JPH1136300A - Installation method for anchor pressure receiving body and anchor pressure receiving body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an installation technique for an anchor pressure receiving body preventing the reaction force from the ground from being locally applied to radial arm sections constituting a pressure receiving body to cause cracks when the anchor pressure receiving body is installed on the irregular ground unlike when the conventional anchor is temporarily stretched, expanding the adaptable range of the irregular state of the ground, and capable of accurately transferring the tensile force applied to the anchor member to the ground. SOLUTION: Multiple pressure supporting arm sections 10 extended radially are provided, and spacer sections 9 for holding a pressure receiving body 6 at the separated state from the ground at the time of a temporary stretch are formed near the bottom face center section of the anchor pressure receiving body 6 formed with an anchor insertion hole at the center section. The temporary stretch is applied while the tip sections of the arm sections 10 are floated from the ground 1 via the spacer sections 9, a grout material is filled into the gap section between the pressure receiving body 6 and the ground 1 after the temporary stretch, a permanent stretch is applied after the grout material is hardened, and the pressure receiving body 6 is installed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for installing a pressure receiving body for an anchor applied to a ground anchor or the like applied to a slope or the like as a ground stabilizing means, and particularly to a ground having a lot of unevenness. The present invention relates to an improved technique for avoiding an obstacle such as a crack caused by a reaction force from the ground acting on the arm due to temporary tension when installing a pressure receiving body for an anchor having a plurality of arms extending radially.

[0002]

2. Description of the Related Art Conventionally, as a pressure receiving body for an anchor of this kind, a PC made of precast prestressed concrete has been used.
Those using a plate are widely known. When a PC pressure receiver made of prestressed concrete is used, a protrusion is formed near the center of the bottom surface of the pressure receiver that can be cut into the ground by the tension of the anchor, and the protrusion is temporarily grounded by the anchor. A technique has been disclosed in which a bite bite prevents an excessive reaction force from the ground from being generated at the tip of the cross-shaped arm, and shifts the bearing pressure to an evenly distributed state over time (actually). Fair 5-292
No. 50). However, the basic idea of this conventional pressure receiving body is to suppress the reaction force from the ground acting on the tip portion of the cross-shaped arm portion by the tension of the anchor, so that the projecting portion formed near the center of the bottom surface is used. As a result of adopting the method of cutting the ground into the ground, it was difficult to cope with the non-flatness to some extent. In other words, when the unevenness is large and the tip end of any of the cross-shaped arms is in contact with the ground in a state before the temporary tension in which the pressure receiving body is set on the ground, the temporary tension of the anchor causes Even if the protruding portion cuts into the ground, an excessive reaction force from the ground acts locally on the tip of the arm in contact with the ground, so that a bending moment acts on the arm. Therefore, the above-described method of dispersing the tension due to the bite of the protrusion cannot be used anymore, which causes a crack. In order to cope with this, there is a problem that if the ground is leveled or mortar or the like is sprayed to flatten the ground, the work load is increased.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional technical circumstances, and has as its object to be applied to a case where it is installed on a ground with a lot of unevenness. However, there is no local reaction force from the ground acting on the radial arm that constitutes the pressure receiving body at the time of temporary tension as in the past, and it does not cause cracks. The present invention provides a technique for installing a pressure receiving body for an anchor, which is capable of reducing the work load related to leveling by expanding the range, and transmitting the tension acting on the anchor material to the ground such as the ground properly. It is in.

[0004]

