JPH11286005A - Production of stairs of precast concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce an expense for a form by a method in which a prescribed number of tread step parts having a triangular cross section are concrete- molded, after that, by concrete-molding stair floor parts, a prescribed number of the tread step parts are bonded integrally in the shape of saw teeth. SOLUTION: A form 10 for molding a tread step part comprises recessed parts 11 arranged in parallel, one surface of each recessed part 11 is a molding surface 12 for a tread surface, and the other surface is a molding surface 13 for a riser surface for concrete-molding the riser surface. By placing concrete in each recessed part 11, tread step parts 5 having a triangular cross section are molded simultaneously in a state in which they are separated from each other. By controlling the quantify of concrete to be cast in each recessed part 11, the tread steps 5 are finished in a desired prescribed rise size and a tread surface size. Both upper end molding surfaces 12, 13 of the recessed part 11 are used to the upper limit, concrete is placed to both upper end surfaces PO of each recessed part 11, the upper end of the concrete is leveled to be a plane which nearly coincides with the upper end surface of the recessed part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a precast concrete staircase.

[0002]

2. Description of the Related Art Precast concrete stairs are convenient when constructing a reinforced concrete middle-rise or high-rise building. The aim is to improve the efficiency of construction work on site.

As shown in FIG. 1, the basic structure of a precast concrete staircase is a triangular cross-section consisting of a stair floor plate 1 extending diagonally upward, a tread surface 3 and a riser surface 4 formed in a sawtooth shape thereon. It comprises a step portion 5 having a shape. It goes without saying that the tread dimensions and riser dimensions of such precast concrete stairs conform to the Japanese Industrial Standards at a minimum, but differ from building to building depending on the height of the building and the size of the stairs installation location. It is a thing. That is, on the basis of the height from the floor of the lower floor to the floor of the upper floor or the floor from the landing to the floors of the upper and lower floors and the area of the installation place, the stair height H, the stair length L and the number of steps for each building and The tread dimensions S and the rise dimension D are determined.

[0004] As a method of manufacturing the precast concrete stairs as described above, conventionally, each tread surface, the riser surface and the stair floor plate portion are manufactured using a formwork that can be integrally formed at a time.

Another manufacturing method is disclosed in Japanese Unexamined Patent Publication No.
As described in Japanese Patent No. 5559, a step portion having a triangular cross section having a tread surface and a riser surface is first formed by a V-shaped cross section form, and then, separately from the step portion, a flat portion for forming a stair floor plate portion. There is a manufacturing method in which a formwork is installed, concrete is poured into the side formwork, and before the hardening, the steps having the triangular cross-section are placed in parallel on the concrete for the stair floor plate to be integrated.

[0006]

As described above, in the former method, a single formwork is used to simultaneously form a stair floor plate portion and a step portion having a triangular cross section composed of each tread surface and a riser surface. As the size increases, the processing and production of the formwork become complicated, and the production cost is high.

[0007] In addition, only one type of staircase with dimensional specifications can be manufactured. In other words, the kick-up dimensions and the like differ from building to building due to differences in the floor height and installation area of the building, so if the above-mentioned three-part molding frame is manufactured with specifications suitable for one building, For another building, it has to be rebuilt from the beginning, and the cost of the formwork is high, and the product cost of the precast concrete stairs is rebounding.

In the latter method in which the step portion is separated from the stair floor plate portion and formed first, each step portion can be formed neatly. However, the latter publication describes only a method of forming a step portion having one type of dimension using one step portion mold.

[0009] Further, when integrated with the stair floor plate portion, concrete molding of the floor plate portion is started with a flat formwork, and in the middle thereof, a stepped triangular shape is formed on the still soft concrete for the floor plate portion before hardening. Is a method of arranging the steps in parallel, it is difficult to stably place each step at an accurate position in a building site.

