JP4778805B2 - Construction method of foundation pile - Google Patents

Description

  The present invention relates to a method for constructing a foundation pile in a pile foundation or the like, and more specifically, in an embedded pile construction method using a hollow ready-made pile, the pile head of the foundation pile (in this specification, “pile head” The top of the pile and the vicinity of the top are used as a concept that includes the “head of the pile” and the space inside the excavation hole on the top of the pile head. ) To any desired depth of the hollow pile, and relates to the construction method of the foundation pile that can strengthen the whole pile.

  In foundation construction methods for houses, apartment buildings, and other structures, a foundation pile that reaches the depth of the support layer is provided, and the foundation foundation for the structure is formed on the pile head of the foundation pile. It is widely used when constructing structures on liquefied ground.

  As an example of the foundation pile construction method in such a pile foundation, in the embedded pile construction method using a hollow ready-made pile, the root solidification liquid and the peripheral fixing liquid are placed in the excavation hole formed by an excavator such as an earth auger. After injecting cement milk, a hollow pile made of steel pipe or concrete is built, or after a hollow pile is built in the excavation hole, cement milk is injected as a rooting liquid through the hollow hole of the pile, The support layer is solidified, enlarged bulbs are created, and the surrounding ground and hollow piles are integrated.

  And on the foundation pile manufactured in this way, the foundation part of a structure is formed as mentioned above, and this foundation part is joined to the pile head.

  In such a pile foundation structure, the head of the foundation pile and the foundation part of the structure formed on it are generally joined as described above. In addition, since the pile head and the whole pile move together with the underground ground where the foundation pile is embedded and the foundation supporting the upper structure, the horizontal and rotational forces transmitted from the upper structure As a result, large bending moments and shearing forces are concentrated near the pile head.

  In particular, in soft ground and liquefied ground, when an earthquake or the like occurs, the ground displacement becomes larger, so the shearing force and bending moment generated near the pile head are even greater.

  In this way, as a ready-made pile to be used in order to withstand the bending moment and shearing force of the pile head that is generated when the superstructure and the underground ground including the foundation pile move synchronously and integrally, It is conceivable to increase the number of piles to be installed, or this method will increase the construction cost of the pile foundation.

  As a method of strengthening the pile head, the entire pile is not made large in diameter, but it is formed with a larger diameter from the pile head to a predetermined depth compared to other parts to satisfy the horizontal resistance. It has been proposed to reinforce a steel pipe (see Patent Document 2) by winding a steel pipe around the outer periphery of the pile extending from the pile head to a predetermined depth (see Patent Document 1).

Prior art document information of the present invention includes the following.
Japanese Patent Laid-Open No. 2004-132047 (column 0006, FIG. 1) JP-A-10-131176 (column 0002, FIG. 8)

  As mentioned above, the entire pile to be used has a large diameter by forming the pile head portion of the foundation pile with a larger diameter compared to other portions, or by reinforcing the pile head portion with steel pipes, etc. Compared to the case of increasing the number of piles to be used or the case, the construction cost of the pile foundation can be reduced.

  However, in order to form the pile head part of the foundation pile with a larger diameter compared to other parts, the invention described in Patent Document 1 excavates a pile hole having a large diameter part near the pile head position, and excavates it. After placing a hollow pile in the hole, it is necessary to fill the large-diameter part of the pile hole with a solidified material, which is accompanied by an increase in work man-hours and an increase in the materials used compared to the conventional embedded pile method. .

  The same applies to the method described in Patent Document 2 in which a steel pipe is wound around the pile head to reinforce it, and the outer circumference of the pile head is dug down to wind the steel pipe around the pile head, and then the steel pipe is wound up and backfilled again. This is accompanied by an increase in work man-hours such as the need for work and an increase in materials used such as steel pipes.

  For this reason, the construction period necessary for constructing the pile foundation becomes longer and the construction cost increases.

  If cement milk is filled in the drilling hole, the slime remaining in the drilling hole will rise due to the difference in specific gravity. Therefore, in the hollow space of the hollow pile, there is slime or cement milk containing a large amount of slime in the head portion of the pile, which will be cured as it is. Does not contribute to anything.

  The present invention has been made to eliminate the above-mentioned disadvantages of the prior art, and is relatively simple and low-cost in the work process of the embedded pile method using hollow piles. In addition to preventing the drop, the pile head can be further strengthened, the strength and rigidity of the pile can be increased to reduce the thickness of the hollow pile, or the pile diameter can be selected to be small It aims at providing the construction method of the foundation pile which can also aim at cost reduction.

