JP2961449B2 - How to make synthetic floorboards - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to the synthesis floorboard and its fabrication method using precast Concrete plate member as buried formwork.

[0002]

Synthesis floor BACKGROUND OF THE INVENTION Composite scheme, using precast concrete structure of the plate-like member as a buried type frame, and cast in place to form the concrete layer thereon, integrally with the concrete layer and the plate-like member The plate-like member is a formwork and becomes a part of the structural frame after the concrete layer cast in place on it is solidified. Therefore, the advantages of both the on-site driving method and the precast method can be utilized. Conventional composite floorboards 1 include, for example, FIGS.
There are the following. Method using the plate-like member 2 of the precast concrete Concrete thin embedded truss reinforcement 3 as formwork Yes shown in FIG. 9, the truss reinforcement 3, for example, as shown in FIG. 10, and the lower chord member 3a, Upper chord material 3b
And a lattice member 3c formed of a bending bar are joined in a truss shape by resistance point welding, and approximately half below the truss reinforcing bar 3 and reinforcing bars arranged vertically and horizontally are embedded in the concrete C1 of the plate-shaped member 2. Have been. Plate-like member 2 forming a formwork
Is disposed at a predetermined position above a beam or the like, reinforcing bars are arranged vertically and horizontally on the truss reinforcing bars 3, and are cast in place on the plate-like member 2 to form a concrete C2 layer, thereby obtaining the composite floor plate 1. Upper surface Yes in method using the plate-like member 6 of the flat precast concrete structure as formwork illustrated in Figure 11, the plate-like member 6 rebar is embedded in a matrix in the concrete C1, the cotter on the upper surface A large number of recesses 6a are formed.
The plate member 6 constituting the formwork is arranged at a predetermined position above the beam 7 and the like, and the reinforcing bars 8a and 8b are arranged vertically and horizontally on the plate member 6, and are hit on the plate member 6 in place. Two layers of concrete C are formed to obtain a composite floorboard 5.

[0003]

The construction method shown in FIGS. 9 and 10 requires a lot of time and effort to manufacture the truss reinforcing bar 3, so that the cost is high and the truss reinforcing bar 2 is provided on the upper surface of the plate-like member 2.
There is a drawback that the workability is poor because the upper half protrudes in a ridge shape. The construction method shown in FIG.
It is difficult to control the quality in order to form the shape of the recess 6a, and the man-hour and cost for forming the recess 6a increase.
However, there is a drawback that the integration of only the cotter by the method leaves uneasiness in long-term integration, durability and the like. The problem to be solved by the present invention is to provide a method of manufacturing a composite floorboard which does not have the drawbacks of the above-mentioned prior art, in other words, by using a steel spacer, a precast concrete which becomes a buried formwork. It is an object of the present invention to provide a method of manufacturing a composite floorboard that can ensure the integrity of a structural plate-like member and a cast-in-place concrete plate-like portion, and has good workability.

[0004]

The present invention employs the following structure as means for solving the above-mentioned problems. The structure of the present invention is directed to a first lattice-like iron having reinforcing bars arranged vertically and horizontally.
A plate-like member on the lower side of a precast concrete structure in which a reinforcing bar is embedded, and a second grid-like reinforcing bar in which reinforcing bars are arranged vertically and horizontally.
The upper side of the plate-shaped concrete structure of the embedded cast-in-place is
Firmly be integrally moiety and via a number of connecting reinforcing bars
That in the fabrication method of synthesis floorboards, as the coupling reinforcing bars, the first
The upper end of the concave receiving part that receives a part of the grid-shaped reinforcing bar
Using a self-supporting spacer made of steel bars provided for
The first grid-shaped reinforcing bar with vertical and horizontal reinforcing bars on top
And according to the distance between the vertical and horizontal reinforcing bars of the first lattice reinforcing bar.
At a number of positions on the formwork with the specified vertical and horizontal spacing,
Each is self the spacer and below each spacer
Is placed close to the first lattice reinforcing bar, and the
Pour concrete on top and lower part of each spacer
Embedded in concrete together with the first lattice reinforcing bar
And the upper part of each spacer is the concrete layer
The lower plate that protrudes in a dot-like manner at intervals on the surface
A plate-shaped member is manufactured, and the plate-shaped member is placed on a building beam or the like.
Is the upper part of the spacer placed on the upper side?
Then, a second lattice reinforcing bar is arranged above the plate-like member ,
A second case corresponding to the concave receiving portion at the upper end of each spacer.
Insert the rebar into the recessed receiving part at the upper end of each spacer.
After engaging, concrete is placed on the lower plate
And cast-in-place, of the cast-in-place second in the concrete
Embed the grid reinforcement and the upper part of each spacer
And cast-in-place concrete with the lower plate
Composite Slab characterized that you form a plate-shaped portion of the upper
In the manufacturing method . As a self-supporting spacer made of a steel bar, a recessed receiving portion for receiving a part of a second lattice reinforcing bar buried in cast-in-place concrete, and four legs are provided. Use a spacer consisting mainly of a steel rod that can be self-supporting on the formwork. In a preferred embodiment, a precast concrete structure to be a buried formwork is used.
The first embedded in the concrete of the lower plate-like member
Placing the desired between the vertical and horizontal intervals of a number of intersections of the grid-shaped reinforcing bar
A spacer is placed on the part on the formwork so that the desired vertical and horizontal spaced portions of the multiple intersections of the second lattice reinforcing bar embedded in the cast-in-place concrete are above the spacer receiving portion. To place a second lattice reinforcing bar
I do .

