JP3445419B2 - Double slab construction 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 double slab construction method using a half precast concrete slab with an upper surface cotter that also serves as a temporary facility.

[0002]

2. Description of the Related Art In a building such as a steel-framed reinforced concrete structure having a plurality of basements, a double slab is usually formed at the bottom of an underground structure. This double slab is formed by erecting a foundation beam from a pressure plate provided at the root cut bottom of the excavated ground and connecting a floor slab to the upper end of the foundation beam. This is the same as far as the double slab on the bottom floor is concerned even in the case of the reverse striking method in which the frame is constructed sequentially from the first basement floor to the lower floors.
For example, in the reverse driving method when the basement floor is the third floor, the following work procedure is generally performed. (1) After the floor beam structure of the second basement floor is completed, excavate the ground to the floor level of the third basement floor, strike temporary waste concrete at the root cutting bottom, and use the temporary waste concrete floor as the working floor Build outer walls, pillars, etc. At this time, when the underground outer wall needs to be reinforced, an oblique cutting beam is temporarily installed between the underground outer wall and an appropriate beam on the ceiling of the floor. (2) The ground will be finally excavated and floored together with the above-mentioned waste concrete, and after appropriate ground work, the required bar arrangement will be made and concrete will be placed to construct a pressure plate. (3) After assembling the frame work scaffold for temporary work passage platform on the pressure resistant plate and using the frame work scaffold as a platform to provide the temporary work passage, the temporary work passage is used to form a foundation on the pressure plate. A beam form is assembled, a required reinforcement is given in the form, concrete is poured, and a foundation beam is jointed to a pressure plate. The foundation beam formwork, temporary work passage, framework scaffolding and the above-mentioned diagonal cutting beams will be appropriately dismantled and removed after the concrete strength of the foundation beam has reached a certain level of strength. (4) Assemble the floor slabs, which consist of floor slabs, opening-forming slabs for each pit, thick timbers, and hauling timbers, in each pit surrounded by foundation beams, and withstand pressure. After arranging the required formwork supports in various places on the slab and supporting those slab forms, the required reinforcements are placed on those slab forms and foundation beams, and concrete is placed. To build a floor slab for the basement beam and the third floor below ground. The slab formwork and the formwork support are dismantled after the slab concrete that has been cast exhibits a predetermined strength, and then disassembled and carried out through the openings of the pits formed by the opening forming dams. (5) After completing the work in the pit, close the opening for the temporary material discharge in the pit.

[0003]

However, such a double slab construction method has the following problems. Temporary work passages and frame scaffolds for erection of these are required at the time of foundation beam construction, and at the time of construction of floor slabs, floor slabs, pits for forming temporary material carrying-out openings in pits, and thick timber. ,
In addition to requiring a floor slab formwork made of a large drawing material and the like, a large number of formwork support materials for supporting these floor slab formwork are required, and a huge amount of temporary material is required. It takes a lot of labor and time to carry in and carry out, assemble and dismantle the enormous amount of temporary materials, which is a cause of prolonging the construction period. In particular,
In a closed, dark and narrow space pit, a large amount of temporary materials require work such as loading / unloading, assembling / disassembling, etc., which is not only difficult to work, but also leads to deterioration in quality. The working environment is bad, causing safety and hygiene problems for workers. Since the floor slab requires at least one opening (so-called useless hole) for each pit for loading / unloading temporary materials, other materials, working machinery / equipment, and workers in / out, etc. Post-treatment is required to close those openings after the work is completed. As a whole, it causes considerable cost and other disadvantages.

By the way, the conventional reverse hitching method includes: The floor slab formwork of the lower floor is hung with a plurality of steel rods hung from the slab of the constructed upper floor (suspension formwork), and the slab formwork is sequentially arranged according to the progress of the excavation work on each underground floor. A method of lowering the floor to the lower floor and constructing the floor slab on that floor (Japanese Patent Publication No. 52-3
3895 publication). B. Suspend precast concrete slabs on the basement floors of multiple floors in the upper floor in a state of being stacked in advance, and lower these precast concrete slabs to the lower floors according to the progress of the excavation work on each basement floor. A construction method in which the floor slabs for each floor are incorporated in order from the top (JP-A-3-262833). There is. As a half precast concrete slab that forms a composite structure with a cast-in-place concrete layer, C.I. Precast concrete slab for synthetic floors with a large number of short columnar recesses formed on the surface at regular intervals (Japanese Patent Publication No. 2-14500).
Issue). There is a synthetic floor construction method using the half precast concrete slab. However, the above problems cannot be solved even by these construction methods.