In order to achieve the above object, the foundation pile construction method of the present invention is a slime existing in the hollow space 32 of the hollow pile 30 built in the excavation hole 40 in the embedded pile construction method using a hollow ready-made pile. Or when the cement milk is in a liquid or gel form, the inside of the hollow space 32 extends from the pile head 31 to an arbitrary depth corresponding to the degree of reinforcement exerted on the entire pile, or a range reaching the pile bottom or the vicinity thereof. Inserting a removal container, containing the slime and / or cement milk in the hollow space, and discharging and removing it to the outside;
Placing a lid (pile inner lid 74) at the bottom of the hollow space from which the slime and / or cement milk has been removed;
Filling the hardened material with the filling / curing material on the lid (the pile inner lid 74) ,
The pile head 31 of the hollow pile 30 is disposed at a predetermined depth in the excavation hole 40, and a cylindrical tube is formed in the excavation hole from the pile head 31 to the upper end of the excavation hole 40. The sheet pile 60 is inserted, and the slime and / or cement milk is removed through the space surrounded by the cylindrical sheet pile 60, the lid 74 is disposed on the bottom of the hollow space, and the filling / curing material is filled. Done,
After filling with the filling / curing material, the lower end opening of the cylindrical sheet pile 60 is covered with a lower lid body 68, and the upper end opening of the cylindrical sheet pile 60 is covered with an upper lid body 67. Item 1).

  Ready-mixed concrete can be used as the filling / curing material (Claim 2).

Furthermore, the hollow space is filled with mortar as the filling / hardening material, the hollow pile has an outer diameter smaller than the inner diameter of the hollow pile 30, and a length at which the upper end substantially reaches the top of the hollow pile. If a core pile is inserted, the pile can be further strengthened (Claim 3 ).

Further, when removing the slime and / or cement milk, the removal container 10 is formed so as to be able to cover the space where the slime and / or cement milk to be removed is present, and the slime and / or cement milk is contained therein. A removal container body 11 having an opening 13 for opening the collection space on the bottom side, and an openable / closable cover plate 14 for covering the opening 13 of the removal container body 11. Prepare what you have,
The removal container 10 is inserted into the hollow space 32 of the hollow pile 30 from the bottom,
Opening the lid 14 and introducing the slime and / or cement milk into the collection space 12;
The slime and / or cement milk in the hollow space 32 can be removed by covering the opening 13 with the lid plate 14 and extracting the removal container 10 from the hollow space 32 (Claim). 4 ).

  According to the construction of the present invention described above, according to the foundation pile construction method of the present invention, the following remarkable effects not found in the prior art can be obtained.

  Slime and cement milk containing slime are removed from the hollow space 32 of the hollow pile 30 including the pile head 31 to be reinforced, and the cement milk containing filler and hardened material is filled in the hollow space 32 after removing these. The pile head 31 or the entire hollow pile 30 can be strengthened easily and at low cost by filling mortar as a pre-process for inserting ready-mixed concrete or core pile with high strength after hardening. did it.

  Moreover, by placing a pile inner lid 74 at the bottom of the hollow space 32 from which slime and cement milk have been removed, as a filling / hardening material, ready-mixed concrete or core pile having a higher specific gravity than cement milk can be used as a cement. The pile head 31 or the entire hollow pile 30 could be hardened without being submerged in the milk.

  Moreover, when the pile head 31 of the hollow pile 30 is arrange | positioned in the predetermined depth in the excavation hole 40, removal of the said slime and / or cement milk, arrangement | positioning of the pile inner cover 74, and fresh concrete of The filling was performed with the cylindrical sheet pile 60 inserted into the excavation hole 40 extending from the pile head 31 to the upper end of the excavation hole 40, so that the inner wall of the excavation hole 40 collapsed during the operation. It was possible to prevent the mud from soil and sand and spring water from entering the hollow pile 30.

  Moreover, after filling the ready-mixed concrete as a filling / hardening material, the lower end opening of the cylindrical sheet pile 60 is covered with the lower cover 68 and the upper end opening is covered with the upper cover 67 so that impurities are mixed into the filled ready-mixed concrete. I was able to prevent it.

  Further, since the sheet pile 60 occupies the space above the pile head of the foundation pile, the pile head 31 is protected from contact with, for example, a back-hoe bucket during subsequent operations such as root cutting. In addition, it was possible to prevent a decrease in strength of the pile head 31 due to damage due to contact.

  By removing the slime and / or cement milk in the hollow space 32 of the pile head 31 with the removal container 10 having the above-described configuration, the removal container 10 can be inserted into and removed from the hollow space 32. The slime and cement milk could be easily removed by simple operation.

  Next, embodiments of the present invention will be described below with reference to the accompanying drawings.

1. Summary of the Invention The foundation pile construction method of the present invention further includes the following work steps in the work process of the known embedded pile method using a hollow ready-made pile.

(1) Slime and / or cement milk removal process In this process, in the process of the embedded pile method using a hollow ready-made pile, it exists in the hollow space 32 of the hollow pile 30 built in the excavation hole 40. The slime in the hollow space 32 from the pile head 31 to an arbitrary depth corresponding to the desired strength improvement effect on the entire pile when the slime or cement milk is still in a liquid or gel state before curing. And / or remove the cement milk.

