JP5904585B2 - Pile concrete placement method - Google Patents

Description

  The present invention relates to a pile concrete placing method. Specifically, the present invention relates to a method for placing pile concrete of a pile into which a structural pillar is driven by a reverse driving method.

Conventionally, in order to shorten the construction period, there is a case where a building is constructed by a reverse driving method.
In this case, for example, a pile hole is excavated in the ground, a reinforcing steel basket is inserted into the pile hole, and pile concrete is placed. Is integrated into the pile. Then, while excavating the ground, the basement floor is constructed in order downward, and at the same time, the ground floor steel frame is connected to the upper end portion of the structural pillar, and the ground floor is constructed in order upward.
As a result, the construction of the underground floor and the construction of the ground floor can be carried out simultaneously, so that the construction period can be shortened.

  By the way, there are two methods for placing pile concrete: the so-called construction pillar pre-decoration method in which pile concrete is placed after the construction of the construction pillar, and the so-called construction construction in which construction pillars are built after placing the pile concrete. There is a post-post construction method. Of these, according to the construction method of the timber pillar, pile concrete is placed after the construction of the timber pillar is hardened with a jack or the like. Since there is no need to do this, the structural pillar can be built with high accuracy (see Patent Document 1).

Japanese Patent No. 3878772

  By the way, in the above-mentioned method, the treble pipe is arranged along the side face of the true pillar and the pile concrete is placed through the tremy pipe. Therefore, there has been a problem that it is difficult to ensure the vertical accuracy of the structural pillar because the lower step of the structural pillar is pushed in one direction by the ready-mixed concrete discharged from the tip of the tremy tube.

  In particular, when the pile diameter is small or the reinforcement of the pile body is dense, it is necessary to use one tremy pipe.

  In addition, when the structural pillar is tilted, it may be possible to correct the vertical accuracy of the structural pillar with an underwater jack or the like, but in reality, the ready-mixed concrete resists the movement of the lower section of the structural pillar. It was difficult to correct.

  An object of this invention is to provide the pile concrete placement method which can ensure the vertical accuracy of a structure pillar as much as possible when pile concrete is cast after building a structure pillar.

  The pile concrete placement method according to claim 1 is a pile concrete placement method by a reverse casting method, and includes a lower step portion (for example, a lower step portion 10 described later) and an upper end of the lower step portion. An upper step portion (for example, an upper step portion 20 described later) joined to the lower step portion and an annular guide member (for example, a later-described guide member described later) provided on the lower step portion and surrounding the lower step portion. 40, 40A, 40B) are prepared, and the post is inserted into a pile hole (eg, a post hole 3 described below). In addition, a step of extending a road thread (for example, a road thread 50 described later) upward from the lower end of the lower step portion of the stem column and passing the inside of the guide member to be exposed to the ground from the pile hole (for example, described later) Step S2) and the concrete along the road A step of inserting a hose for placing (for example, a tremy tube 60 described later) into the pile hole and guiding the concrete placing hose through the inside of the guide member to the lower end of the structural pillar (for example, step S3 described later) ) And a step of placing pile concrete through the inside of the concrete placing hose (for example, step S4 described later).

According to this invention, when the concrete placement hose is inserted into the pile hole along the road line from the ground, the concrete placement hose passes through the inside of the guide member, To the bottom. At this time, the concrete placing hose is guided toward the column core of the structural pillar by the guide member.
Therefore, when placing pile concrete, this pile concrete is discharged in the vicinity of the pillar core of the construction pillar, so that the construction pillar can be prevented from being pushed in one direction by the pile concrete. Vertical accuracy can be ensured as much as possible.

  The pile concrete placing method according to claim 2, wherein the concrete placing hose includes a plurality of straight steel pipe hoses (for example, a steel pipe hose 61 described later) and a plurality of flexible rubber hoses ( For example, a rubber hose 62) described later is connected by a connecting member (for example, a connecting member 63 described later).

  According to the present invention, the concrete placing hose is configured by appropriately combining the steel pipe hose and the rubber hose, so that the concrete placing hose can be bent by the guiding member and reliably guided toward the column core.

  The pile concrete placing method according to claim 3 is characterized in that the guide member (for example, guide members 40 and 40A described later) is an annular flat steel material in an approximately horizontal plane or an annular flat surface that expands outward as it goes upward. Steel materials (for example, flat steel materials 41 and 41A described later) and annular flat steel materials (for example, flat steel materials 42 and 42A described later) that are attached to the inner edge of the flat steel material and expand outward as it goes downward. It is characterized by that.

