the upper end of the slide tube 110, and engages with the overshot 20 (FIG. 6) that has fallen from the ground when the collision occurs.
[0016]
As shown in FIG. 2, the lost bit 200 has a bit portion 210 at the tip end and a valve case portion 220 integrally formed, a plurality of flow holes 211 are formed in the bit portion 210, and a hole 222 of the valve case portion 220 is formed. In communication with the tip.
Reference numeral 223 denotes a valve seat, which is press-fitted near the entrance of the hole 222, and a spring pin 224 is fitted in an upper portion thereof as a valve seat stop just in case.
A ball 225 as a valve element is placed in a space from the valve seat 223 to the tip.
The valve seat 223 and the ball 225 are configured to function as a check valve, and the ball 225 shown in FIG. 1 moves from the position indicated by the broken line to the position indicated by the solid line to prevent spring water during construction. I have.
In the middle of the lost bit 200, an engaging portion 226 ((d) in FIG. 2) for engaging with the tip of the drive shoe 300 is provided.
[0017]
As shown in FIG. 3, the drive shoe 300 has a bifurcated engaging portion 320 formed at the distal end for engaging with the engaging portion 226 of the lost bit 200, and the upper end is connected to the boring rod 10 via the adapter 30 (see FIG. 3). (Fig. 1).
As described above, the second latch 123 is locked to the upper edge 310 in an open state (FIG. 1).
[0018]
Next, the anchor method will be described.
First, as shown in FIG. 4A, the first latch engaging portion 221 at the base end of the lost bit 200 is engaged with the first latch 122 at the distal end of the bit catcher 100.
[0019]
Next, as shown in (b), the boring rod 10 is connected to the drive shoe 300 via the adapter 30, the bit catcher 100 is inserted from the tip of the drive shoe 300, and the engaging portion 226 of the lost bit 200 is inserted. Is engaged with the forked engaging portion 320 at the tip of the drive shoe 300.
Next, as shown in (c), the boring rod 10 is gripped by a boring machine (not shown), and an anchor hole 41 is excavated in the ground 40 as shown in FIG.
[0020]
When the anchor hole 41 of a predetermined depth is drilled, the overshot 20 attached to the tip of the wire 21 is lowered from the ground into the pipe of the boring rod 10 as shown in FIG. When the sliding tube 110 is pulled upward after being engaged with the retainer 111, the sliding tube 110 rises against the resilience of the coil spring 121, but the latch holding bar 120 does not move while being engaged with the lost bit 200. Therefore, the inner fork 122b of the first latch 122 comes into contact with the inside of the distal end of the slide tube 110 and is narrowed. As a result, the outer fork 122c closes and the first latch engagement portion 221 at the proximal end of the lost bit 200 is closed. Is disengaged and the bit catcher 100 rises inside the boring rod 10, so that when the wire 21 is subsequently pulled up, the bit catcher 10 It is recovered pulled up on the ground as shown in FIG.
[0021]
Next, as shown in FIG. 7, after the anchor material 50 is inserted into the boring rod 10, the boring rod is injected into the anchor hole 41 through the gap between the anchor material 50 and the rod by grouting with cement paste, cement mortar, or the like. When the 10 is lifted, the grouting is completed with the lost bit 200 remaining at the bottom of the hole, and the anchor material 50 is fixed in the grout and fixed in the anchor hole 41 together with the grout.
[0022]
【The invention's effect】
According to the present invention described in detail above, the following effects can be obtained.
(1) Compared to the conventional structure in which the lost bit and the boring rod are connected by a pin, the locking structure by the bit catcher is used, so that the lost bit can be easily, reliably, and quickly separated, thereby improving work efficiency. (Claims 1 and 2).
[0023]
(2) It is no longer necessary to divide the lost bit into a bit portion and a valve case portion and connect them by welding or the like after storing the valve as in the conventional case, and the present invention simply forms the lost bit integrally and press-fits the valve seat. The structure is simple and the manufacturing cost is reduced (claim 3).
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of an anchor installation device of the present invention, wherein (a) is an entire view, (b) is a view taken along a line CC, and (c) is a cross-section taken along a line AA. Show.
2A and 2B are views of an embodiment of a lost bit according to the present invention, wherein FIG. 2A is a plan view, FIG. 2B is a partially cut front view, FIG. 2C is a bottom view, and FIG. (E) shows the side surface.
3A and 3B are diagrams of an embodiment of the drive shoe of the present invention, wherein FIG. 3A shows a front view, FIG. 3B shows a side view, and FIG.
FIG. 4 is a process chart showing one embodiment of the anchoring method of the present invention.
FIG. 5 is a process chart showing one embodiment of the anchoring method of the present invention.
FIG. 6 is a process chart showing one embodiment of the anchoring method of the present invention.
FIG. 7 is a process chart showing one embodiment of the anchoring method of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Boring rod 20 Overshot 21 Wire 30 Adapter 40 Ground 41 Anchor hole 50 Anchor material 100 Bit catcher 110 Sliding tube 111 Retainer 120 Latch holding rod 121 Coil spring 122 First latch 123 Second latch 200 Lost bit 210 Bit portion 211 Distribution Hole 220 Valve case portion 221 First latch engaging portion 222 Hole 223 Valve seat 225 Ball 226 engaging portion 300 Drive shoe 310 Upper edge 320 Bifurcated engaging portion

Claims (3)

Anchor method consisting of the following steps.
(1) The lost bit is engaged with the latch at the tip of the bit catcher, and the bit catcher is inserted from the tip of the drive shoe to which the boring rod is connected, and the engaging portion of the lost bit is engaged with the tip of the drive shoe. The step of combining.
(2) A step of causing a boring machine to grip the boring rod and drilling an anchor hole in the ground.
(3) After the anchor hole of a predetermined depth is drilled, the overshot attached to the tip of the wire is lowered from the ground into the pipe of the boring rod, and engaged with the retainer at the upper end of the bit catcher. And recovering the bit catcher to the ground.
(4) A step of, after inserting the anchor material into the boring rod, pulling up the boring rod while grouting the grout into the anchor hole through the gap between the anchor material and the rod, and leaving the lost bit at the bottom of the hole. A latch holding rod is slidably inserted through a spring into a sliding tube slidably inserted into the boring rod, and the latch holding rod has a first latch below. A bit catcher having a second latch pivotally mounted on the upper side so as to be openable and closable, and a retainer attached to an upper end of the sliding tube;
A lost bit having a base end detachably engaged with the first latch and having an engagement portion in the middle;
A tip end engages with the engagement portion in a state where the bit catcher is inserted from the end, and a cylindrical drive shoe in which the second latch is locked so that the lost bit does not fall down, A boring rod is connected to the drive shoe via an adapter. In the lost bit, a bit portion at a tip and a valve case portion are integrally formed, and a plurality of flow holes are formed in the bit portion so as to communicate with the tip of a hole in the valve case portion, and a hole in the valve case portion is formed. 3. The anchor construction apparatus according to claim 2, wherein a ball serving as a valve body is inserted into the tip of the valve, and a valve seat is press-fitted in the middle of the ball.

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