In order to solve the above-mentioned problems, the present invention has a bottom surface formed in a substantially planar shape, has a plurality of supporting arms extending radially, and a central portion for inserting an anchor. A spacer portion is formed near the center of the bottom surface of the pressure receiving body for an anchor made of a concrete structure having a through hole formed therein to hold the pressure receiving body away from the ground at the time of temporary tension, and the pressure receiving body is formed. When setting on the ground while inserting the anchor fixed to the ground side into the insertion hole for inserting the anchor, set the distal end of each of the arms via the spacer portion in a state of being lifted from the ground, The tension receiver is temporarily tensioned, and after the temporary tensioning, a gap between the pressure receiving body and the ground is filled with a grout material, and after the grout material is hardened, the tensioning is performed to place the pressure receiving body on the ground. Do It adopted the technical means to say. By forming a groove for guiding the grout material on the bottom surface of the arm portion, workability regarding filling of the grout material and reliability of the filling can be achieved. This concave groove is particularly effective in securing the grout material injection path in the case where the spacer portion slightly sinks into the ground due to temporary tension and the gap with the ground is reduced. Further, a plate-shaped supporting portion is formed between the arms, so that adaptability to soft ground can be improved.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, the anchor pressure receiving body installation technique according to the present invention basically employs an anchor pressure receiving body in which a space holding spacer formed near the center of the bottom surface is provided. A work process of setting the tip of each arm extending radially through the ground so that it is floated from the ground, and temporarily tensioning with an anchor fixed to the ground, and formed between those pressure receiving bodies and the ground It is sufficient that the gap is filled with a grout material, and after the hardening, the tensioning operation is performed by the anchor. The concrete structure of the other pressure receiving body, that is, the arm portion extending radially and the space holding can be used. The specific configuration of the spacer portion for use, the type of anchor, and the like are not questionable, and can be widely applied. That is, the pressure receiving member may be made of concrete formed by an appropriate construction method, such as precast prestressed concrete, or may be formed such that the planar shape of each radially extending arm portion is tapered, The length of the arm and the lateral arm may be changed. Further, a gap between the arms may be closed by a plate-shaped supporting portion having a bottom surface formed in substantially the same plane. Further, the size and height of the spacer for maintaining the interval can be freely set in consideration of the condition of the ground and the like. Further, the spacer portion may be formed integrally with the pressure receiving body or may be formed separately. When formed separately, the material may be hard resin, concrete, or steel. The mounting method may be joining by bolts or bonding by resin. In any case, it is sufficient if the spacer part can reliably hold a predetermined interval even when a part thereof is sunk into the ground due to the state of the ground at the time of temporary tension. Note that the anchor can be widely applied to any type of anchor such as various types of ground anchors.

Next, the installation work of the pressure receiving body for an anchor according to the present invention will be described. 1 to 7 are work explanatory diagrams showing work procedures related to the installation work. The anchor pressure receiving body according to the present invention is applied to each anchor 2 fixed at a predetermined position on the ground 1 by a known method in advance as shown in FIG. In the drawing, reference numeral 3 denotes a hole for the anchor 2, which is fixed to the ground 1 by inserting the anchor 2 into the hole 3 and injecting and hardening a grout material. Also,
Reference numeral 4 denotes a guide pipe for setting the pressure receiving member, and reference numeral 5 denotes a locking member provided on the outer peripheral portion of the guide pipe 4 for positioning the ground 1 having an L-shaped cross section. First, as shown in FIG. 2, the installation work of the anchor pressure receiver on the anchor 2 is performed via a hanging member 7 or the like connected to an insert or the like embedded in the pressure receiver 6 manufactured in advance in a factory or the like. The ground 1 is lifted by a crane or the like (not shown) and inserted into an anchor insertion hole 8 formed in the center of the pressure receiving body 6.
This is performed by lowering while setting the anchor 2 fixed on the ground 1 on the ground 1. At this time, the distal end portions of the radially extending substantially cross-shaped arms 10 constituting the pressure receiving body 6 are formed by the spacers 9 for maintaining the spacing formed so as to project downward near the center of the bottom surface of the pressure receiving body 6. The ground 1
It is important to set it in a state of being floated from above. That is, the pressure receiving body 6 is
A gap is actively formed between the lower surface of the arm 10 and the ground 1 so that the tip of the arm 10 is kept floating from the ground 1 during the temporary tension, so that the arm 10 is temporarily tensioned. The technical feature of the present invention lies in avoiding a reaction force from the ground 1 against the distal end portion and preventing a trouble such as a crack in the pressure receiving portion 6 due to the reaction force. The size of the gap formed between the lower surface of the pressure receiving member 6 and the ground 1 is determined by the size and height of the spacer portion 9, the state of the ground 1, and the like. And in the leveling work on the ground 1,
When the pressure receiving body 6 is set on the ground 1, it is sufficient to level the unevenness to such an extent that the reaction force from the ground 1 is not substantially transmitted to the tip of the arm 10 at the time of temporary tension due to the gap. , The work load is greatly reduced.

