JP2001164559A - Construction method of continuous underground wall guide wall making use of l-type precast member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the cast of cast-in-place concrete when a guide wall of a continuous underground wall is constructed and, at the same time, to make it possible to efficiently carry out the continuous execution of the guide wall to reduce a construction period of time. SOLUTION: Excavation is carried out from the ground surface G to the base surface GB of a guide wall. Then, leveling concrete 10 with specific width is cast on the base surface GB, bed mortar 11 is placed on the surface of the leveling concrete and, at the same time, L-type precast members 1 with specific length consisting of bottom plates 1b and sheathings 1a at right angles to the bottom plates 1b are arranged on the upper surface of the leveling concrete. Then, the following L-type precast members 1 are arranged in the longitudinal direction in succession, and joint sections 2, 2 and 2 of the L-type precast members 1 are connected to each other. The arrangement and connection of the L-type precast members 1, 1... are repeated, and the guide wall W is constructed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a continuous underground wall guide wall using an L-shaped precast member, and more particularly to a method of using a reinforced concrete L-shaped precast member manufactured in advance in a factory or the like. The present invention relates to a method for constructing a continuous underground wall guide wall.

[0002]

2. Description of the Related Art A construction procedure of a conventional continuous underground wall guide wall will be described with reference to FIG.

1: Excavation of a guide wall installation portion (Step 101) 2: Casting of leveling concrete to a base portion of the guide wall (Step 102) 3: Surveying and positioning of a guide wall base line Perform (Step 103) 4: Assemble the rebar at the base portion of the guide wall (Step 104) 5: Assemble the mold for forming the base (Step 10)
5) 6: Cast concrete on the base (Step 10)
6) 7: Assemble the reinforcing bar on the side wall of the guide wall (Step 107) 8: Assemble the formwork for forming the side wall (Step 10)
8) 9: Measure the top surface position of the guide wall and determine the top position of the concrete (Step 109) 10: Pour concrete into the side wall form (Step 110) 11: Cure the poured concrete (Step 109) 11
1) 12: After curing, dismantle the formwork (Step 112) 13: Backfill the excavated area around the guide wall (Step 113) 14: Perform construction work of a working floor for continuous underground wall construction (Step 114) After the mold is dismantled in the step 112, the step 1 is carried out for the next side wall to form the mold continuously in the longitudinal direction.
The construction is carried out while diverting to 08.

[0004]

According to the guide wall construction method, when the range of concrete cast in one place is long, there is a possibility that expansion and contraction cracks peculiar to cast-in-place concrete may occur, and it is extremely difficult to control the quality of concrete. Met. Also, in consideration of diversion of the formwork material, it is necessary to divide the concrete casting span into approximately 20 m and construct
It cannot be done continuously.

[0005] Further, since a preparatory work for concrete placement and a curing period after concrete placement (three days after casting) are required, the process may be extended, or the construction may be affected by weather conditions. Management becomes difficult. In addition, this construction method requires at least three types of work: rebar work, formwork carpenter, toby, and shibo, and mixed work occurs at the construction site, making adjustments in safety management and labor planning complicated. Become.

Therefore, when constructing the guide wall,
Construction of continuous underground wall guide wall that greatly reduces the need for cast-in-place concrete, reduces the number of construction steps, simplifies workability, and enables continuous construction. The technical problem to be solved arises in order to obtain the method, and the present invention aims to solve this problem.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been proposed to achieve the above-mentioned object, and is intended to provide a guide wall for constructing a continuous underground wall around a building, which serves as a pier for underground excavation. In the construction method, after digging from the ground surface to the base surface of the guide wall, a leveling concrete having a predetermined width is cast on the base surface, and furthermore, a mortar is laid on the upper surface, and the mortar is laid. An L-shaped precast member having a predetermined length composed of a bottom plate and a side plate formed at right angles to the bottom plate is disposed on the top, and then the next L-shaped precast member is disposed continuously in the longitudinal direction. The joint section of the precast member is joined to each other, and thereafter, the disposition and joining of the L-shaped precast member are repeated in the longitudinal direction, and the continuous underground wall guideway using the L-shaped precast member to construct the guide wall There is provided a method of constructing Lumpur.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS. FIG. 1 is an explanatory perspective view showing the construction state of the continuous underground wall guide wall W, and FIG. 2 is a plan view of the guide wall W. The construction of the guide wall W is carried out at first from the ground surface G along the planned construction position of the continuous underground wall installed around the building (not shown) with the backhoe B as shown in FIG. slope S to a portion of the base surface G _B of the guide wall W, drilling with a S. Thereafter, the bed with working compacting the base surface G _B as shown in FIG. 1 rolling in intensifier R or the like.