  According to the present invention, since the lower side of the guide member is an annular flat steel material that expands outward as it goes downward, when the concrete placement hose is pulled out from the inside of the guide member, Even if the inner surface of the guide member slides, the connecting member of the concrete placement hose can be prevented from being caught by the guide member, and the concrete placement hose can be pulled out smoothly.

  In addition, since the upper side of the guide member is an annular flat steel material that expands outward as it goes upward, when the concrete placement hose is inserted inside the guide member, the concrete placement hose is placed inside the guide member. Even if the surface is slid, the connecting member of the concrete placing hose can be prevented from being caught by the guide member, and the concrete placing hose can be inserted smoothly.

In the method for placing pile concrete according to the present invention, the guide member (for example, a guide member 40B described later) is a steel material having a circular and circular longitudinal section, and a longitudinal section radius (for example, described later) of the guide member. The radius r) is preferably larger than the projecting dimension (for example, a predetermined dimension d described later) of the connecting member from the concrete placing hose.

  According to this invention, the longitudinal cross-sectional radius of the guide member is made larger than the protruding dimension of the connecting member from the hose. Therefore, when inserting the concrete placement hose inside the guide member, or when pulling out the concrete placement hose from the inside of the guide member, the concrete placement pipe slides on the inside surface of the guide member. However, at this time, the connecting member of the concrete placing hose can be prevented from being caught by the guide member, and the concrete placing hose can be inserted and pulled out smoothly.

  According to the present invention, when the concrete placement hose is inserted into the pile hole along the road line from the ground, the concrete placement hose passes through the inside of the guide member, To the bottom. At this time, the concrete placing hose is guided toward the column core of the structural pillar by the guide member. Therefore, when placing pile concrete, this pile concrete is discharged in the vicinity of the pillar core of the construction pillar, so that the construction pillar can be prevented from being pushed in one direction by the pile concrete. Vertical accuracy can be ensured as much as possible.

It is sectional drawing of a built-up pillar and a pile to which the placement method of pile concrete concerning a 1st embodiment of the present invention is applied. It is an enlarged side view of the vicinity of the joint portion of the true pillar according to the embodiment. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a flowchart of the procedure which drives a built-up pillar concerning the embodiment into a pile. It is an expanded sectional view of the induction member vicinity of the construction pillar to which the placement method of pile concrete concerning a 2nd embodiment of the present invention is applied. It is an expanded sectional view of the induction member vicinity of the construction pillar to which the placing method of pile concrete concerning a 3rd embodiment of the present invention is applied.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same constituent elements are denoted by the same reference numerals, and the description thereof is omitted or simplified.
[First Embodiment]
FIG. 1 is a cross-sectional view of a built-up column and a pile to which the method for placing pile concrete according to the first embodiment of the present invention is applied.
The structural pillar 1 is used for the reverse driving method and is driven into a cast-in-place pile 2 formed inside the pile hole 3. The structural pillar 1 includes a lower step portion 10 that extends in the vertical direction and is inserted into the cast-in-place pile 2, an upper step portion 20 that extends upward from the upper end of the lower step portion 10, and a lower step portion 10 and an upper step portion 20 And a joint portion 30 provided between the two.

  The structural pillar 1 extends from the cast-in-place pile 2 to the ground surface (1FL) level, and the joint 30 of the structural pillar 1 is located in the mat slab of the foundation of the underground frame.

FIG. 2 is an enlarged side view of the vicinity of the joint 30 of the true pillar 1. 3 is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line BB in FIG. These FIGS. 2-4 shows the state before pile concrete placement of the pile 2. FIG.
The lower part 10 is made of a cross H-section steel 11. Specifically, the cross H-section steel 11 includes a web 12 having a cross-shaped cross section and four flanges 13 provided with end portions of the web 12.
The upper stage portion 20 is composed of a rectangular steel pipe 21 having a rectangular frame shape with a closed lower end.

  In the joint portion 30, the cross-shaped cross-shaped web 12 of the cross H-section steel 11 constituting the lower step portion 10 is extended to the inside of the square steel pipe 21 constituting the upper step portion 20. Specifically, the lower end surface of the upper stage portion 20 is closed by a plate material 31 extending in a substantially horizontal direction, and the web 12 is provided above and below the plate material 31.