When the pressure receiving member 6 is set in the state shown in FIG. 2 with respect to the anchor 2, the operation shifts to the temporary tensioning operation shown in FIG. This temporary tensioning operation is performed by applying a predetermined tension to the anchor 2 using a well-known jack mechanism 11 or the like as shown in the figure. In that case,
The distal end of each of the arms 10 extending radially is set so as to float from the ground 1 as described above, and a reaction force from the ground 1 acts due to the temporary tension due to the interposition of the spacer 9 for maintaining the space. That will be avoided. In the provisional tensioning work, when a predetermined tension is applied to the anchor 2 by the jack mechanism 11, the fixing mechanism 12 fixes the anchor 2 to the provisional tension state as shown in FIG. 7 and the like, and the operation shifts to the work of filling the gap between the lower surface of the pressure receiving body 6 and the ground 1 with the grout material.

[0008] The grouting operation is started by closing the peripheral portion of the gap between the lower surface of the pressure receiving body 6 and the ground 1 with mortar or the like. That is, first, the mortar wall is formed so as not to block the grout material injection / exhaust passage 13 formed at each end of the arm portion 10 along the outer surface of each arm portion 10 extending radially, which constitutes the pressure receiving member 6. 14 closes hermetically. In this case, the lower injection / exhaust passage 13 may be closed. Further, if a sheet, bag, packing or the like for closing is previously provided along the peripheral portion of the pressure receiving body 6, the forming operation of the mortar wall 14 becomes easy. After the mortar wall 14 is formed, as shown in FIG. 5, an injection hose 16 connected to the grout material supply side such as a grout pump 15 is connected to the injection / exhaust passage 13 located at the upper side or the center of the pressure receiving body 6. The grout material is injected by being connected to the injection / exhaust passage 17 formed above the portion. As a result, the gap between the lower surface of the pressure receiving member 6 surrounded by the mortar wall 14 and the ground 1 is filled with the grout material. Injection / exhaust passage 13 formed at the tip of
And the injection / exhaust passage 1 formed at the center of the pressure receiving body 6.
It can be confirmed by the leak from No. 7. By forming a groove for guiding the grout material on the lower surface of each arm 10 as described later, it is possible to smoothly and reliably fill every corner. Further, an exhaust path for bleeding air can be further added to a portion where air tends to stay when the grout material is injected. Further, the grout material may be injected through an injection hose 16 directly inserted into the mortar wall 14 instead of the injection and exhaust passages 13 and 17.

When the grout material filled in the gap between the lower surface of the pressure receiving member 6 and the ground 1 has hardened, final final tension is executed again using the jack means 11 as shown in FIG. After re-fixing by the fixing means 12, a rust prevention cap 18 or the like is applied as necessary as shown in FIG. In addition, finishing work such as repair of the injection port 13 is appropriately performed as needed. Then, by repeatedly performing the above-mentioned installation work on the other anchors 2 sequentially, the pressure receiving bodies 6 are installed in a state of being aligned vertically and horizontally, for example, as shown in FIG. The pressure receiving body 6 installed in this manner is installed in a favorable state in which a reaction force from the ground 1 does not act on the arm portion 10 at the time of temporary tension, and no obstacle such as a crack or local stress acts. At the same time, a grout material is filled in the gap with the ground 1 and the adhesion to the ground 1 is good, so that the tension acting on the anchor 2 can be reliably and stably transmitted to the ground 1. it can.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing a pressure receiving member for an anchor according to the present invention. 9 to 12
FIG. 9 is a plan view, FIG. 10 is a front view, FIG. 11 is a bottom view, and FIG. 12 is a longitudinal sectional view of the pressure receiving body 6 as a first embodiment relating to a pressure receiving body for anchors. It is shown. As shown in the figure, the pressure receiving body 6 has four arms 10 arranged in a substantially cross shape extending radially, and the bottom surface is formed in a substantially planar shape. An insertion hole 8 for inserting an anchor is formed in the center of the pressure receiving body 6.
As described above, the pressure receiver 6 is fixed to the ground 1 by inserting the anchor 2 and tensioning the same. The grout material injection / exhaust passage 17 is formed above the insertion hole 8 so as to be in communication with the grout material. The upper surface of the pressure receiving body 6 is formed through the insertion hole 8 and the injection / exhaust passage 17. And the bottom are in communication. As shown in FIG. 12, a recess 19 for a fixing space is formed at the upper end of the insertion hole 8, and the fixing means 12 and the rust prevention cap 18 are housed in the recess 19. It is configured such that the upward projecting amount of the pressure receiving body 6 can be reduced. The injection / exhaust passage 17 serves to open the gap between the insertion hole 8 and the anchor 2 to the upper surface of the pressure receiving body 6 when the upper end of the insertion hole 8 is closed by the fixing means 12 during the temporary tension. As a result, it functions as a grout material injection path or an exhaust path. further,
As shown in FIG. 11, near the center of the bottom surface of the pressure receiving body 6, in the present embodiment, an interval in a state of projecting downward substantially in an L shape along the periphery of each corner of the connecting portion of each arm portion 10. The holding spacer 9 is formed, and the space between the pressure receiving body 6 and the ground 1 at the time of the above-mentioned temporary tension is maintained by the interposition of the spacer 9. In the figure, reference numeral 13 denotes a grout injection / exhaust passage formed in a hole shape at the tip of each arm 10, and reference numeral 20 denotes a female screw portion of an insert for attaching the hanging member 7 buried in the side surface of the arm 10. .