  If the pile head 31 is provided at a predetermined depth in the excavation hole 40 prior to the removal of the slime and / or cement milk, excavation from the pile head 31 to the upper end of the excavation hole 40 is performed. By inserting a cylindrical tubular sheet pile 60 into the hole 40 and working through the space surrounded by the tubular sheet pile 60, the inner wall of the excavation hole 40 is protected and the hollow space 32 of the hollow pile 30 is protected. You may make it prevent invasion of earth and sand and muddy water.

(2) Arrangement step of pile inner lid body In this step, the pile inner lid body 74 is arranged at the bottom of the hollow space 32 from which the slime and / or cement milk has been removed.

(3-1) Filling of ready-mixed concrete In this process, ready-mixed concrete is filled onto the pile inner lid 74.

  After filling the ready-mixed concrete, the pile head 31 may be covered with a pile inner lid 74 to prevent intrusion of earth and sand or muddy water into the hollow space 32 of the hollow pile 30, When the cylindrical sheet pile 60 is used, the lower end opening of the cylindrical sheet pile 60 is covered with the lower lid 68 and the upper end opening is covered with the upper lid 67, and earth and sand or muddy water is placed in the hollow space 32 of the hollow pile 30. Etc. may be configured to protect the pile head 31 of the hollow pile 30.

(3-2) Inserting Core Pile In another embodiment of the present invention, instead of the step (3-1), in the hollow space 32 of the hollow pile 30, a mortar is placed on the inner lid 74 of the pile. Fill.

  Next, a core pile having the same outer diameter as the hollow pile described later, having an outer diameter smaller than the inner diameter of the hollow pile 30 and having a length that allows the top end of the hollow pile top to substantially reach the top of the hollow pile on the pile inner lid 74. It is inserted into the hollow space 32.

2. As described above, the foundation pile construction method of the present invention is based on a known embedded pile method using a hollow ready-made pile. Furthermore, if the pile head 31 can be strengthened by including it, and the state where the cement milk is filled in the hollow space 32 of the hollow pile 30 built in the excavation hole 40 can occur, Any known embedded pile method may be used as a basis.

  For example, when the hollow pile 30 is built after filling the excavation hole 40 with cement milk, the hollow pile 30 is built before filling the cement milk, and the cement milk is passed through the hollow space 32 of the hollow pile 30, for example. The foundation pile construction method of the present invention can be applied regardless of the construction procedure of the embedded pile construction method used as a foundation, etc., and the hollow pile 30 to be used is also PC pile, PHC pile, etc. Any material may be used, such as concrete piles, metal piles such as steel pipes, and other steel pipe concrete piles such as SC piles.

3. Equipment to be used In the construction method of the foundation pile of the present invention, in addition to the equipment (for example, excavator such as an earth auger, etc.) used in the known embedded pile construction method as the foundation, each process described above is added. Use the equipment to realize. In the present embodiment, the following devices are used as an example.

(1) Removal container The removal container 10 is used to remove slime and / or cement milk from the hollow space 32 of the hollow pile 30 in the above-described slime and / or cement milk removal step. The container 10 has a removal container main body 11 (11a, 11b, 11c) which is inserted into the hollow space 32 of the hollow pile 30 from the pile head 31 and formed to cover the space.

  1-3, the removal container main body 11 is formed in a cylindrical shape having a diameter that can be inserted into the hollow space 32 of the hollow pile 30, but the removal container 10 of the removal container 10 is shown here. The diameter or shape of the main body 11 is not limited to a cylindrical shape as shown in the figure, and can be formed in various shapes, for example, corresponding to the shape of a ready-made pile to be used.

  In the removal container main body 11 of the removal container 10, a recovery space 12 for recovering the slime and / or cement milk to be removed is formed as shown in FIG. , An opening 13 for introducing slime and / or cement milk into the recovery space 12 in the removal container body 11 is formed, and a cover plate 14 is provided to cover the opening 13 from the inside (see FIG. 2 and 3).

  The opening 13 is located at any position where liquid or gel-like slime and / or cement milk can be introduced when the removal container 10 is inserted into the hollow space 32 of the pile head 31 from the bottom side. In this embodiment, the opening is formed on the bottom surface of the removal container body 11 formed in a bottomed cylindrical shape.

  The lid plate 14 has a size capable of closing the opening 13 and is swingably fixed in the recovery space 12 so that the opening 13 can be opened by the inflow pressure of the unnecessary material. In the illustrated embodiment, one end is fixed to the bottom plate of the removal container main body 11 by a hinge 15, and when the opening 13 is closed, the cover plate 14 covers the opening 13 from the inside. In addition to closing, it swings about the hinge 15 as a fulcrum, so that it rises on the bottom plate and opens the opening 13.