  On the other hand, the flange 13 of the cross H-section steel 11 constituting the lower step portion 10 is connected to a plate material 31 which is the lower end edge of the square steel pipe 21 constituting the upper step portion 20.

In the lower step portion 10, a stud 14 is welded to the outer surface of the flange 13 of the cross H-shaped steel 11.
At the joint 30, a stud 32 is welded to the outer wall surface of the square steel pipe 21, and a stud (not shown) is also welded to the surface of the web 12 of the cross H-section steel 11 extended to the inside of the square steel pipe 21. .

An annular guide member 40 surrounding the lower step portion 10 is attached at a position from the joint portion 30 of the lower step portion 10 of the structural pillar 1.
Further, the brace 1 includes a road thread 50 that extends upward from the lower end of the lower step portion 10 of the brace 1 and passes through the inside of the guide member 40 to reach the upper end of the brace 1. A pair of treme tubes 60 serving as concrete placing hoses that are guided from the ground to the lower end of the true pillar 1 through the inside of the guide member 40 are provided. The pair of tremy tubes 60 are disposed on opposite sides of the true pillar 1.

As shown in FIG. 4, the guide member 40 includes an annular flat steel material 41 in a substantially horizontal plane, and an annular flat steel material 42 which is welded to the inner edge of the flat steel material 41 and expands outward as it goes downward. Prepare. Specifically, the shape of the flat steel material 42 is the same as the shape of the conical surface from which the upper step portion is cut.
Further, the angle formed by the flat steel material 41 and the flat steel material 42 is θ.

The road thread 50 is, for example, a trolley.
Each tremy pipe 60 is configured by combining a plurality of straight steel pipe hoses 61 made of steel and a plurality of flexible rubber hoses 62. The steel pipe hoses 61, the rubber hoses 62, or the steel pipe hose 61 and the rubber hose 62 are connected by a connecting member 63. The connecting member 63 protrudes from the surfaces of the hoses 61, 62 by a predetermined dimension d.

  The tremy tube 60 extends in the vertical direction along the side surface of the upper step portion 20, but is bent by the guide member 40 in the vicinity of the guide member 40, and the flanges 13 of the cross H-section steel 11 of the lower step portion 10 are connected to each other. It is guided in the vicinity of the column core of the lower step portion 10 through the gap. Therefore, a steel pipe hose 61 having no flexibility is used for the upper part of the tremy tube 60 from the guide member 40, and a flexible rubber hose 62 is used for the part below the vicinity of the guide member 40. Is used.

The procedure for driving the above-mentioned structural pillar 1 into the pile 2 will be described with reference to the flowchart of FIG.
First, the guide member 40 and the road thread 50 are attached to the stem 1 in advance.
In step S <b> 1, a pile hole 3 is formed by excavation from the ground, and a reinforcing steel cage (not shown) is inserted into the pile hole 3.

In step S2, the construction pillar 1 is inserted into the pile hole 3, and the construction of the construction pillar 1 is adjusted by the construction adjustment device. At this time, the road thread 50 extends upward from the lower end of the lower step portion 10 of the stem 1 and passes through the inside of the guide member 40 to be exposed from the pile hole 3 to the ground.
In step S <b> 3, the tremy tube 60 is inserted into the pile hole 3 along the road thread 50, and the tip of the tremy tube 60 is guided through the inside of the guide member 40 to the lower end of the structural pillar 1.

  In step S <b> 4, pile concrete is driven through the inside of the tremy tube 60 while the tremy tube 60 is gradually pulled up to form the pile 2.

According to this embodiment, there are the following effects.
(1) When the tremy tube 60 is inserted into the pile hole 3 along the road thread 50 from the ground, the tremy tube 60 passes through the inside of the guide member 40 and reaches the lower end of the structural pillar 1. At this time, as shown in FIG. 4, the tremy tube 60 is curved by the guide member 40 and guided toward the column center of the structural pillar 1.
Therefore, when pile concrete is placed, this pile concrete is discharged in the vicinity of the column core of the built-up column 1, so that it can be prevented that the built-up column 1 is pushed in one direction by the pile concrete. 1 vertical accuracy can be ensured as much as possible.

  (2) Since the tremy tube 60 is configured by appropriately combining the steel tube hose 61 and the rubber hose 62, the tremy tube 60 can be bent with the guide member 40 and reliably guided toward the column core.