FIG. 13 is a longitudinal sectional view showing a modification of the first embodiment as a second embodiment relating to the anchor pressure receiving member. As shown in the drawing, the pressure receiving body 21 of the present embodiment is configured such that the lower part of the insertion hole 22 corresponding to the insertion hole 8 of the anchor 2 in the first embodiment is expanded to form a tapered portion 23, and the pressure receiving body 21 is installed on the anchor 2 It has a feature only in that the corners have a degree of freedom, and there is no substantial difference from the first embodiment in other points. FIG. 14 is a bottom view showing a modification of the first embodiment as a third embodiment relating to the anchor pressure receiving body. As shown in FIG.
Reference numeral 4 denotes the injection and exhaust passages 13 on the bottom surface of the first embodiment.
Is formed by forming a substantially cross-shaped concave groove 25 for guiding the grout material, which is communicated with the grout material, and guiding the grout material through the concave groove 25 when the grout material is injected into the gap between the ground 1 and the pressure receiving body 24. It has a feature only in that it can be filled smoothly and reliably, and there is no substantial difference from the first embodiment in other points. FIG. 15 is a longitudinal sectional view showing a modified example of the first embodiment as a fourth embodiment relating to the anchor pressure receiving body. As shown in the drawing, the pressure receiving body 26 of the present embodiment has a straight insertion hole without forming a fixing space recess at the upper end of an insertion hole 27 corresponding to the insertion hole 8 of the anchor 2 in the first embodiment. It is characterized only in that the configuration is simplified, and there is no substantial difference from the first embodiment in other points. In the present embodiment, the amount of protrusion of the fixing means 12 and the rust prevention cap 18 upward naturally increases.

FIGS. 16 to 18 show a fifth embodiment relating to a pressure receiving member for an anchor. FIG. 16 is a plan view thereof, FIG. 17 is a front view thereof, and FIG. 18 is a bottom view thereof. . The pressure receiver 28 of the present embodiment will be described by assigning the same reference numerals to the same components as those of the first embodiment.
The first embodiment is characterized in that a plate-shaped bearing portion 29 is formed between each of the arms 10 extending radially to constitute the portion 8 to improve adaptability to soft ground. There is no substantial difference. However, the pressure receiving member 2 in the present embodiment
In the work of filling the gap between the ground 8 and the ground 1 with the grout material, the gap is closed with mortar or the like along the outer periphery of the plate-shaped supporting portion 29 to fill the grout material. Note that, in the present embodiment, the plate-shaped supporting portions 29 are each of the arm portions 10.
Although it is formed in a wide state in which the front end portions are connected, it may be formed in a reduced form in which the middle portions of the respective arm portions 10 are connected.

In the above, the embodiments having partially characteristic features have been individually described. However, by combining the features of the respective embodiments as needed, various embodiments can be realized. It is possible. In addition, the injection / exhaust passages 13 and 17 formed for injecting the grout material are formed in such a manner that one passage is used also as the injection passage and the exhaust passage. It goes without saying that it can be formed as a dedicated passage for exhaust. Further, it is possible to form the injection / exhaust passage 13 in a groove shape.