[0010]

According to the first aspect of the present invention,
A mold formed by arranging a plurality of recesses for concrete molding having an upwardly open V-shaped cross-section having a molding surface for a tread for molding a tread surface of a stair and a molding surface for a riser surface for molding a riser surface. , Concrete is cast, and the height and inclination of the upper surface of the concrete in the recess are adjusted to form a predetermined number of steps having a triangular cross section in which the dimensions of the tread and the rise are finished to a desired size, and then the stairs are formed. A method for manufacturing a concrete staircase, characterized in that the predetermined number of steps are integrally joined in a sawtooth shape by molding the floorboard portion into concrete.

According to a second aspect of the present invention, in the method for manufacturing a precast concrete staircase according to the first aspect, a predetermined number of steps having a triangular cross-section are joined so that a joint surface between the tread surface and the riser surface faces upward. As well as being arranged adjacently on the same horizontal plane, a side formwork for forming a stair floor plate portion protruding upward from the joint surface around the step portion is installed,
A method of manufacturing a precast concrete staircase, characterized by integrating concrete in a side formwork and a step portion by driving concrete into an upper side of a joint surface.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A precast concrete staircase shown in FIG. 6 has a staircase floor plate 1 installed diagonally and a tread surface 3.
And a precast concrete staircase comprising a plurality of step portions 5 comprising a riser surface 4 and a stair length of Lmax,
Stair height is Hmax, tread width is Smax, and rise size is Dmax
And Here, the reason why max is added to each dimension is that the step portion having the maximum size that can be manufactured by the step portion forming mold 10 shown in FIG. 2 is manufactured.

FIG. 2 shows a manufacturing process of the step portion 5 constituting the precast concrete staircase of FIG. 6, and a mold 10 for forming the step portion is provided with a plurality of V-shaped concave portions 11 which are open upwards. One surface of each recess 11 is a tread forming surface 12 for forming the tread surface into concrete, and the other surface is a riser forming surface 13 for forming the riser surface into concrete. The angle θ1 between the two molding surfaces 12, 13 is
The angle is set to be smaller than 90 ° (for example, about 80 ° to 85 °) in order to secure the rise space of the stairs.

A plurality of steps 5 having a triangular cross section are formed simultaneously and separately from each other (separated state) by driving concrete into each recess 11.

By adjusting the amount of concrete poured into each recess 11, the step portion 5 is finished to a desired rise size and tread size. FIG. 2 shows the maximum utilization of both the molding surfaces 12, 13 of the recess 11. Then, concrete is poured into both upper ends P0 of the concave portions 11, and the upper surface of the concrete is leveled or cut into a plane substantially coincident with the upper end surface of the concave portion 11.

When the concrete is properly dried, anchor bars 15 are inserted into the concrete of each recess 11. The anchor bar 15 has a ring portion 15a at the upper end, and the pin bar 16 is inserted into the ring portion 15a in a skewered manner, and both ends of the pin bar 16 are horizontally positioned at a certain height by a suitable support member. , The projection height of the anchor streaks 15 is kept uniform.

FIG. 3 is an enlarged partial view of FIG. 2 and clarifies each dimension of the step portion 5 to be concrete-molded. That is, from the tread forming surface 12 to the riser forming surface 1
The distance from the upper end P0 to the upper end P0 is the rise dimension Dmax, and the length obtained by subtracting the length of the rise space Q from the width Wmax of the tread forming surface 12 is the tread width Smax. The upper end surface of the concrete in the concave portion 11 serves as a joint surface 6 for joining to the stair floor plate portion.

FIG. 4 shows the completed predetermined number of step portions 5.
Are integrally joined by concrete molding of the stair floor plate. A V-shaped pedestal 1 on a base 24 of a side frame 21 for forming a stair floor plate portion, the slidable in the horizontal direction and the inclination angle about the lower center 0 of rotation being adjustable.
7 are installed in a predetermined number, and each step portion 5 is placed on each receiving stand 17 in the opposite direction. By adjusting the position of the pedestal 17 in the horizontal direction and adjusting the inclination angle of the pedestal 17 about the rotation center 0, the joining surfaces 6 of the step portions 5 are adjacent to each other without any gap, and each joining surface is 6 are aligned on the same horizontal plane, and the positions of the end plate portions 21a and the like of the side mold 21 are adjusted.