  In the illustrated embodiment, the cover plate 14 has a single-open configuration, but for example, two cover plates may be attached so as to be a so-called “double door”, and as described above, Any configuration may be used as long as the opening 13 can be closed and the opening 13 can be opened by the inflow pressure of an unnecessary substance flowing into the recovery space 12.

  In FIG. 2, S is a stopper, and when the cover plate 14 is opened, the swing range of the cover plate 14 is restricted so that the cover plate 14 has an opening angle of less than 90 degrees.

  For example, in the embodiment shown in FIG. 2, when the opening angle of the lid plate 14 exceeds 90 degrees and the tip (free end) swings until it contacts the inner wall of the removal container body 11, the lid plate 14 is stabilized at this position. However, as shown in FIG. 2, the opening angle of the cover plate 14 is less than 90 degrees by the stopper S (85 degrees in this embodiment). ), The weight of the slime and / or cement milk when the cover plate 14 is removed by its own weight when released from the pressure at the time of introduction of the slime and / or cement milk or from the hollow space of the hollow pile. Thus, the opening 13 is reliably tilted to close the opening 13.

  When the slime and / or cement milk is introduced into the removal container main body 11, the collection space 12 in the removal container main body 11 is in the collection space 12 according to the amount of the slime and / or cement milk introduced. The upper part is opened so that air can be discharged. In this embodiment, the removal container body 11 is formed of a cylindrical body, and the upper end of the removal container body 11 that is the cylindrical body is opened. is doing.

  A connecting portion 19 for enabling the removal container 10 to be suspended is provided at the upper end of the removal container main body 11 configured as described above.

  In the present embodiment, a support member 21 is provided between the inner periphery of the removal container body 11 in the upper end opening of the removal container body 11 which is a cylindrical body. 19 is provided.

  In the embodiment of FIGS. 1 and 2, a first H-shaped steel 21 a that spans the inner periphery of the upper opening of the removal container main body 11 in the diameter direction, and a center in the length direction of the first H-shaped steel 21 a. The support member 21 is formed by the second and third H-shaped steels 21b and 21c spanned between the portion and the inner periphery of the removal container body 11 so as to be orthogonal to each other in plan view (see FIG. 1). The upper end of the removal container main body 11 can be reinforced and the connecting portion 19 can be attached without closing the upper end opening of the removal container main body 11.

  The above-described connecting portion 19 is provided at the central portion of the support member 21 configured as described above. In this embodiment, the connecting portion 19 is used as a joint portion of a screw rod of an excavator. Hexagonal column joint (male) is fixed.

  By providing the connecting portion 19 in this way, the connecting portion 19 is inserted into the joint (female) provided at the tip of the screw rod, and the pin hole provided in the joint (female) provided on the screw rod The removal container 10 can be easily attached to the tip of the screw rod by inserting a locking pin into the pin hole provided in the connector 19 together.

  In addition, the structure of the removal container 10 is not limited to the structure demonstrated with reference to FIGS. 1-3, A various change is possible.

(2) Discharge Auxiliary Means 50 in FIGS. 4 to 7 is a discharge assist that can easily discharge slime and cement milk extracted by the above-described removal container 10 when used in combination with the removal container 10. Means 50.

  The discharge assisting means 50 includes a base 55 on which the removal container 10 can be placed, and an engaging projection 56 erected on the base 55, and the removal container 10 is attached to the base of the discharge assisting means 50. When placed on the table 55, the engaging projection 56 pushes up the cover plate 14 that covers the opening 13 provided at the bottom of the removal container 10, thereby discharging the unnecessary material stored in the removal container 10. Do.

  When providing means for facilitating the discharge of the recovered slime and / or cement milk in the removal container 10 itself, it is not necessary to separately provide such a discharge auxiliary means. When the removal container is placed on the floor surface or the ground by, for example, providing an engaging protrusion that protrudes downward when the opening is covered, the lower end of the engaging protrusion is placed on the ground plate or the floor surface. The cover plate 14 may be configured to be opened by contact with the cover plate 14.

  In the illustrated embodiment, the discharge assisting means 50 is composed of an H-shaped steel, a square pipe, or the like 3 between the upper surfaces of the leg portions 51, 51 formed by arranging two H-shaped steels, square pipes, etc. in parallel. The horizontal members 52, 53, 54 are installed to form the base 55, and the removal container 10 can be placed on the horizontal members 52, 53, 54 of the base 55. The space formed between the horizontal members 53 and 54 in the illustrated example secures a discharge space for unnecessary materials.

  The discharge assisting means 50 is for restricting or guiding the placement position of the removal container 10 with respect to the discharge assisting means 50 so that the engaging projection 56 can accurately push up the lid plate 14 here. In the present embodiment, four restricting pieces 57a to 57d protrude from the upper surface of the base 55, and the bottom portion of the removal container 10 is in a space surrounded by the restricting pieces 57a to 57d. Are arranged (see FIGS. 6 and 7).

