JP2993332B2 - Sliding form method used for reverse winding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding form method used in a reverse winding method.

[0002]

2. Description of the Related Art In general, a sliding formwork method comprises a formwork arranged along a cross-sectional shape of a structure, which is raised by a jack while taking a reaction force against a guide rod embedded in the structure. A concrete structure is constructed continuously upward by placing concrete in a frame.Compared to the method of repeating the work cycle of placing concrete and assembling, dismantling, and reassembling the formwork, Since the formwork can be moved upward in conjunction with the hardening time of the concrete while performing the casting and curing, there is an advantage that the work can be performed continuously.

[0003] On the other hand, the reverse winding method is a method mainly used when constructing an underground structure, in which a beam of a permanent structure or a slab of concrete is laid from above at the time of root cutting. With this as a support, the construction proceeds sequentially downward while supporting the retaining wall.

[0004] The present applicant has paid attention to the fact that the sliding form method is for constructing a concrete structure upward, while the reverse winding method is for constructing concrete downward. In addition, it has been found that if the sliding form method capable of continuously proceeding without the assembling and dismantling work of the form can be adopted for the reverse winding method, the work period can be significantly reduced.

[0005]

However, when the sliding form method is simply applied to the reverse winding method and concrete is poured into the form while the form is continuously lowered,
Unsettled concrete collapses due to its own weight and falls, so that the conventional sliding form method cannot be applied as it is.

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to prevent the unhardened concrete from dropping and to omit the assembling and dismantling operations of the formwork to continue the operation. The present invention provides a new construction method that can use a sliding form method that can be performed in a reverse winding method.

[0007]

In order to achieve the above object, the present invention is applied to a reverse winding method in which an inner winding wall is continuously formed below a retaining wall, and the inner winding wall is formed between the retaining wall and the retaining wall. The formwork constituting the closed cross section space is provided with a trim sheet which causes relative slippage between the formwork and the formwork on the concrete casting surface side, and is positioned at a predetermined position inside the earth retaining wall. A step of placing concrete in the sectional space and, after the concrete has hardened, a step of vertically lowering the form by an elevating jack and positioning the form at the next concrete placing position is sequentially repeated. In this invention
The mold is provided with a concrete
It is preferable to include a hopper section for placing the hopper. Sa
Furthermore, in the present invention, the formwork is lowered in the vertical direction.
When making the concrete, the closed section space where the concrete is cast next
The next closed cross section space located below the position to configure
After performing the re-arrangement work, the position of the next closed section space
It is preferred to raise to the position.

[0008]

According to the above construction, the formwork forms a closed section with the retaining wall, and is moved to the next concrete placement position after the concrete placed therein hardens. As a result, unhardened concrete will not fall. Concrete to be poured into the closed section space formed between the retaining wall and the formwork for each work cycle is continuously constructed below the existing concrete located above the concrete.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a sliding formwork method used in the reverse winding method according to the present invention. After an earth retaining wall 1 is constructed by an underground continuous wall method at almost the outer edge of an underground structure, it is defined by the earth retaining wall 1. The inner winding wall is connected to the inner side of the earth retaining wall 1 by a sliding form method while excavating and removing the earth and sand in the set portion in order from above.

A formwork 2 is disposed inside the retaining wall 1. The formwork 2 has a height dimension for constructing the inner winding wall for one rod, and faces the inner side surface of the retaining wall 1 via a distance corresponding to the thickness dimension of the inner winding wall to be constructed. A vertical section 2A, a concrete hopper section 4 projecting inward from the upper portion, and a sloped bottom section 2B are formed. Make up. A trim sheet (not shown) made of a hard polypropylene sheet or the like that causes relative slippage with the mold 2 is arranged on the concrete casting surface side of the mold 2.

The bottom 2B of the form 2 is penetrated by a guide rod 5 which also serves as a vertical main bar and extends vertically along the vertical direction of the inner winding wall to be constructed. A lifting jack 6 that moves up and down is provided integrally. In addition, a sealing material (not shown) is disposed above the through hole of the guide rod 5 at the bottom 2B of the formwork 2 to prevent the poured concrete from leaking from the through hole.