[0005] Further, according to the structure of the present invention , reinforcing bars are arranged vertically and horizontally.
Placed by the first lattice-like reinforcement is embedded Precast Concrete of the lower plate-shaped member formed by a reinforcing bar in a matrix
The upper part of the cast- in-place concrete structure in which the second lattice-shaped reinforcing bar is embedded is connected via a number of connecting reinforcing bars.
In the fabrication method of synthesis floorboards that have been integrally coupled to Te, before
As a connecting rebar, a steel bar is bent into an M shape to
The recessed receiving part where the
Forming an M-shaped piece with an indentation and two legs,
Bend the bar in an inverted U-shape to provide a central connection and two legs
The inverted U-shaped piece was formed, and the M-shaped piece was placed under the center receiving part.
The upper part of the connection part of the inverted U-shaped piece is
Using a spacer to self by legs, first on the mold
1 grid reinforcement, and the vertical and horizontal grid reinforcements
Multiplied on formwork that is spaced vertically and horizontally corresponding to the intersection of reinforcing bars.
At each number position, the spacers are each set with four legs
Self-supporting and connecting each leg of each spacer to a first grid-shaped reinforcing bar
Place the concrete close to the vertical and horizontal reinforcing bars and cast concrete on the formwork. The lower part of each spacer is the first case.
Rare embed in both in the concrete and the child-like rebar, and hide
The upper part of the pacer extends vertically and horizontally on the surface of the concrete layer
Form a lower plate-like member that protrudes in a dot-like manner at intervals, and places it on a building beam, etc., above each spacer.
After placing the lower plate-like member so they come to the upper, lower
Disposing a second grid-like reinforcing bars in the upper side of the side of the plate-like member, each space
The second case corresponding to this is
Engage the lower reinforcement at the intersection of the horizontal and vertical reinforcements
Corresponding to the protruding receiving part at the upper end of each spacer
Upper part of the intersection of the vertical and horizontal reinforcing bars of the second lattice reinforcing bar
Make sure that the lower side of the bar is engaged and the second grid bar is
Then , concrete is cast in place on the lower plate-like member, and the second lattice reinforcing bar and the upper portion of each spacer are embedded in the cast-in-place concrete to form a lower plate-like member. The upper plate made of cast - in-place concrete
A method for producing a composite floorboard, characterized by forming a part . The number of steel rods made of spacer decided in consideration of the strength of the spacer itself, the shear stress generated in the boundary layer between the plate member and Concrete plate portion of the cast-in-place of the precast concrete structure or the like, arranged a number of spacers The position of the intersection of the first grid-shaped reinforcing bars embedded in the plate-shaped member
Location , second case buried in cast-in-place concrete layer
Deciding in view of the position of intersection of the child-like reinforcing bar. It should be noted, horse
The planar shape of the plate-shaped member serving as the installation frame is a planar shape substantially matching the planar shape of the room space of the building, a shape obtained by dividing the planar shape into a plurality of shapes, and the like.