  In addition, the member shown with the code | symbol 58 provided in the said base 55 is a suspension ring, and in this embodiment, this suspension ring 58 is attached to the both ends of the length direction of the said leg parts 51 and 51. As shown in FIG. By fixing each to the upper surface, it is possible to attach a wire or the like so that it can be easily suspended and moved.

(3) Cylindrical sheet pile FIGS. 8A and 8B show that the height of the excavation hole 40 from the pile head 31 to the ground surface is as high as 2 m or more, or the ground of the excavation hole 40 is soft. In this case, regarding the cylindrical sheet pile 60 suitable for construction such as when springing from the excavation hole ground of the pile head 31, the above-described slime and / or cement milk removal process is performed on the ready-mixed or hardened raw concrete or mortar. In all the processes up to filling, after being inserted into the excavation hole 40, and after filling the ready-mixed concrete, the top and bottom openings of the cylindrical sheet pile 60 are covered so that the earth and sand from the pile head 31 of the hollow pile 30 can be covered. In addition to preventing the intrusion of muddy water and the like, the pile head 31 is protected from damage and the like.

  9 to 10, the cylindrical sheet pile 60 has a cylindrical shape having an outer diameter smaller than the inner periphery of the excavation hole 40, and has a L-shaped cross section between upper and lower frame bodies 61 and 62. The holding rod 63 is inserted, the screw portions at the upper and lower protruding ends are fixed to the frame bodies 61 and 62 with nuts or the like, the upper and lower frame bodies 61 and 62 are connected, and the guide pieces provided on the upper and lower frame bodies in opposite directions, respectively 64, 64 is a cylinder 70 such as a metal cylinder or a void tube fitted and fixed. Reference numeral 65 denotes an insertion portion for guiding or holding the insertion of the hollow pile 30 into the pile head 31 protruding from the bottom edge of the lower frame 62 having an outer diameter that fits the inner periphery of the pile head 31 of the hollow pile 30. It is an annular plate-like member for the purpose. In the embodiment of FIG. 8, the void pipe 70 is vertically stacked to increase the overall length of the cylindrical sheet pile 60. For this reason, a holding rod 63 is connected to the upper and lower sides via a joint 71, and the holding rod 63 is annularly arranged at an appropriate position. The upper and lower void pipes 70 are supported above and below the projecting portion 73. Accordingly, the overall height or total length of the tubular sheet pile 60 can be arbitrarily set corresponding to the pile head 31.

  The holding rod 63 is provided at a position where the circumference is equally divided on the inner periphery of the cylindrical body 70 and imparts rigidity to the cylindrical sheet pile 60 against the earth pressure from the outside.

  The above-mentioned cylindrical sheet pile 60 is covered with raw and concrete upper and lower lids 67, 68, for example, which are detachable after filling with ready-mixed concrete as a filling / hardening material, and rooting work is performed. After performing, after curing, the cylindrical sheet pile 60 is carried out and removed together with the upper and lower lids 67, 68. As a result, it is possible to prevent the pile head from being damaged by the root cutting operation.

  Of course, the core pile remains in the hollow pile 30.

  In addition, when the height of the excavation hole 40 from the pile head 31 to the ground surface is relatively low, or when the ground of the excavation hole 40 is not soft, there is a risk of springing from the excavation hole ground of the pile head 31 For construction such as when there is no pipe, it is not necessary to use the sheet pile 60, but after filling with ready-mixed concrete, a lid (pile head) not shown is placed on the pile head, You may make it backfill to the ground surface or perform root cutting without backfilling, and then remove the pile skull.

(4) Pile inner lid body As described above, the pile inner lid body 74 appeared as a space by removing slime and / or cement milk from the pile head 31 of the hollow pile 30 to an arbitrary depth. It is placed on the bottom of the hollow space 32 and has a disk shape that is sized to be inserted into the hollow pile 30.

  The pile inner lid 74 is disposed on the bottom of the hollow space 32 and thus on the surface of the cement milk that remains unremoved, and a filling / hardening material is placed on the pile inner lid 74 as will be described later. After the filling, the pile inner lid body 74 is embedded at a predetermined position in the hollow pile 30.

  The pile inner cover 74 is formed by directly filling ready-mixed concrete with a liquid or gel-like cement milk before hardening into a hollow pile 30. The pile inner lid 74 is disposed in the hollow pile 30 in advance, and is provided in order to solve the problem that the pile head 31 can not be retained at the desired position of the pile head 31. By filling the cover 74 with ready-mixed concrete, the ready-mixed concrete can be hardened at a predetermined position near the pile head 31.

  Therefore, the material and shape of the inner lid 74 of the pile is not particularly limited as long as it can prevent the filled ready-mixed concrete from sinking into the cement milk. can do.

  As an example, in this embodiment, a plate made of metal such as steel formed in a disk shape to be fitted in a hollow pile is used as the above-described inner lid body.