The jack 6 has a weight of the formwork 2 before concrete is cast, and against the weight of the formwork and concrete when concrete is poured into the formwork.
Is held at an arbitrary height position, and after the cast concrete is hardened, the concrete is cut off along the edge of the concrete and moves down along the guide rods 5.

Next, the procedure for constructing the inner winding wall using the above-described formwork device will be described.

First, in (a), the form 2 is installed below the uppermost inner winding wall C1 already constructed, and the form 2
1 shows a state after concrete C has been cast therein. It is needless to say that the inner winding wall C1 can also be constructed by the formwork 2. Further, as the concrete C, it is desirable to use concrete having good fluidity and expandability.

After the hardening of the concrete C, that is, at the time when the concrete C develops a strength enough to be self-supporting, the jack 6 is driven to lower the form 2 to remove the mold. The formwork 2 is smoothly removed by a small frictional resistance because a relative slip occurs between the formwork 2 and the edge cutting sheet,
A new inner winding wall C2 is integrally joined to the inside of the retaining wall 1 and below the inner winding wall C1.

As shown in FIG. 2B, the lower position of the mold 2 at the time of removing the mold is two rods, and a plurality of horizontal streaks 7 are arranged in a space for one rod formed above the mold 2. Is done. After the work of arranging the horizontal bars 7 is completed, the form 2 is raised by one span by the lifting operation of the jack 6 as shown in FIG. Become. In the stopped state, the concrete weight is applied in addition to the weight of the formwork. Therefore, it is desirable to fix the jack 6 by a lock mechanism anchored to the retaining wall 1, for example.

After the above preparation work, concrete C is poured into the form 2 through the hopper 4. And
The inner wall C
As shown in FIG. 2D, a new inner winding wall C3 is connected to the lower part of the second wall. Thereafter, by repeating the same working cycle as above, the inner winding walls C1, C2, C3,.
Are continuously constructed downward.

In the above embodiment, the form 2 is lowered by applying a reaction force to the guide rod 5, but an anchor is previously hit at a depth below a predetermined root cutting surface or a depth below a reverse winding body, and the reaction force is applied to this anchor. Can be used to drive the jack.

[0019]

As described in detail in the above embodiments, in the sliding formwork method used in the reverse winding method according to the present invention, the space between the inside of the retaining wall and the formwork is provided every work cycle. Since the concrete wall equivalent to the formed closed section space is continuously constructed downward, there is no need to assemble and disassemble the formwork each time concrete is poured, simplifying man-hours and shortening the construction period It is suitable for performing.

[Brief description of the drawings]

FIGS. 1A to 1D are cross-sectional views showing a construction procedure of a sliding formwork method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Retaining wall 2 Formwork 5 Guide rod 6 Jack C Concrete C1, C2, C3 ... Inner wall

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masami Ito 2-3-3 Kandaji-cho, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo Head Office (72) Inventor Shigeyuki Togawa 4-640 Shimoseito, Kiyose-shi, Tokyo Stock Company (72) Inventor Takayoshi Hirata 4-640 Shimoseito, Kiyose-shi, Tokyo Co., Ltd. Obayashi Corporation Technical Research Institute (56) References JP-A-63-97761 (JP, A) JP-A-49-55124 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E04G 11/22 E02D 29/045 E21D 13/00

Claims (3)

(57) [Claims] 1. A reverse casting method for continuously constructing an inner winding wall below a retaining wall, and forming a closed section space between the retaining wall and a concrete casting surface. On the side, a trim sheet that causes relative sliding with the formwork is installed and positioned at a predetermined position inside the retaining wall, concrete is poured into the closed section space, and the concrete is hardened Thereafter, a step of vertically lowering the form by a lifting jack and positioning the form at the next concrete placing position is sequentially repeated, and the sliding form method is characterized by being repeated. 2. The mold is formed so as to protrude inward at an upper portion.
It is specially equipped with a hopper for concrete casting.
Sliding used in the reverse winding method according to claim 1.
Formwork method. 3. When lowering the formwork in the vertical direction,
Of the closed section space where concrete is poured into the building
Position the bar below and work on the next closed section
After that, it is raised to a position that constitutes the next closed section space.
The reverse winding according to claim 1 or 2, wherein
Sliding construction method used for construction method.