Therefore, in the present invention, in the construction of a double slab, a half precast concrete slab forming a part of a floor slab or a precast concrete slab forming a permanent setting form is reasonably used in a certain state. By doing
The present invention is intended to solve the various problems described above.

[0006]

According to the invention of claim 1, at the final stage of the reverse driving method, a foundation beam is erected from a pressure plate provided at the root cutting bottom of the excavated ground, and a floor slab is provided at the upper end of the foundation beam. In the double slab that is connected with, in the construction of the floor slab, using a half precast concrete slab with a top cotter that forms a part of the slab for each pit surrounded by the foundation beam, with these top cotters Half-precast concrete slabs are made in their original positions where they should be used, and before they are used as floor slabs, they are hoisted to a specified level above the main installation position with a plurality of suspending materials suspended from the slabs on the upper floors, respectively. After providing the board for temporary use such as a work corridor, constructing a pressure resistant plate and foundation beam based on the temporary use, remove the scaffold board, and half precast with each top cotter The crepe slab is placed on the periphery of the foundation beam of each pit to close each pit, floor reinforced concrete is placed on these half-precast concrete slabs with top cotters and foundation beams, and in-place concrete is placed. It is characterized by constructing a synthetic floor slab in which the cast concrete and each half-precast concrete slab with an upper surface cotter are integrally connected via a cotter.

According to the second aspect of the invention, in the final stage of the reverse driving method, the foundation beam is erected from the pressure plate provided at the root cutting bottom of the excavated ground,
In the double slab in which a floor slab is connected to the upper end of the foundation beam, the excavated ground on the bottom floor is first moved to the bottom floor level.
A root precut concrete slab with an upper surface cotter at the original position to be used is formed on the work floor by step-cutting and placing a temporary waste concrete on the bottom of the first step root. Each half of the pits formed by enclosing the slab by the above, and before using these half-precast concrete slabs with top cotters as floor slabs, the main installation position was hung with a plurality of suspension members suspended from the slabs on the upper floor. Jack up to the above predetermined level and lift it, and use the scaffolding board to provide temporary use for work passages and the like, and then, under the temporary use, further excavate the excavated ground together with the temporary waste concrete. The second step root cutting to the industrial level, and the buried concrete is placed on the second step root cutting bottom,
After constructing a pressure resistant plate and a foundation beam on the buried concrete, the scaffolding plate was removed, and each top cotter-equipped half precast concrete plate was placed on the peripheral portion of the foundation beam of each pit to close each pit. On these half-precast concrete slabs with top cotters and foundation beams, floor reinforcement is applied and in-situ concrete is placed.
It is characterized by constructing a synthetic floor slab in which the cast concrete and each half-precast concrete slab with an upper surface cotter are integrally connected via a cotter.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show an embodiment according to the present invention, in which (1) to (9) in FIGS. 1 to 4 are steel frames of which the basement floor is the third floor constructed by the reverse driving method. The working procedure of the double slab construction method in a reinforced concrete construction or a building of reinforced concrete construction is shown, and the construction method will be sequentially described below based on this work procedure.

(1) Construction of the second-floor basement structure (Fig. 1) The second-floor basement structure is constructed by the reverse driving method. In other words, the ground 1 is root-cut to the level below the beam on the floor of the second basement floor, and the temporary waste concrete 2 is placed at the bottom of the root, and the ground is directly supported on the temporary waste concrete as beam reaction force. Frame 3 again
A slab formwork 5 is arranged through a slab support structure 4 such as a foam synthetic resin block and a pipe support, reinforcement is given in these formworks, and concrete is placed to construct a slab 6 on the second basement floor. . Although not shown in the figure, the underground outer wall, pillars, etc. on the second basement floor are constructed by the usual construction means in the reverse construction method.