[0014]

According to the present invention, the following effects can be obtained. (1) The temporary tension of the anchor according to the present invention is carried out in a state in which the respective distal ends of the radially extending arms constituting the pressure receiving member are separated from the ground and floated, so that the temporary tension from the ground due to the temporary tension. It is possible to eliminate the problem that a force is applied to the tip portion of the arm portion as in the related art, which causes a crack or is installed in a state where a local stress is still applied. (2) Further, since the tension of the anchor is performed in a state where the gap between the pressure receiving body and the ground is filled with the grout material after the temporary tension, the adhesion of the pressure receiving body to the ground is good, so that the anchor material is Can be reliably and stably transmitted to the ground. (3) The range of the non-landing state which can be applied is greatly expanded by the interposition of the spacer for maintaining the interval, and the leveling work on the ground is greatly reduced. (4) The structure is very simple because it is only necessary to provide an appropriate spacer portion near the center of the bottom surface of the anchor pressure receiving body. (5) If a groove for guiding the grout material is formed on the bottom surface of the arm portion, the grout material can be more smoothly and reliably filled. (6) By forming a plate-shaped supporting portion between the arms, adaptability to soft ground or the like can be improved.

[Brief description of the drawings]

FIG. 1 is a work explanatory diagram showing a work procedure in the present invention.

FIG. 2 is a work explanatory diagram showing the work procedure.

FIG. 3 is a work explanatory diagram showing the work procedure.

FIG. 4 is a work explanatory diagram showing the work procedure.

FIG. 5 is a work explanatory diagram showing the work procedure.

FIG. 6 is a work explanatory diagram showing the work procedure.

FIG. 7 is a work explanatory diagram showing the work procedure.

FIG. 8 is an installation state diagram showing an installation state of the anchor pressure receiving body.

FIG. 9 is a plan view showing a first embodiment of an anchor pressure receiving body.

FIG. 10 is a front view of the same.

FIG. 11 is a bottom view of the same.

FIG. 12 is a longitudinal sectional view of the same.

FIG. 13 is a longitudinal sectional view showing a second embodiment of the anchor pressure receiving body.

FIG. 14 is a bottom view showing a third embodiment of the anchor pressure receiving body.

FIG. 15 is a vertical sectional view showing a fourth embodiment of the anchor pressure receiving body.

FIG. 16 is a plan view showing a fifth embodiment of the anchor pressure receiving body.

FIG. 17 is a front view of the same.

FIG. 18 is a bottom view of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ground, 2 ... Anchor, 3 ... Drilling, 4 ... Guide pipe, 5 ... Locking member, 6 ... Pressure receiving body, 7 ... Hanging tool, 8 ... Anchor insertion hole, 9 ... Space maintenance Spacer part,
Reference numeral 10: arm portion, 11: jack mechanism, 12: fixing means, 1
3: Grout injection / exhaust passage, 14: Mortar wall, 1
5: Grout pump, 16: Injection hose, 17: Grout material injection / exhaust passage, 18: Rust prevention cap, 19: Depression for fixing space, 20: Internal thread of insert, 2
DESCRIPTION OF SYMBOLS 1 ... Pressure receiving body, 22 ... Penetration hole for anchor insertion, 23 ... Tapered part, 24 ... Pressure receiving body, 25 ... Groove material guiding groove, 26 ... Pressure receiving body, 27 ... Insertion hole for anchor insertion, 2
8 ... Pressure receiving body, 29 ... Plate bearing part

Claims (4)

[Claims] 1. An anchor receiving pressure comprising a concrete structure having a bottom surface formed in a substantially planar shape, a plurality of radially extending supporting arms, and a central portion having an insertion hole for anchor insertion. Near the center of the bottom surface of the body, a spacer portion is formed to hold the pressure receiving body separated from the ground at the time of temporary tension, and the pressure receiving body is provided with an anchor fixed to the ground side through an insertion hole for inserting the anchor. When it is set on the ground while being inserted through, the distal end of each of the arms is set in a state of being lifted from the ground via the spacer portion, and is temporarily tensioned by the anchor. A method of installing a pressure receiving body for an anchor, comprising: filling a grout material in a gap between the ground material and the ground; and hardening the grout material and then performing a main tension to install the pressure receiving body on the ground. 2. A concrete structure having a bottom surface formed in a substantially planar shape, having a plurality of radially extending arms, and having a through hole for inserting an anchor in a center portion, and near a center of the bottom surface. A spacer portion is formed to hold a state separated from the ground at the time of temporary tension, and temporary tension is applied by an anchor fixed to the ground side in a state where the distal ends of the arms are lifted off the ground via the spacer portion. A pressure receiver for an anchor, wherein the pressure receiver is configured to be implemented. 3. The pressure receiving body for an anchor according to claim 2, wherein a groove for guiding a grout material is formed in a bottom surface of said arm portion. 4. A pressure receiving body for an anchor according to claim 2, wherein a plate-shaped supporting portion is formed between said arms.