JP2003055985A - Connecting method of column to pile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the efficiency of work execution to attain the shortening of the term of construction and the saving of construction cost by dispensing with a chemical injection, and dispensing with a footing construction which was performed by a work near a track and the construction of a temporary earth retaining work. SOLUTION: This connecting method comprises a process for rotationally press-fitting a casing and applying it over a hole wall protective range; a process for drilling the casing as a hole wall protective work and placing concrete in the drilled hole to construct a concrete pile 2; and a process for using the upper end of the casing as an outside steel pipe 30 of socket connecting, building a column 8 in the outside steel pipe, and connecting it to the concrete pile.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining a pillar and a pile. 2. Description of the Related Art As a method for constructing a cast-in-place concrete pile using a boring machine, a drill pile is filled with muddy water to protect the hole wall, and the excavated soil is discharged by circulating the muddy water to form a concrete pile. Construction is being done. The construction method of such cast-in-place concrete piles may loosen the ground because excavation holes are formed in the ground. Therefore, in the case of soft ground, a method of protecting the hole wall by injecting a chemical is used. . FIG. 5 shows an example of such a construction method.
When the cast-in-place concrete pile 2 is constructed by the small reverse circulation method in the vicinity of the existing track 1 of the railway, a chemical solution is injected below the mouth casing 3 to improve the ground, and the improved ground 4 is formed. By excavating above, the collapse of the hole wall is prevented, and the deformation of the support ground of the track 1 is prevented. [0004] In the case of joining a cast-in-place concrete pile constructed in this way with, for example, a bridge station building or a pillar of a free passage in a station yard, as shown in FIG. Is provided, and the anchor frame 6 is embedded therein, and the steel pipe column 7 is joined. In this case, the footing 5 needs a predetermined width in order to secure the pull-out shear strength of the anchor frame 6. [0005] In the conventional method of joining a pillar and a pile as shown in FIG. 6, a chemical solution is injected to construct a cast-in-place concrete pile, which is costly and requires a track. The footing may be deformed, and the footing requires a certain width, and the production cost of the anchor frame is increased. In addition, the excavation work for constructing the footing and the construction of the temporary earth retaining work 7 are required. In such a case, the work is performed by closing the track, which increases costs. The present invention has been made to solve the above-described problems, and eliminates the need for injection of a chemical solution, eliminates the need for footing construction and temporary soil retaining work that were performed during track proximity work, streamlines construction, shortens construction time, and reduces construction costs. The goal is to save money. SUMMARY OF THE INVENTION A method of joining a column and a pile according to the present invention, a step of rotationally press-fitting a casing and constructing the same over a hole wall protection range, and drilling the casing as a hole wall protection work. Then, casting concrete into the drilled hole and constructing a concrete pile, and using the casing as an outer steel pipe of a socket joint, erecting a column in the outer steel pipe and joining the concrete pile. It is characterized by becoming. Embodiments of the present invention will be described below with reference to the drawings. The method for joining a cast-in-place concrete pile and a column according to the present invention uses a casing to protect the hole wall and replace the pile and the column using the casing at the upper end, instead of performing the ground improvement by injecting a chemical solution as in the conventional method. Are joined. FIG. 1 is a diagram for explaining a method of constructing a pile as a hole wall protection work by press-fitting a casing with an excavator. The casing 20 includes a tip casing 21, an intermediate casing 22, and a joint member 23, all of which are manufactured using a steel pipe as a main material, and a drilling blade or a composite (not shown) is provided at a tip portion of the tip casing 21. A socket portion (not shown) for connecting the front end casing 21 and another intermediate casing is integrally provided at a front end portion of the casing, and a joint member 23 is provided on a flange for connecting to the excavator 10 and around the same. Having a reinforcing rib (not shown), a tip casing, an intermediate casing,
Although not shown, a coupling member for coupling with each other, and a projection and a notch for restraining relative rotation of each other are formed in the joint members at corresponding positions. When drilling, first, the excavator 10 is installed,
The tip casing 21 is connected thereto via a joint member 23, and the casing 20 is rotationally pressed into the ground by the excavator 10. After rotationally press-fitting substantially the entire length of the distal casing 21, an intermediate casing 22 is added between the distal casing 21 and the joint member 23, and further rotationally press-fitted. After the required number of intermediate casings 22 are added and the casing 20 is installed over the hole wall protection range H, the connection between the uppermost intermediate casing 22 and the joint member 23 is released, the joint member is removed from the intermediate casing, and excavation is performed. The coupling member is removed from the drilling machine 10, and the excavator rod 11 and the drilling bit 12 are mounted. Then, excavation is performed while circulating muddy water by the excavator 10 through the casing 20 installed underground. After excavation to a predetermined depth, as shown in FIG.
Pile 2 is constructed by casting concrete to the pile head position.
Next, the uppermost stage of the casing 20 used for the hole wall protection was used as the socket steel pipe 30, and as shown in FIG.
An annular concrete 31 is cast and the steel pipe column 8 is joined to the cast-in-place pile 2. FIG. 4 is a longitudinal sectional view showing a state where the cast-in-place concrete 2 and the concrete-filled steel pipe column 8 are joined together.
The pulling shear force can be ensured without constructing the footing as in the related art. The casing may be rotated by an excavator and pulled out, and only the casing used as the outer steel pipe for socket connection may be left, or the uppermost casing may be buried and the outer casing for socket connection may be left out. It may be used as a steel pipe. As described above, according to the present invention, by using the upper end of the casing for protecting the hole wall as the outer steel pipe for the socket for joining, the footing conventionally performed in the work adjacent to the track is used. Since the construction and the construction of the temporary earth retaining work are not required, and there is no need to inject the chemical solution, the track is not deformed, the construction is more efficient, the construction period can be shortened, and the construction cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram of a method of constructing a cast-in-place concrete pile serving as a hole wall protector by rotationally press-fitting a casing. FIG. 2 is an explanatory view of a method for joining a pile and a column using a casing as a socket steel pipe. FIG. 3 is a conceptual diagram illustrating socket joining. FIG. 4 is a longitudinal sectional view showing a state where a pile and a column are joined. FIG. 5 is an explanatory view of a pile construction method using hole wall protection by chemical injection. FIG. 6 is a diagram illustrating a method of joining a pile and a column via footing. [Description of Signs] 2 ... Cast-in-place concrete pile, 8 ... Steel pipe column, 10 ... Excavator, 11 ... Rod, 12 ... Drilling bit, 13 ... Reinforced basket,
20 ... Casing, 21 ... Tip casing, 22 ... Intermediate casing, 23 ... Joint member, 30 ... Outer steel pipe for socket, 31 ... Tubular concrete.

Claims (1)

Claims: 1. A step of rotationally press-fitting a casing to perform construction over a hole wall protection area, drilling the casing as a hole wall protection work, and placing concrete in the hole. A method of joining a pillar and a pile, comprising: a step of constructing a concrete pile by using the casing as an outer steel pipe of a socket joint; and a step of building a pillar in the outer steel pipe and joining the pillar to a concrete pile.