[0006]

According to each invention of this application, the lower part of a large number of steel rod spacers is buried in the concrete of the lower plate-like member made of precast concrete, and the upper part of each spacer is formed of concrete. Since it is buried in the cast-in-place concrete layer, the plate-like member and the cast-in-place concrete layer are firmly and integrally connected by a large number of steel rod spacers. A second grid buried in the cast-in-place concrete layer from the recessed receiving portion above the steel bar spacer;
Because the upper part of the spacer that protrudes from the lower plate-like member can be reliably supported, and the upper part of the spacer does not become ridge-shaped,
Workability is good without getting in the way.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, for example, as shown in FIGS. 1 and 2, a plan view shape of a room space surrounded by four pillars 31 of a building 30 being built, as shown in FIGS. To a plane shape that approximately matches
It can be installed on the beam 32. As shown in FIGS. 3 and 4, reinforcing bars 12a, 12 vertically and horizontally on the embedded frame 20
b to form a first grid-shaped reinforcing bar 12, and a desired interval 12 c between a number of intersections of the first grid-shaped reinforcing bar 12.
The spacer 13 made of steel rod is placed on the formwork 20 corresponding to
The four legs 13Ac and 13Bb are independently placed and arranged. For example, the spacer 13 shown in FIG. 5 is used. A steel bar is bent into an M-shape to form an M-shaped piece 13A having a concave receiving portion 13Aa into which one reinforcing bar fits, a protruding receiving portion 13Ab with which two reinforcing bars are in contact, and two legs 13Ac. And bending the steel rod into an inverted U-shape to form an inverted U-shaped piece 13B with a central connecting portion 13Ba and two legs 13Bb, and a central receiving portion 13Aa of the M-shaped piece 13A. On the lower side, the connecting portion 13 of the inverted U-shaped piece 13B
The upper side of Ba is joined by welding or the like, and the four legs
13Ac, 13Bb is a spacer 13 that can stand alone
Used. Each leg 13Ac, 1 of the spacer 13
The 3Bb portion on the side in contact with the mold 20 is provided with a rust-preventive coating 13C made of synthetic resin or the like as necessary. Spacer 13
Means that each leg 13Ac, 13Bb is a first lattice reinforcing bar.
Twelve reinforcing bars 12a and 12b are brought close to each other, and are connected to the grid-like reinforcing bars 12 as necessary. And Da設concrete C1 on the mold 20, embedding a lower portion and a lattice-like reinforcement 12 of the spacer 13 in the concrete C1, each spacer precast Concrete as a buried <br/> formwork
The upper part of 13 is vertically and horizontally on the surface of concrete C1 layer.
The plate-like members 11 projecting in a dotted manner at intervals are formed.

As shown in FIGS. 1 and 2, a plate-like member 11 is placed on a beam 32 bridged between columns 31 of a building 30 under construction, and the periphery of the plate-like member 11 is formed by a conventional method. Beam 32
And reinforcing bars 114a and 14b are arranged vertically and horizontally above the spacer 13 protruding from the upper surface of the plate-shaped member 11 .
The two reinforcing bars 14 are formed, and the reinforcing bars 14 are arranged such that a desired interval 14c of a large number of intersections is located above the protruding portion of the spacer 13. And
As shown in FIGS. 6 and 8, the portion of the horizontal reinforcing bar 14 b of the portion 14 c of the second grid-shaped reinforcing bar 14 is recessed in the M-shaped piece 13 A.
Fit to do it receiving portion 13Aa, vertical rebar 1 of the portion 14c
The receiving portion 13A of the M-shaped piece 13A protruding from the lower surface of 4a
b. Next, concrete C2 is cast (on-site) on the plate-like member 11 and the beam 32 serving as a formwork, and the portion above the spacer 13 (the remaining upper half) and the second grid-like reinforcing bar 14 are formed. Is embedded in the concrete C2 to complete the composite floorboard 10. This synthetic floorboard 10 is made of steel
Since the lower portion of the rod made of a number of spacers 13 are embedded in the concrete C1 Precast Concrete plate member 11, the upper portion of the spacer 13 is embedded in the concrete C2 layer in cast-in-place, steel Precast concrete with multiple rod- made spacers 13
And forming a plate-like member 11 and the poured concrete C2 layer is firmly bonded together. Therefore, the shear stress generated in the boundary layer between the precast concrete Concrete of the plate-like member 11 and the poured concrete C2 layer, since Ru is transmitted in a number of spacers 13 made of steel rod, maintaining the integrity and durability over a long period can do. Further, the recessed receiving portion 13Aa of the upper part of the spacer 13 and the protrusion
Cast- in-place concrete C2 with the receiving part 13Ab
Vertical and horizontal reinforcing bars 14 of the second lattice reinforcing bars 14 embedded in the layer
a, 14b can be reliably supported. Further, the plate-like member 11
Upper portion of the spacer 13 which projects from the arrangement in dots
Because it does not become ridged like truss rebar,
It is easy to walk on the plate-shaped member 11 and workability is good. In the embodiment, the spacers 13 are arranged so that the spacers 13 are located at the intersections of the first lattice reinforcing bars 12 embedded in the concrete C1, and the horizontal reinforcing bars 14b fit into the recessed receiving portions 13Aa of the spacers 13, impact of the spacer 13
The second lattice reinforcing bar 14 to be embedded in the concrete C2 is arranged so that the lower side surface of the vertical reinforcing bar 14a is in contact with the received receiving portion 13Ab.
Of the first lattice reinforcing bar 12 embedded in the cleat C1.
Buried in the area near the intersection and in the upper concrete C2
Near the intersection of the intersecting portions of the inserted second grid-like reinforcing bars 12
It can be firmly joined to the part via the spacer 13
it can.