4). Construction method of foundation pile Next, the construction method of the pile foundation of the present invention using each device described above will be described below.

(A) Processing stage by the known embedded pile method Fig. 11 (A) is a foundation pile in the middle of construction by the known embedded pile method using a hollow ready-made pile. In the hollow pile 30 contained, there is liquid or gel cement milk before hardening.

  In the illustrated embodiment, the pile head 31 of the hollow pile 30 is provided at a position lower than the upper end (the ground surface) of the excavation hole 40, but exists beyond the pile head 31 of the hollow pile 30. Sediment is the part that is removed by root cutting when the foundation of the structure built on the hollow pile 30 is formed.

(B) Attachment of cylindrical sheet pile and removal of slime and / or cement milk FIG. 11 (B) is from inside the hollow space 32 of the hollow pile 30 in the state of FIG. 11 (A) described above in the construction process of the pile foundation. This is a step of removing slime and / or cement milk using the removal container 10 described above.

  In the present embodiment, when performing the removal by the removal container 10, the inner circumference from the pile head 31 of the hollow pile 30 to the upper end of the excavation hole 40 is formed to have a smaller diameter than the inner diameter of the excavation hole 40. While inserting the above-mentioned cylindrical sheet pile 60, it was mounted so that the insertion part 65 provided in the lower end of this cylindrical sheet pile 60 might be inserted in the hollow space 32 in the pile head part 31 of the hollow pile 30.

  The cylindrical sheet pile 60 protects the inner wall of the excavation hole 40, and earth and sand generated by the collapse of the inner wall of the excavation hole 40, mud water associated with spring water in the excavation hole 40, etc. 32 is prevented from entering.

  In the embodiment shown in FIG. 11 (B), the removal container 10 and the cylindrical sheet pile 60 are inserted into the excavation hole 40 at the same time. However, the cylindrical sheet pile 60 is inserted into the excavation hole 40 in advance. The removal container 10 is put into the hollow space 32 of the hollow pile 30 through the space surrounded by the cylindrical sheet pile 60 in a state where the inner wall protection of the excavation hole 40 and the infiltration of earth and sand and spring water into the hollow pile 30 are prevented. It may be inserted, and can effectively protect the inner wall of the excavation hole 40, prevent infiltration of earth and sand and spring water into the hollow pile 30, and remove slime and / or cement milk in the hollow pile 30 If so, the attachment procedure of the tubular sheet pile 60 is not limited to the illustrated embodiment.

  In this way, the slime and cement milk in the hollow pile 30 are removed using the removal container 10 with the cylindrical sheet pile 60 inserted into the excavation hole 40.

  As described above, the removal container 10 has a recovery space 12 for recovering liquid or gel-like slime and / or cement milk in the cylindrical main body 11 in the present embodiment, and this recovery space. 12 has an opening 13 that opens downward, and is provided with an openable / closable lid plate 14 that covers the opening 13. As an example, as shown in FIG. When the removal container 10 is attached to the tip of the screw rod of the excavator and inserted into the hollow space 32 of the hollow pile 30, the opening 13 of the removal container 10 is opened by the pressure of slime and / or cement milk in the hollow space 32. The closed lid 14 is opened, whereby slime and / or cement milk flows into the recovery space 12 of the removal container 10.

  When the inflow of slime and / or cement milk is completed in the removal container 10 in this way, the cover plate 14 that has opened the opening 13 by the inflow of this slime and / or cement milk closes the opening 13 by its own weight.

  And if the removal container 10 is extracted from the hollow space 32 of the hollow pile 30, the cover plate 14 will completely close the opening 13 by the weight of the slime and / or cement milk introduced into the recovery space 12 of the removal container 10, The slime and / or cement milk confined in the collection space is removed from the hollow space 32 of the hollow pile 30 together with the removal container 10 and removed.

  Such slime and / or cement milk removal corresponds to the length (depth) from the pile head 31 of the hollow pile 30 corresponding to the desired strength improvement effect on the entire pile. If the required amount of slime and / or cement milk cannot be removed by a single insertion of the removal container 10, this operation is repeated until the required depth of slime and / or cement milk is reached. Perform removal.

  In addition, in the above-described embodiment described with reference to FIG. 11 (B), the cement milk in the hollow pile was removed while the cylindrical sheet pile 60 was inserted into the excavation hole. The above-mentioned cylindrical sheet pile, for example, may be omitted if the depth from the pile head to the upper end of the excavation hole is 2 m or less and there is no spring water or the like in the excavation hole.

(C) Discharge of slime and / or cement milk from removal container The slime and / or cement milk removed by the removal container 10 is extracted out of the excavation hole 40 together with the removal container 10, and is shown in FIG. As shown, when the above-described discharge assisting means 50 is provided, it is placed on the discharge assisting means 50 and discharged.

(D) Arrangement of Pile Inner Body After removing a predetermined amount of slime and / or cement milk in the hollow pile 30 in this way, the slime and / or cement milk is placed in the pile head 31 of the hollow pile 30. The hollow space 32 from which is removed appears.