[0009] Next, install the bottom plate 1b of the L-shaped precast member 1 described later becomes the guide wall W as shown in FIG. 3, where the smoothing on said base surface G _B concrete 10 (height 50 mm) horizontally and with a predetermined width.
The laying position of the mold precast member 1 is measured and the laying position of the bottom plate 1b is determined. After that, a mortar 11 (height: 30 mm) is placed on the upper part of the leveling concrete 10 to prepare for the installation work of the L-shaped precast member 1 conveyed by the crane C.

As the L-shaped precast member 1, a member for an L-shaped retaining wall made of reinforced concrete manufactured in advance at a factory or the like under quality control is used. The member for the L-shaped retaining wall is generally provided with a hole for draining water. However, when manufacturing the L-shaped precast member used in the present invention, the box draining is stopped to eliminate the drainage hole. .

The L-shaped precast member 1 is formed in an L-shaped cross section as shown in FIG. 3, the back surfaces of the side plate 1a and the bottom plate 1b are perpendicular to each other, and the height of the side plate 1a is 1250 m.
m, and the width of the bottom plate 1b is 900 mm. Also, the side plate 1a
The thickness of the bottom plate 1b is tapered inward from the upper thickness of 120 mm to a thickness of 135 mm on the bottom plate 1b side, and the thickness of the bottom plate 1b is also reduced from the 135 mm thickness on the side plate 1a side to the bottom plate 1b. The inside is tapered so that the tip has a thickness of 90 mm.

On the other hand, the cross section L of the L-shaped precast member 1
As shown in FIG. 1, joint portions 2 for joining the L-shaped precast members 1 and 1 to each other in the longitudinal direction are provided on both side surfaces of the mold.
The bottom plates 1 and 2 are provided at three positions: a position at a predetermined interval above and below the side surface of the side plate 1a and a position near the center of the side plate 1b. As shown in FIG. 4 (a), the joints 2, 2, 2
It consists of a U-shaped steel plate welded to anchor bars 16, 16, 16, 16 embedded in the concrete of the mold precast members 1, 1 and has a central portion of the steel plate for inserting a bolt 18 for joint. The bolt holes 17 and 17 are drilled.
Also, as shown in FIG. 4B, the joint bolt 1 for joining the joints 2 and 2 is provided inside the joints 2 and 2.
Box removal part 1 to secure working space for 8 and nut 19
5 and 15 are provided when the L-shaped precast member 1 is cast into concrete. After the joining of the L-shaped precast members 1 and 1 is completed, the box blanks 15 and 15 are filled with mortar and back-filled for integration.

Even if the joints 2, 2, 2 of the L-shaped precast members 1, 1 are fastened with the joint bolts 18 and the nuts 19, some gaps are formed in the joints, and the underground continuous When the wall is constructed, there is a risk that the stable liquid may be lost. Therefore, as shown in FIG. 3, a sponge is formed along the cross section from the upper side of the side plate 1a to the vicinity of the center of the side surface of the bottom plate 1b to eliminate this gap. The tape 5 is adhered and trimming is performed.

As shown in FIG. 1, the guide wall W is provided with the bottom plate 1b of the L-shaped precast member 1 on the mortar 11, and the next L-shaped precast member 1 is moved by the crane C. The L-shaped precast members 1, 1
As described above, the joint bolt 18 and the nut 19 are joined in the longitudinal direction. However, since the longitudinal length of the L-shaped precast member 1 is as long as 2 m, the strength of the joined portion is weakened. As shown in FIG. 3, a tie 3 made of a channel steel is provided on the upper surface of the bottom plate 1 b and in the vicinity of the side plate 1 a so as to reinforce the back surface of the web portion of the channel steel along the upper surface of the bottom plate 1 b. The L-shaped precast member 1 is installed in the longitudinal direction of the L-shaped precast member 1, and anchor bolts 4, 4 are driven into the bottom plate 1 b of the L-shaped precast member 1 from the joining material 3 side to place the L-shaped precast member 1. Member 1, 1
Join each other. In addition, the connecting member 3 is connected to the joint portion 2,
In addition to the reinforcement of the L-shaped precast members 1, 2, it effectively works to prevent the L-shaped precast members 1, 1 from shifting in the horizontal direction.