[0009]

According to the method for manufacturing a composite floorboard according to the first aspect of the present invention, a part of the upper (second) lattice reinforcing bar is used as the connecting reinforcing bar.
Self-standing steel bar with a concave receiving part at the top for receiving
Using a spacer that can be used, arrange reinforcing bars vertically and horizontally on the formwork
A first lattice-shaped reinforcing bar, and a first lattice-shaped iron
Set the vertical and horizontal intervals determined according to the vertical and horizontal reinforcing bar intervals.
The spacers are placed in a number of positions on the
And place the lower part of each spacer on the first grid iron
Place it close to the streaks and cast concrete on the formwork
Then, the lower part of each spacer is the first lattice reinforcing bar.
Both are embedded in concrete and each spacer
The upper part is vertically and horizontally spaced on the surface of the concrete layer.
To produce a lower plate-like member that protrudes in the shape of a dot.
Place the member on a building beam, etc., above each spacer.
So that it is on the upper side, and then
A second grid-like rebar is placed on the side, and the upper end of each spacer
Insert the second grid-shaped reinforcing bar corresponding to the recess
Engage the recess on the top of the pacer
Cast concrete on the plate-like member
In the cast-in-place concrete, a second lattice reinforcing bar and each space
Embed the upper part of the circuit and
Form the upper plate-shaped part of cast-in-place concrete on the body
The lower part of the spacer made of a number of steel rods is first grid-shaped in the concrete of the lower plate-like member.
Buried in close proximity to the rebar, the upper part of each spacer is a second part in the upper slab of cast-in-place concrete .
Since close to the grid-like reinforcing bars Ru is embedded, the upper Concrete of the lower plate-like member and the cast-in-place by the spacer
The integration with the plate-shaped portion is further strengthened. Also, rebar
A self-standing steel bar with a recessed receiving part at the upper end
Precast concrete that can be used as a buried formwork because the spacer that can be cut is simpler and cheaper than truss rebar
The plate member on the lower side of the structure can be provided at low cost. Claims
Production method of synthesis floorboards of the invention according to 1, the space <br/> Sa desired number from that spaced in the desired position, the lower
On a portion of the second grid-like reinforcing bars embedded in the concrete layer of the cast-in-place to arrange above the plate-shaped member of each spacer
It can be received by engaging with the concave receiving part at the end.
As a result, the second grid-like reinforcing bars can be arranged neatly without disturbance. The upper part of the steel bar spacer protruding from the plate-like member is point-shaped and does not become ridged like a truss rebar, so when walking on it, the protruding spacer part does not interfere with the workability Is improved. Those of the invention according to claim 1, as compared with the prior art forming the recess to serve as the cotter on the upper surface of the precast concrete Concrete plate member,
The process of forming recesses, which is difficult to manage, can be omitted, and
On the Concrete of the lower plate-like member and the cast-in-place for formation
It is possible to easily ensure the integration with the side plate-shaped portion . The method of manufacturing a composite floorboard according to the invention according to claim 2 is characterized in that:
As a reinforcing bar, a steel bar is bent into an M shape, and one reinforcing bar fits
A protruding receiving part where two rebars come into contact with a completely concave receiving part
And an M-shaped piece with two legs and a steel bar
Bent into an inverted U-shape with a central connection and two legs
Form an inverted U-shaped piece, and under the center receiving portion of the M-shaped piece
The four U-shaped pieces that are connected by
Use a spacer that is self-supporting on the legs and place the first
A grid-shaped reinforcing bar, and vertical and horizontal reinforcing bars of the first grid-shaped reinforcing bar
Multiple vertical and horizontal spaced formwork corresponding to the intersection of
Position the spacers independently on four legs
And each leg of each spacer is positioned vertically on the first grid
Place the concrete close to the horizontal rebar and place the concrete on the formwork.
And the lower part of each spacer is shaped like a first grid.
Embedded in the concrete together with the reinforcing steel
The upper part of the sir is vertically and horizontally spaced on the surface of the concrete layer
To form a lower plate-like member that projects in a point-like manner,
The upper part of each spacer is placed on a building beam, etc.
After placing the lower plate-shaped member so that it comes to the side,
A second lattice reinforcing bar is arranged above the plate-like member, and each spacer
The corresponding second grid in the recess at the upper end of the
Engage the lower reinforcing bar at the intersection of the reinforcing bars
The corresponding protruding part at the upper end of the spacer
Below the upper reinforcing bar at the intersection of the vertical and horizontal reinforcing bars of the 2 grid reinforcing bars
Side and engage the second grid bar, then lower
Pour concrete on the side plate-like member
In the cast-in-place concrete, a second lattice reinforcing bar and each space
Embedded in the upper part of the heat sink
Integrally form the upper plate-shaped part of cast-in-place concrete
From a cast-in-place arrangement above the lower plate
Intersection of the second lattice reinforcement buried in the concrete layer
The lower rebar to the recessed receiver at the top of each spacer.
In the vicinity of the intersection of the second lattice reinforcing bars
The lower side of the upper rebar is projected from the upper end of each spacer.
Arrange the reinforcements without disorder by engaging and receiving the parts
Can be In addition, a second on the top of each spacer
So that the reinforcing bars at the intersections of the grid bars of
Since the reinforcing bars can be arranged, a buried formwork is constructed.
Bottom plate to be cast and top of cast-in-place concrete
The spacers strengthen the integration with the
Can be