The left and right ends of the step portion 5 are aligned on the same vertical plane by the lower half of the side frame 21 as shown in FIG. Further, as shown in FIG. 4, a required number of reinforcing bars 22 for the stair floor plate are arranged, and the reinforcing bars 22 are attached to the end plates 21 of the side formwork 21.
a and the like. At this time, some of the reinforcing bars 22 are inserted into the ring portions 15 a of the anchor bars 15.

Concrete is driven from above into a stair floor plate forming space surrounded by the side plate portion of the side mold 21, the end plate portion 21a of FIG. 4, and the joint surface 6, thereby forming the stair floor plate portion. Thereby, all the step portions 5 and the stair floor plate portion 1 are integrated with concrete. This completes the precast concrete stairs shown in FIG.

The precast concrete staircase shown in FIG. 10 has the same basic structure as the staircase shown in FIG. 6, except that each dimension is changed so as to be adapted to another building. The height Hn, the tread width Sn, and the rise dimension Dn are smaller than those of the steps shown in FIG.

FIG. 7 shows the steps of manufacturing the step portion 5 constituting the precast concrete staircase of FIG. 10. The same mold 10 as that used in FIG. 2 is used for forming the step portion. By adjusting the amount of concrete to be poured into the concave portion 11 and the inclination of the upper surface using the ruler 23,
The step portion 5 having a desired size is manufactured.

In FIG. 8 showing an enlarged partial view of FIG. 7, a ruler 23 having an L-shaped cross section is placed on the upper end (corner) P0 of the concave portion 11, and the ruler 23 is placed on concrete in accordance with the edges P1 and P2. Adjust the height and slope of the end face. That is, the length B of one arm of the ruler 23 is set such that the distance from the tread forming surface 12 to one end P1 of the ruler 23 is the kick-up dimension Dn.
The ruler 23 is set so that the length Wn from the other end P2 of the ruler to the lower end P3 of the concave portion 11 has a dimension obtained by adding the width (falling width) of the tuck-in space to the tread width Sn. The length B2 of the other arm is set. The ruler 23 is provided with various dimensions or an adjustable arm length so that various rise dimensions and treads can be formed, and the length of the arm can be adjusted according to the floor height and stair length of the building. It can be used selectively or the arm length can be adjusted.

Concrete is poured into each of the recesses 11 and the upper surface of the concrete is leveled or scraped with a spatula or the like, so that the upper surface of the ruler 23 is formed into a flat upper surface along the surface connecting the edges P1, P2, and , Also slope. On this occasion,
Since the concrete itself has a relatively large viscosity, even if an inclined surface is formed, its shape can be sufficiently maintained. If it is soft, the upper end surface is shaved in a somewhat dry state to form an inclined surface as shown in FIG.

When the concrete has dried properly, FIG.
Similarly, the anchor 15 is inserted into the concrete of each recess 11 of FIG. The anchor bar 15 may be inserted at right angles to the upper end surface of the concrete, or may be inserted in a vertical posture. Also, as shown in FIG.
Insert the hairpin 16 in a skewered manner into the hairpin 16
Are held at a constant height in a horizontal posture, so that the protrusion heights of the anchor streaks 15 are made uniform.

FIG. 9 shows a step of integrally joining a predetermined number of steps 5 manufactured in FIGS. 7 and 8 by concrete molding of a stair floor plate. As in the case of FIG. 4,
A predetermined number of step portions 5 are placed on the V-shaped pedestals 17 such that the joint surfaces 6 face upward, and the position of the pedestals 17 is slid in the horizontal direction and rotated about the rotation center 0 at the lower end. By adjusting the inclination angle by dynamic adjustment, the joining surfaces 6 of the step portions 5 are adjacent to each other without any gap, and the joining surfaces 6 are aligned on the same horizontal plane.

Around the step portion 5, a side mold 21 for forming a stair floor plate projecting upward from the joint surface 6 is installed, and a required number of reinforcing bars 22 for the stair floor plate are arranged. 21 and supported by the end plate 21a. At this time, some of the reinforcing bars 22 are inserted into the ring portions 15 a of the anchor bars 15.