(2) First-stage root cutting of the third-floor basement and construction of the third-floor skeleton (Fig. 1) The ground 1 of the third-floor basement up to the floor level of the third-floor basement and the above-mentioned temporary concrete 2 First step is root cutting. At this time, the previous beam form 3, slab support 4 and slab form 5 are disassembled and removed together. In addition, the work floor 8 is temporarily installed by striking the temporary waste concrete 7 for the work floor on the bottom of the first-step root cutting on the third basement (see Fig. 1 (3)). Then, although not shown, on the work floor 8, an underground outer wall, a pillar, etc. of the basement on the third floor of the basement are constructed by a normal construction means in the reverse construction method,
When the underground outer wall needs to be reinforced, diagonal beams are temporarily installed between the underground outer wall and an appropriate beam on the ceiling of the floor.

(3) Manufacture of half precast concrete slab with top cotter (Fig. 1) On the above-mentioned work floor 8 which has been temporarily installed, a release material is made to correspond to each pit of the foundation beam which is later constructed in a planar lattice shape. 9 is directly applied, and a wooden PC form 10 having a required shape is fixed, and half precast concrete slabs 11 with an upper surface cotter to be used in situ are prepared. As a concrete production means, for example, a bar arrangement, a required manhole hole formwork are arranged in the PC formwork 10, concrete is placed, and a cotter (unevenness) is put on a plywood board on the placed concrete. A cotter mold material to which a forming sheet is attached is placed and pressed down, and vibration is applied so that the poured concrete is spread evenly and closely without any gap, and cured until a predetermined strength is exhibited.

(4) Temporary use of half precast concrete slabs with top cotters (Fig. 2) Half precast concrete slabs with top cotters
From the four corners of 11, the hanging rods 12 are erected vertically.
Through the small holes 13 in the slab 6 on the second basement, and the jack mounts 14 are placed on the slab 6 so as to correspond to the suspension rods 12, and the jacks 15 are respectively attached to these jack mounts. , And each hanging rod 12 is jacked up to raise each half-precast concrete slab 11 with a top cotter about 1 m from the working floor 8. Then, attach the upper end of each hanging rod 12 to the washer 16
And fix it to the slab 6 with the nut 17 (see Fig. 2 (5)).
The jack base 14 and the jack 15 are removed and diverted to another. The suspension rod 12 may be a wire or other suspension material (the same applies hereinafter). Moreover, scaffolding boards 18 are appropriately hung between the half precast concrete slabs 11 with top cotters (see FIG. 5), and the required temporary handrails 19 and skirting boards 20 are attached to temporarily install work passages 21 and material storage areas. .

(5) Second stage root cutting of the third basement (Fig. 2) The PC formwork 10 is removed using the working passage 21 and the like, and the excavated ground 1 is replaced with the working floor 8 The second stage root cutting will be done together to the geotechnical level. In this case, the distance from the work passage 21 or the like to the root cutting bottom is, for example, about 5 m. If the building uses pile foundations, the pile heads will be removed at this time. After that, buried concrete 22 is placed as a ground work on the second step root cutting bottom, and temporary stairs 23 are provided between the buried concrete and the work passage 21 (see FIG. 3).
(See (6)).

(6) Construction of pressure-resistant plate (Fig. 3) Using the work passage 21, the temporary stairs 23, etc., a bar is arranged on the above-mentioned buried concrete 22 and concrete is placed to withstand pressure. Build version 24.

(7) Construction of foundation beam (Fig. 3) Using the above work passage 21, temporary stairs 23, etc., beam reinforcement is arranged on the pressure-resistant plate 24 thus completed, and the foundation beam form (not shown) is provided. No.) is assembled, concrete is placed in the foundation beam formwork and is spliced to the concrete of the pressure plate 24, and after the predetermined strength is developed in the placement concrete, the foundation beam formwork is dismantled and removed. Then, the foundation beam 25 in the form of a grid in plan view standing upright from the pressure plate 24 is constructed.