  On the bottom of the hollow space 32, that is, on the liquid level of cement milk that remains in the hollow pile 30 without being removed, as shown in FIG. 11 (D), a pile inner lid 74 formed in a disk shape. For example, by pushing in with a push rod or the like.

  By the arrangement of the pile inner lid 74, a floor surface for filling the ready-mixed concrete described later is formed, and the filled ready-mixed concrete is prevented from sinking into the cement milk.

(E-1) Filling of ready-mixed concrete FIG.11 (E) is a process of filling ready-mixed concrete on the pile inner cover board 74 arrange | positioned in the hollow pile 30 as mentioned above.

  In this embodiment, the filling of the ready-mixed concrete is performed by inserting a trayy pipe into the hollow pile 30, and the pile head is gradually pulled upward while filling the ready-mixed concrete from the lower end of the trayy pipe. The concrete is filled up to a predetermined position of the part 31.

(E-2) Insertion of core piles Insertion of core piles is carried out by filling the above-mentioned various mortars on the pile inner lid 74 in place of filling the ready-mixed concrete in the step (E-1).

  Although illustration is omitted, in another embodiment of the present invention, mortar is filled on the inner lid body 74 in the hollow space 32 of the hollow pile 30. This mortar is selected from high strength, no shrinkage, and resin mortar, and is injected and filled in an amount equal to or larger than the volume of the core pile to be inserted into the hollow space 32 later.

  Next, as with the hollow pile described later, it is made of PC, PHC, RC, steel pipe, steel tube wound concrete, has an outer diameter smaller than the inner diameter of the hollow pile 30, and the upper end of the top of the hollow pile on the pile inner lid 74 is A core pile having a length that is substantially reached is inserted into the hollow space 32.

  By inserting the core pile, the mortar overflows from the top of the core pile and fills the gap between the inner periphery of the hollow pile 30 and the outer periphery of the core pile. Thereby, consolidation of the hollow pile 30 and a core pile can be achieved.

(F) Covering the pile head In this way, when the filling of the ready-mixed concrete or the insertion of the core pile is completed, the lid that covers the pile head 31 of the hollow pile 30 is, for example, pushed The pile head 31 is covered by pushing (FIG. 11 (F)), and earth and sand, muddy water, and the like are prevented from entering the hollow space 32 of the hollow pile 30.

  In this embodiment in which the lid covering the pile head 31 of the hollow pile 30 performs the above operations with the cylindrical sheet pile 60 inserted into the excavation hole 40, the lower frame body of the cylindrical sheet pile The opening formed in 62 may be closed by the lower lid 68.

  As described above, when the above operations are performed without using the above-mentioned cylindrical sheet pile 60, such as when the distance from the pile head 31 to the upper end (the ground surface) of the excavation hole 40 is 2 m or less. The pile head 31 of the hollow pile 30 can be directly covered with an unillustrated pile head body to replace the illustrated process.

(G) Covering the upper end of the cylindrical sheet pile In this way, after covering the pile head 31 of the hollow pile 30, the opening formed in the upper frame 61 of the cylindrical sheet pile 60 is further opened by the upper cover 67. In this state, the cylindrical sheet pile 60 is placed on the pile head 31 of the hollow pile 30 until the root cutting is completed.

  Thus, the pile head 31 of the hollow pile 30 is protected by the lower lid body 68, the upper lid body 67, and the cylindrical sheet pile 60, and earth and sand, muddy water, etc. can enter the hollow space 32 of the hollow pile 30. In addition to being prevented, since the space above the pile head 31 is occupied by the cylindrical sheet pile 60, this cylindrical sheet pile 60 acts as a kind of protector for the pile head 31 and, for example, back-hoe When pruning using an excavator, etc., the pile head 31 can be protected from contact with the backhoe bucket, etc., and damage to the pile head due to such contact can be prevented. .

(H) Removal of Pipe Sheet Pile As described above, when the cutting of the foundation forming position is completed, the above-described pipe sheet pile 60 is removed from the pile head 31 together with the upper and lower lid bodies 67 and 68.

  In this way, the pile head 31 of the hollow pile 30 appears on the bottom of the root cutting, and the foundation of the upper structure can be constructed on the pile head 31.

(I) Others After the necessary treatments such as consolidation, split chestnut laying, installation of concrete panels, bar arrangements, etc., the concrete is laid in the deforestation formed as described above. The foundation of the structure is formed on the foundation pile formed by the hollow pile 30 described above.

  If necessary, a reinforcing bar for joining is attached to the pile head 31 of the hollow pile 30, and the reinforcing bar for joining is joined to the reinforcing bar of the foundation formed on the upper part, embedded in the foundation, etc. The pile head may be fixed to the foundation.