Concrete is poured into the side formwork 21 from above to form the stair floor part 1, so that all the steps 5 and the stair floor part 1 are integrated with concrete. As a result, a precast concrete stair having the dimensions shown in FIG. 10 is completed.

As described above, the step portion 5 is formed first in a separate step from the stair floor plate portion 1 and is manufactured separately from each other, so that one type of step portion forming mold 10 and stair floor plate portion forming The preform concrete stairs having various dimensions, such as the precast concrete stairs having dimensions as shown in FIG. 6 and the precast concrete stairs having dimensions as shown in FIG.

FIG. 11 shows a concrete molding method in which only the kick-up dimension Dn is changed. A ruler 27 for regulating only the length of the riser forming surface 13 is used, and an edge P4 of the ruler 27 is used. The upper end surface of the concrete is formed along a surface connecting the upper edge P1 of the tread forming surface 12 and the tread forming surface 12.

[0031]

FIG. 12 shows a mold 10 for forming a step portion.
A horizontal attachment attachment surface 30 having a fixed width is formed between the upper ends of the V-shaped concave portions 11, and various attachments 31, 32, 33 having different heights are formed on the attachment surface 30. The length of the tread forming surface 12 and the riser forming surface 13 can be appropriately extended by replacement and mounting. Attachments 31, 3
Reference numerals 2 and 33 denote triangular attachments 31 each having a slope that is flush with the tread forming surface 12 and the riser forming surface 13, respectively, and are flush with the tread forming surface 12 and the riser forming surface 13. Trapezoidal attachments 32 and 33 having various heights lower than the above-mentioned triangular attachment and having a slanted surface are used. The attachments 30 are interchangeably mounted on the mounting surface 30 using bolts 35. ing.

FIG. 13 shows another method of arranging the step portions 5 adjacent to each other and another supporting method. The horizontal cross pipe 41 is moved horizontally in the lower half of the side frame 21 for forming the stair floor plate. Adjustably installed, each cross pipe 41
Thereby, the tread surface 3 of each step portion 5 is abutted and supported. On the other hand, each step portion 5 is sandwiched between the tread surface 3 and the joint surface 6 and has a corner portion cut off, and the leading end portion of the step portion 5 adjacent to the cut-off surface 43 on the rise surface side is overlapped. With this structure, the joining surfaces 6 can be simply arranged on the same plane and arranged adjacent to each other without providing the receiving base 17 as shown in FIG. 4 or FIG.

The concrete in the present invention is
Needless to say, concrete materials other than ordinary concrete include concrete materials in which various reinforcing materials are mixed in concrete, such as glass fiber concrete.

The precast concrete staircase manufactured according to the present invention is not limited to a staircase having a basic shape comprising a step portion and a stair floor plate as shown in FIG. 1, but a staircase integrally forming a handrail or a landing. Can also be applied.

[0035]

As described above, according to the present invention,
A step portion 5 having a triangular cross section that forms the tread surface 3 and the riser surface 4 is formed of concrete first, and then the stair floor plate portion 1 is concrete-formed to integrally connect the step portion 5 in a sawtooth shape. In the step of forming the tread 3, the tread forming surface 12 and the riser forming surface 1 are formed.
When the concrete is driven into a formwork 10 having a plurality of concave portions 11 for concrete molding having an upwardly open V-shaped cross-section and having an upwardly open V-shaped section, by adjusting the height and inclination of the upper surface of the concrete, Since the dimensions of the tread surface 3 and the riser are changed to desired dimensions, a method of simultaneously forming the floor plate portion and the triangular cross-sectional portion including the tread surface and the riser surface by one large formwork as in the related art. In addition to the fact that the size of the form can be reduced and the form and processing of the form can be facilitated, various forms corresponding to the floor height and the like of the building can be provided by the form 10 for forming one step portion. It is possible to manufacture stairs having a kick-up dimension and a tread dimension, so that the cost of a mold for manufacturing the stairs can be significantly reduced.