(8) Placement of half-precast concrete slab with top cotter (Fig. 4) Remove all of the above-mentioned work passage 21, scaffolding plate 18, temporary handrail 19, skirting board 20, temporary stairs 23, etc. forming material storage ,Also,
On the slab 6 on the second basement floor, the jack mounts 14 and the jacks 15 are engaged again with the hanging rods 12 at the four corners of each half-precast concrete slab 11 with the upper surface cotter, and the washer 16 and the nut 17 from each hanging rod 12 are engaged. By removing, by jacking down those hanging rods 12, the half precast concrete slab 11 with each upper surface cotter is lowered, and thus, the peripheral edge of each half precast concrete slab 11 with each upper surface cotter, of the above-mentioned foundation beam 25. The pits 26 are closed by placing them on the peripheral edge portion of the foundation beam of each pit 26 formed inside the enclosure via a sloppy stopper (not shown). Then, those jack mounts 14 and jacks
Each small hole of the slab 6 on the 2nd basement floor after removing 15 and hanging rod 12 etc.
Block 13

(9) Construction of composite floor slab (Fig. 4) Floor reinforcement is applied on the half precast concrete slab 11 with a top cotter and the foundation beam 25 which are fixed,
Pour concrete and pour them into the half-precast concrete slab with top cotter 11 and foundation beam 25, and place the cast concrete and each half-precast concrete slab with top cotter together through the cotter. A synthetic floor slab 27 is constructed (see FIG. 6).

[0018]

According to the present invention, in a double slab in which a foundation beam is erected from a pressure plate provided at the root cutting bottom of excavated ground, and a floor slab is connected to the upper end of the foundation beam, the floor slab is constructed. In, before using the half precast concrete slab 11 with a top cotter forming a part of the floor slab, as a floor slab,
Since it is used for temporary use by suspending it at a predetermined level other than the permanent position at the use location, most of the temporary work passages and material storage areas required for the construction of the foundation beams are the half precast concrete slab 11 with the upper cotter. It can also be used as a temporary work passage for constructing foundation beams and temporary materials for material storage etc. can be reduced as much as possible, and after that, a half precast concrete slab with a top cotter 11 that forms a part of the floor slab is used. Since the floor slab is constructed by placing it in the permanent position and pouring in-place concrete, a huge amount of temporary material that has been conventionally required at the time of construction of the floor slab, that is, a floor slab at each place, It is not necessary to use a floor slab form made of a weir board for forming the temporary material unloading opening in the pit, a thick timber, a pulling bar, etc., and a large number of form support materials for supporting these floor slab forms. Therefore, the temporary materials can be significantly reduced. Further, as described above, it is possible to minimize the temporary materials required for the construction of the foundation beams, such as temporary work passages and material storage areas, and no floor slab formwork or formwork support material is required during floor slab construction. , The time and cost of assembling / disassembling and carrying in / out can be greatly reduced, and the construction period can be shortened. And, in the past, a large amount of temporary material was carried in and carried out in a closed, dark and narrow space pit.
Since the work of carrying out, assembling, dismantling, etc. can be completely eliminated, work can be facilitated, high quality can be secured, the work environment can be improved, and safety and hygiene problems for workers can be avoided. Solvable. Of course, in the floor slab, as in the past, temporary materials, other materials, loading and unloading of working machinery and equipment,
Since it is not necessary to provide openings (so-called useless holes) for each pit for the entry and exit of workers, post-processing for closing those openings is also unnecessary. Overall, the cost can be significantly reduced, and safety, economy, workability, and quality can be improved.

Since the half precast concrete slab 11 with a top cotter is manufactured at the original position to be used,
For temporary use, it can be lifted up a little on the spot, and for permanent use, it can be lowered on the spot, so there is no need for transportation, loading, or lifting, and handling is simple and easy. It's easy. Furthermore, since the floor slab is made into a synthetic floor slab by pouring and integrating on-site cast concrete on the half precast concrete slab, the thickness does not become particularly thick. The floor slab is a synthetic floor slab 27 that is made by injecting and integrating in-situ cast concrete on the half precast concrete slab with top cotter 11 to make it an adhesive property between the half precast concrete slab and in-situ concrete. It can be increased significantly.
According to the present invention, the work procedure can be rationalized and the work can be performed according to the specific steps.

[Brief description of drawings]

FIG. 1 is a procedure explanatory view showing an embodiment according to the present invention and showing work procedures (1) to (3).