  The foundation pile formed in this way has strength by removing slime that causes a decrease in strength and cement milk containing impurities such as slime from the hollow space 32 in the pile head 31 as described above. Not only the pile head 31 of the hollow pile 30 but also the pile because it is filled with ready-mixed concrete with a relatively high strength after hardening instead of the removed slime and cement milk. The whole will be strengthened.

  As a result, without increasing the diameter of the pile head 31 or without reinforcing a steel pipe around the pile head 31, the pile is constructed on the basis of a known embedded pile method using a hollow ready-made pile. The head was easily strengthened.

The top view which shows one Embodiment of a removal container. II-II sectional view taken on the line of FIG. III-III sectional view taken on the line of FIG. The front view which shows one Embodiment of a discharge assistance means. The top view which shows one Embodiment of a discharge assistance means. The front view of the state which mounted the removal container on the discharge assistance means. The top view of the state which mounted the removal container on the discharge assistance means. (A) is a general view of the tubular sheet pile 60, (B) is a partial sectional view. (A), (B) shows the up-and-down frame of the cylindrical sheet pile 60, respectively. (A) is a plan view of the upper frame 61, and (B) is a bottom view of the lower frame. It is a figure which shows the attachment structure of the upper-and-lower cover bodies 67 and 68 and the upper cover body 67, The same figure (A) is a bottom view of the upper cover body 67, The same figure (B) is to the cylinder sheet pile 60 of the upper cover body 67 The partial figure which shows the attachment state of (1), the figure (C) is a top view of a lower cover body. It is process drawing which shows the construction method of the foundation pile of this invention, (A) is the state with which cement milk was filled in the hollow pile, (B) is the removal process of slime and / or cement milk, (C) is discharge | emission. Discharge process by auxiliary means, (D) is the process of placing the lid inside the pile, (E) is the process of filling the ready-mixed concrete, (F) is the process of covering the pile head with the pile head, and (G) is the cylinder sheet pile Covering process of upper end opening, (H) is a process of removing the cylindrical sheet pile after root cutting.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Removal container 11 Removal container main body 12 Collection | recovery space 13 Opening 14 Cover plate 15 Hinge 19 Connection part (joint)
DESCRIPTION OF SYMBOLS 21 Support material 21a 1st support material 21b 2nd support material 21c 3rd support material 30 Hollow pile 31 Pile head 32 Hollow space 40 Excavation hole 50 Discharge auxiliary means 51 Leg parts 52, 53, 54 Horizontal member 55 Base 56 Engagement projection 57a-57d Restriction piece 58 Hanging ring 60 Cylindrical sheet pile 61 Upper frame body 62 Lower frame body 63 Holding rod 64,64 Guide piece 65 Insertion part 67 Upper lid body 68 Lower lid body 70 Cylindrical body 71 Joint 72 Supporting piece 73 Projecting part 74 Pile inner lid S Stopper

Claims (4)

In the embedded pile construction method using hollow ready-made piles,
When slime or cement milk existing in the hollow space of the hollow pile built in the excavation hole is in liquid or gel form, a removal container is inserted from the pile head to an arbitrary depth, and the inside of the hollow space A step of containing a slime and / or cement milk and discharging it to the outside;
Placing a lid on the bottom of the hollow space from which the slime and / or cement milk has been removed;
Look including the step of filling the filling and curing material on the cover,
The pile head of the hollow pile is arranged at a predetermined depth in the excavation hole, and a cylindrical tubular sheet pile is inserted into the excavation hole from the pile head to the upper end of the excavation hole. Removing the slime and / or cement milk through the space surrounded by the cylindrical sheet pile, placing the lid on the bottom of the hollow space, and filling the filling / curing material,
After filling with the filling / curing material, the lower end opening of the cylindrical sheet pile is covered with a lower lid, and the upper end opening of the cylindrical sheet pile is covered with an upper lid .   2. The foundation pile construction method according to claim 1, further comprising a step of filling ready-mixed concrete as a filling / hardening material on the lid.   The lid in the hollow space is filled with mortar as a filling / hardening material, the hollow pile has an outer diameter smaller than the inner diameter of the hollow pile, and the upper end of the hollow pile has a top end substantially reaching the top. A method for constructing a foundation pile according to claim 1, wherein a core pile is inserted. A space for containing the slime and / or cement milk to be removed is formed so as to be covered, and a recovery space for introducing the slime and / or cement milk is provided therein, and an opening for opening the recovery space on the bottom side is provided. Preparing a removal container provided with a removal container body provided, and an openable / closable lid plate that covers the opening of the removal container body;
Inserting the removal container into the hollow space of the hollow pile from the bottom of the removal container;
Opening the lid plate and introducing the slime and / or cement milk into the recovery space;
And tegmental said opening in said cover plate, by the removal container withdrawn from the hollow space, one of claims 1 to 3, characterized in that the removal of slime and / or cement milk of the hollow space The construction method of the foundation pile of 1 item | term.

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