As shown in FIG. 2, the straight portion of the guide wall W can be formed by continuously arranging the L-shaped precast members 1, 1, but the corner portions 13, 13 of the guide wall W can be formed. ... are the standard L-shaped precast members 1,
1 cannot be formed. Therefore, as shown in FIG. 5, the corner portions 13, 13... Are provided with a predetermined length of a reinforcing bar anchor 7, 7,... On the side surfaces of the side plate 1a and the bottom plate 1b of the L-shaped precast member 1. It is driven vertically at an interval of 200 mm, and the corners 13, 13 are connected by cast-in-place concrete. Further, at the joint 12 with the work floor 14 shown in FIG.
.. Of a predetermined length are vertically driven into the top end of the side plate 1a of the die precast member 1 at an interval of 200 mm, and the other end is bent at a right angle along the joint 12 to join the joint 12 Cast-in-place concrete (thickness 200
mm) to allow connection with the work floor 14.

In constructing the guide wall W, after completing one row of the L-shaped precast members 1, 1,..., The other row is formed in the same manner as described above in accordance with the design of the continuous underground wall. The guide wall W is completed by disposing the side plate 1a of the L-shaped precast member 1 to be formed while maintaining the side plate 1a of the L-shaped precast member 1 already installed at a predetermined interval. Thereafter, the excavated portion around the guide wall W is backfilled while compacting with the compactor R. In this case, as shown in FIG. 1, in order to maintain a space between the L-shaped precast members 1 and 1, .. Are installed in some places.

The method of arranging the L-shaped precast members 1, 1,... Forming the guide wall W is as follows. May be. Further, the cast-in-place concrete at the corners 13, 13... And the joints 12, 12.
4 will be built. Also, the joints 12, 12,...
As shown in Fig. 3 at the time of cast-in-place concrete,
At the opening of the guide wall W, a step is provided for installing the open curing steel sheet 9.

It should be noted that the size of the L-shaped precast member, the thickness of the leveling concrete, the thickness of the mortar and the like shown in the above-described embodiment are not limited to these, and may be changed as appropriate according to the design of the guide wall. Is done.

Thus, the present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified ones.

[0020]

As described above, the present invention uses an L-shaped precast member composed of a bottom plate manufactured in a factory or the like and a side plate formed at right angles to the bottom plate as a component of the guide wall. Rebar, formwork,
Work such as concrete casting can be largely labor-saving, and the number of types of work can be reduced, so that mixed work on site can be reduced and workability can be simplified. In addition, since the L-shaped precast member is disposed in the longitudinal direction and the joints are joined together, curing of the conventional cast-in-place concrete is not required. Construction can be continued and the construction period can be shortened.

Furthermore, with the decrease in cast-in-place concrete, the rate of use of South Sea wood as a form material can be reduced, and consideration for the global environment can be achieved. Thus, by using the L-shaped precast member for the construction of the guide wall, rapid construction becomes possible, and it is possible to greatly reduce the construction period and the construction cost.

[Brief description of the drawings]

FIG. 1 is an explanatory perspective view showing an embodiment of the present invention and showing a construction state of a continuous underground wall guide wall.

FIG. 2 is a plan view showing an installation state of a guide wall.

FIG. 3 is a sectional view taken along a line II in FIG. 2;

FIG. 4A is a plan view showing a joint portion of an L-shaped precast member. FIG. 4B is a cross-sectional view of FIG.

FIG. 5 is a perspective view showing a rebar anchor at a joint of the guide wall with a corner portion and a work floor.

FIG. 6 is a flowchart of a conventional guide wall construction.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 L-type precast member 1a Side plate 1b Bottom plate 2 Joint part 10 Leveling concrete 11 Mortar G Ground surface G _B Base surface W Guide wall

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Akio Kanamaru 2-10-5 Katamachi, Miyakojima-ku, Osaka City, Osaka Inside the Kumagaya Gumi Osaka Branch (72) Minoru Nakamura 2-chome Katamachi, Miyakojima-ku, Osaka, Osaka No. 10-5 F-term in Kumagaya Gumi Osaka Branch (reference) 2D049 EA02 GE00 GE09

Claims (1)

[Claims] In a method for constructing a guide wall for constructing a continuous underground wall serving as a mountain retaining when excavating underground around a building, after excavating from the ground surface to a base surface of the guide wall, An equalized concrete having a predetermined width is cast on the base surface, a mortar is further laid on the upper surface thereof, and an L-shape having a predetermined length including a bottom plate and side plates formed at right angles to the bottom plate on the mortar. The precast member is disposed, and then the next L-shaped precast member is disposed continuously in the longitudinal direction, and the joints of the L-shaped precast member are joined together. A method of constructing a continuous underground wall guide wall using an L-shaped precast member, wherein the guide wall is constructed by repeatedly arranging and joining the guide wall.