[Brief description of the drawings]

FIG. 1 is a plan view showing a relationship between a building and a plate-like member in an embodiment.

FIG. 2 is an elevational view of the one shown in FIG. 1 taken along the line AA.

FIG. 3 is a plan view showing a method of manufacturing a plate member used in the embodiment.

FIG. 4 is an elevational view of the one shown in FIG. 3 taken along the line BB;

FIG. 5 is a perspective view of a steel rod spacer used in the embodiment.

FIG. 6 is an elevation view showing a relationship between a steel bar spacer and a reinforcing bar in the embodiment.

FIG. 7 is a plan view showing a method of manufacturing a composite floorboard of the embodiment.

FIG. 8 is an elevational view of the one shown in FIG. 7 taken along the line CC.

FIG. 9 is a perspective view showing a method of manufacturing a conventional synthetic floorboard.

FIG. 10 is a perspective view of a truss reinforcing bar used for manufacturing the composite floor panel of FIG. 9;

FIG. 11 is a perspective view showing another method of manufacturing a conventional synthetic floorboard.

[Explanation of symbols]

10 Composite Slab 11 Precast Concrete plate member 12 first grid-like reinforcing bars 12a vertical rebar 12b transverse reinforcing bar 13 steel bar made of the spacer 14 and the second grid shaped reinforcing bars 14a vertical rebar 14b transverse reinforcing bar 20 Formwork C1 concrete C2-site Pour concrete

────────────────────────────────────────────────── ─── Continuing on the front page (72) Naoki Aso, Inventor Naoki 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Corporation Inside the Tokyo Head Office (72) Inventor Akira Shimizu 8-2-1-1, Ginza, Chuo-ku, Tokyo Takenaka (72) Inventor Katsuhito Ohata, Tokyo, Japan 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Corporation (72) Inventor, Masaru Matsuzaki 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Corporation Store Inside the Tokyo head office (56) References Open to the public Showa 54-140514 (JP, U) Open to the public Showa 63-78614 (JP, U) Open to the public Showa 58-177446 (JP, U) (58) Fields investigated (Int) .Cl. ⁶ , DB name) E04B 5/38 E04B 5/32

Claims (2)

(57) [Claims] 1. A first lattice reinforcing bar having reinforcing bars arranged vertically and horizontally.
The lower plate-like member of the precast concrete structure with embedded steel and the second grid-like reinforcing bar
Embedded cast- in-place concrete upper plate
In minutes and is rigidly manufactured method <br/> synthesis floorboards that are integrated through an number of coupling reinforcing bars, as a connection reinforcement, the second
The concave receiving part that receives a part of the lattice reinforcing bar
Use a self-supporting spacer made of steel bars equipped with
A first grid-like reinforcing bar with reinforcing bars arranged vertically and horizontally
And determined according to the distance between the vertical and horizontal reinforcing bars of the first lattice reinforcing bar.
At various positions on the formwork with vertical and horizontal spacing
Freestanding said spacers and the lower part of each spacer
And place it close to the first grid-shaped rebar and place it on the formwork.
Cast concrete, and the lower part of each spacer
Embedded in the concrete together with the first lattice rebar,