According to the second aspect of the present invention, a predetermined number of steps 5 hardened by concrete molding are formed so that the joint surface 6 between the tread surface 3 and the riser surface 4 faces upward and on the same horizontal plane. The stair floor plate portion is concrete-formed by the floor frame forming mold 21 above the joint surface 6, so that when the stair floor plate portion is concrete-formed, each step portion 5 which is a solid material is formed. Can be accurately and stably arranged in a predetermined positional relationship, and the joining surface 6 can be accurately aligned on the same horizontal plane. In addition, since the step portion 5 is arranged upside down and concrete is poured into the step portion and concrete is formed on the stair floor plate portion, there is no obstacle to pouring concrete from above, and the concrete placing operation is easy.

[Brief description of the drawings]

FIG. 1 is a perspective view of a precast concrete stair.

FIG. 2 is a longitudinal sectional view of a mold and the like showing a step forming step of a manufacturing method to which the present invention is applied.

FIG. 3 is a partially enlarged view of FIG. 2;

FIG. 4 is a longitudinal sectional view of a side mold and the like showing a step of forming a stair floor plate portion for integrally connecting the step portions formed in FIG. 2;

FIG. 5 is a sectional view taken along line VV of FIG. 4;

FIG. 6 is a longitudinal sectional view of a precast concrete staircase manufactured through the manufacturing steps of FIGS. 2 to 5;

FIG. 7 is a longitudinal sectional view of a mold or the like showing a step of forming a step portion having a dimension different from that of FIG. 2;

FIG. 8 is a partially enlarged view of FIG. 7;

9 is a longitudinal sectional view of a side mold and the like showing a step of forming a stair floor plate portion for integrally joining the step portions formed in FIG. 7;

FIG. 10 is a longitudinal sectional view of a precast concrete staircase manufactured through the manufacturing steps of FIGS. 7 to 9;

FIG. 11 is a longitudinal sectional view of a mold or the like showing a step of forming a step portion having a different size from FIGS. 3 and 8;

FIG. 12 is a longitudinal sectional view showing a modification of the step-forming mold.

FIG. 13 is a longitudinal sectional view showing a modification of a step portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Floor plate for stairs 3 Tread surface 4 Raised surface 10 Forming part for forming step part 11 V-shaped concave part 12 Molded surface for tread surface 13 Molded surface for rise surface

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[Procedure amendment]

[Submission date] March 29, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

[0010]

According to the first aspect of the present invention,
A mold formed by arranging a plurality of recesses for concrete molding having an upwardly open V-shaped cross-section having a molding surface for a tread for molding a tread surface of a stair and a molding surface for a riser surface for molding a riser surface. By adjusting the height and inclination of the concrete upper surface in the recess, the concrete and the stepped portion with a triangular cross section, the dimensions of the treads and the rise are finished to the desired dimensions, are separated from each other by a predetermined number. A method of manufacturing a concrete staircase, comprising forming the stair floor plate portion into concrete, and thereafter integrally bonding the predetermined number of steps in a saw-tooth shape.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Masahiro Nonogami 6-8-10 Fukushima, Fukushima-ku, Osaka-shi, Osaka

Claims (2)

[Claims] 1. A concrete forming recess having a V-shaped cross section having an upwardly open V-shape and having a tread forming surface for forming a stair tread surface and a riser forming surface for forming a riser surface. Concrete is poured into a formwork, and the height and inclination of the concrete upper surface in the recess are adjusted to form the specified number of steps with a triangular cross section with the dimensions of the tread and riser to the desired dimensions. Then, the predetermined number of step portions are integrally connected in a saw-tooth shape by forming the stair floor portion into concrete, and thereafter, a method of manufacturing a concrete staircase. 2. A method for manufacturing a precast concrete staircase according to claim 1, wherein a predetermined number of step portions having a triangular cross section are formed so that a joint surface between the tread surface and the riser surface faces upward, and the same horizontal plane. A side form for stair floor plate forming is provided around the step and protruding upward from the joint surface, and concrete is placed inside the side form and above the joint surface. A method for manufacturing a precast concrete staircase, wherein a stair floor plate portion is integrated with a step portion by driving.