  (3) The lower side of the guide member 40 is an annular flat steel material 42 that expands outward as it goes downward. Therefore, when the tremmy tube 60 is pulled out from the inner side of the guide member 40, the connecting member 63 of the tremy tube 60 is guided even if the tremy tube 60 slides on the inner surface of the guide member 40 as shown by an arrow in FIG. It is possible to prevent the member 40 from being caught and to smoothly perform the operation of pulling out the tremy tube 60.

[Second Embodiment]
FIG. 6 is an enlarged cross-sectional view of the vicinity of the guide member 40A of the structural pillar 1 to which the pile concrete placing method according to the second embodiment of the present invention is applied.
In the present embodiment, the shape of the guide member 40A is different from that of the first embodiment.
That is, the guide member 40A includes an annular flat steel material 41A that expands outward as it goes upward, and an annular flat steel material 42A that is welded to the inner edge of the flat steel material 41A and expands outward as it goes downward.
Specifically, the shape of the flat steel members 41A and 42A is the same as the surface shape of the cone from which the upper portion is cut.
The angle of the flat steel material 41A with respect to the horizontal plane is φ1, and the angle of the flat steel material 42A with respect to the horizontal plane is φ2.

According to this embodiment, in addition to the effects (1) and (2) described above, the following effects can be obtained.
(4) The upper side of the guide member 40A is an annular flat steel material 41A that expands outward as it goes upward. Therefore, when the tremy tube 60 is inserted inside the guide member 40A, even if the tremy tube 60 slides on the inner surface of the guide member 40A, as shown by the arrows in FIG. Is prevented from being caught by the guide member 40A, and the insertion operation of the tremy tube 60 can be performed smoothly.

[Third Embodiment]
FIG. 7 is an enlarged cross-sectional view of the vicinity of the guide member 40B of the structural pillar 1 to which the pile concrete placing method according to the third embodiment of the present invention is applied.
In the present embodiment, the shape of the guide member 40B is different from that of the first embodiment.
That is, the guide member 40B is a steel material having a circular longitudinal section and an annular shape. The longitudinal section radius r of the guide member 40B is larger than the projecting dimension d of the connecting member 63 from the hoses 61 and 62.

According to the present embodiment, in addition to the above-described effect (1), the following effect can be obtained.
(5) The longitudinal section radius r of the guide member 40B is made larger than the projecting dimension d of the connecting member 63 from the hoses 61 and 62. Therefore, when the tremy tube 60 is inserted inside the guide member 40B, or when the tremy tube 60 is pulled out from the inside of the guide member 40B, as shown by the arrows in FIG. At this time, the connecting member 63 of the tremy tube 60 is prevented from being caught by the guide member 40B, and the insertion operation and the extraction operation of the tremy tube 60 can be performed smoothly.

  It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.

DESCRIPTION OF SYMBOLS 1 ... Structural pillar 2 ... Pile 3 ... Pile hole 10 ... Lower step part 11 ... Cross H-section steel 12 ... Web 13 ... Flange 14 ... Stud 20 ... Upper step part 21 ... Square steel pipe 30 ... Joint part 31 ... Plate material 32 ... Stud 40 , 40A, 40B ... Inductive member 41, 41A ... Upper flat steel material 42, 42A ... Lower flat steel material 50 ... Road thread 60 ... Tremy tube (concrete casting hose)
61 ... Steel pipe hose 62 ... Rubber hose 63 ... Connecting member

Claims (3)

It is a pile concrete placing method by the reverse casting method,
A lower step portion having a substantially cross-shaped cross section, an upper step portion having a substantially annular or substantially rectangular frame shape joined to an upper end of the lower step portion, and an annular guide member provided in the lower step portion and surrounding the lower step portion; Make a true pillar with
A step of inserting the stem pillar into the inside of the pile hole, extending a road thread from the lower end of the lower step portion of the stem pillar, passing the inside of the guide member, and exposing the pile hole to the ground; ,
Inserting the concrete placement hose along the road line into the pile hole, and guiding the concrete placement hose through the inside of the guide member to the lower end of the structural pillar;
And a step of placing pile concrete through the inside of the concrete placing hose.   2. The concrete placing hose is configured by connecting a plurality of linear steel pipe hoses and a plurality of flexible rubber hoses using a connecting member. Pile concrete placement method. The guide member is an annular flat steel material in a substantially horizontal plane, or an annular flat steel material that expands outward as it goes upward, and an annular flat steel material that is attached to the inner edge of the flat steel material and expands outward as it goes downward If, pile concrete設方method according to claim 1 or 2, characterized in that it comprises a.

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