FIG. 2 is a work procedure (4) to (5) in the same embodiment.
FIG.

FIG. 3 is a work procedure (6) to (7) in the same embodiment.
FIG.

FIG. 4 is a work procedure (8) to (9) in the same embodiment.
FIG.

FIG. 5 is a plan layout view of a work passage and a material yard by a half precast concrete slab with a top cotter in the same embodiment.

FIG. 6 is an enlarged cutaway side view of the composite floor slab according to the same embodiment.

[Explanation of symbols]

1 ... Ground 2 ... Temporary abandoned concrete 3 ... Beam form 4 ... Slab support 5 ... Slab form 6 ... Slab 7 ... Temporary abandoned concrete for work floor 8 ... Work floor 9 ... Release material 10 ... PC form 11 ... Top Half precast concrete plate with cotter 12… Suspension rod 13… Small hole 14… Jack stand 15… Jack 16… Washer 17… Nut 18… Scaffolding board 19… Temporary handrail 20… Baseboard 21… Work passage 22… Abandoned concrete 23 … Temporary stairs 24… Pressure plate 25… Foundation beams 26… Pits 27… Composite floor slabs

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ikuo Matsumura Inventor Ikuo Matsumura 8-21-1 Ginza, Chuo-ku, Tokyo Stock Company Takenaka Corporation Tokyo Main Store (72) Inventor Takaaki Shimizu 8-21-1 Ginza, Chuo-ku, Tokyo No. Stock Company Takenaka Corporation Tokyo Main Store (56) Reference JP 6-167031 (JP, A) JP 3-262833 (JP, A) JP 3-100225 (JP, A) JP 4-49333 (JP, A) JP-A-7-189396 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) E02D 29/00 E04B 5/38

Claims (2)

(57) [Claims] 1. A double slab in which a foundation beam is erected from a pressure plate provided at the root cutting bottom of the excavated ground at the final stage of the reverse driving method, and the floor slab is connected to the upper end of the foundation beam. In the construction of, using the half precast concrete slab with the top cotter that forms a part of the floor slab for each pit surrounded by the foundation beam, these half precast concrete slabs with the top cotter should be used respectively. Before using it as a floor slab, lift it up to a predetermined level above the main installation position with a plurality of hanging materials that are hung from the slabs on the upper floor and use it as a scaffolding board for temporary use such as work corridors. After constructing pressure resistant plates and foundation beams based on the temporary use, the scaffolding boards were removed and the half precast concrete slabs with top cotters were installed around the foundation beams of each pit. Placed at the edge to close each pit, give floor reinforcement to these half precast concrete slabs with top cotters and foundation beams, pour on-site cast concrete, and place the cast concrete and each top cotter A double slab construction method characterized by constructing a synthetic floor slab integrally joined with a half precast concrete slab with a cotter. 2. A double slab in which a foundation beam is erected from a pressure plate provided at the root cutting bottom of the excavated ground at the final stage of the reverse driving method, and a floor slab is connected to the upper end of the foundation beam. First, the excavated ground of No. 1 is root-cut to the lowest floor level,
Forming a working floor by placing temporary waste concrete on the step root cutting bottom, and on the working floor, a half precast concrete plate with an upper surface cotter to be used in-situ is formed by surrounding with the foundation beam Produced for each pit, these half precast concrete slabs with top cotter,
Before using it as a floor slab, jack it up to a predetermined level above the main installation position with a plurality of suspenders hanging from the slabs on the upper floor and lift the scaffolding board to temporarily use it as a work corridor or other temporary use. Then, under the temporary use, the excavated ground is further second-stage root cut to the groundwork level together with the temporary waste concrete, and the second-stage root cutting bottom is filled with buried waste concrete. Then, after constructing a pressure resistant plate and a foundation beam on the buried concrete, remove the scaffolding plate and place each half-precast concrete plate with a top cotter on the periphery of the foundation beam of each pit to form each pit. Blocked, floor reinforcement is placed on these half precast concrete slabs with top cotters and foundation beams, and on-site cast concrete is cast, and the cast concrete and each top cotter are placed. Double slab construction method and can Precast concrete panel which is characterized in that to construct a synthetic deck coupled together via a cotter.