The upper part of each spacer is the surface of the concrete layer
The lower plate-shaped part that protrudes in a point-like manner at intervals in the vertical and horizontal directions
Material, and place the plate-like members on the beams, etc. of the building.
So that the upper part of the
A second lattice reinforcing bar is disposed above the plate-like member , and
A second grid corresponding to the recessed receiver at the top of the pacer
Engage the rebar with the concave receiving part at the top of each spacer
And then place the concrete on the lower plate
Pour the second grid into this cast-in-place concrete
Embed the reinforcing bars and the upper part of each spacer, and
The upper side of the cast-in-place concrete integrally with the plate member on the side
Fabrication of Composite Slab characterized that you form a plate-like portion of the
Law . 2. A first grid-shaped reinforcing bar having reinforcing bars arranged vertically and horizontally.
The lower plate-like member of the precast concrete structure with embedded steel and the second grid-like reinforcing bar
Embedded cast- in-place concrete upper plate
In minutes and the fabrication method of synthesis floorboards that are coupled together via a number of connecting reinforcing bars, as the coupling reinforcing bars, the steel rod
Bent into an M-shape, and a concave receiving
With a protruding receiving part and two legs
To form an M-shaped piece and bend the steel bar into an inverted U-shape
Forming an inverted U-shaped piece with a central connection and two legs,
Under the center receiving part of the M-shaped piece,
A space that is self-supporting with four legs
A first grid-shaped reinforcing bar is arranged on a formwork using a heat sink , and a vertical length corresponding to the intersection of the vertical and horizontal bars of the first grid-shaped reinforcing bar.
In each of the numerous positions on the formwork
Spacers are self-supporting with four legs and each spacer
<br/> arranged each leg brought close to the vertical and horizontal rebar first grid-like reinforcing bars, and Da設concrete on the formwork, the lower portion of each space <br/> Sir the first of the grid-shaped reinforcing bars are both concrete <br/> preparative to embed rare in, and the upper portion of each spacer co
Dot protruding vertically and horizontally on the surface of the concrete layer
The lower plate-like member is formed, on the beam of a building, its
Upper portion of each spacer from the place the lower <br/> plate-like member to come to the upper side of the second on the side of the lower plate-like member
With a grid-shaped reinforcing bar, and a concave support at the upper end of each spacer
Of the vertical and horizontal reinforcing bars of the second grid-shaped reinforcing bar corresponding to this
Engage the lower reinforcing bar at the top of each spacer.
Length and width of the corresponding second lattice reinforcing bar
The lower side of the reinforcing bar above the intersection of the reinforcing bars of the
After placing the grid-type reinforcing bars , concrete is cast in place on the lower plate-like member, and this concrete
And the upper part of each of the spacers and the second lattice reinforcing bar
And forming an upper plate-like part made of cast-in-place concrete integrally with the lower plate-like member.