JPH03275851A - Composite hollow slab - Google Patents

Abstract

PURPOSE:To heighten the height of a ceiling and to make it possible to apply also to a building structure with a large span by laying PC cable insertion members between a plurality of PS hollow beam units, and burying them into cast-in-place concrete. CONSTITUTION:A plurality of PS hollow beams 11... are arranged in a row by bringing the outside surfaces into contact with each other, and they are bound with a fastening belt, etc., to form PS hollow beam units 10.... After that, a plurality of PS hollow beam units 10... are spread and arranged, and necessary PC insertion members 20 and 20 are laid between them. Then, cast-in- place concretes 30 and 30 are placed, PS hollow beam units 11... and PC cable insertion members 20 and 20 are buried thereinto, and a composite hollow slab S having a space inside the slab is formed. According to the constitution, the thickness of the cast-in-place concretes 30 and 30 can be formed in thin and, at the same time, the covering can be made large.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a composite hollow slab having an internal space and constituting the floor of an architectural structure, and is particularly applicable to large spaces such as offices and research institutes. and the load capacity is 300 to 500
The present invention relates to a composite hollow slab suitable for use in architectural structures requiring a weight of 100 kg/m''.

[Prior Art] Conventionally, after assembling large beams and small beams, a slab was constructed by pouring cast-in-place concrete.

However, since such slabs are solid, they have the drawback of being heavy and making it impossible to increase the floor thickness.

Therefore, hollow slabs that reduce weight by providing a space inside the slab have been developed and implemented.

The hollow slab has a space in the center of the slab thickness, and slabs such as "Spancrete" made of PC (precast concrete) and "Quinaspan" (product name) shown in Figure 8 are being provided. .

[Problems to be Solved by the Invention] Incidentally, when constructing a floor using a hollow slab such as spancrete, cast-in-place concrete had to be placed. This is to effectively transmit horizontal force to columns, beams, and load-bearing walls when the building structure receives horizontal force. Nowadays, when CD pipes are often used for electrical piping, when constructing floors using Sbank IJ-to, etc., there is no space for wiring such as electrical cables, so such CD pipes are cast on-site and hardened with concrete. It had to be buried inside the body.

Therefore, there was a problem that (1) the thickness of cast-in-place concrete became thicker and the ceiling height became lower (this problem becomes more noticeable when the CD pipes 2 intersect as shown in FIG. 9). In the figure, reference numeral 3 indicates a hardened cast-in-place concrete body.

■Also, since the cover of cast-in-place concrete becomes smaller, span 1. There was a problem in that hollow slabs such as spancrete could not be used for architectural structures with a diameter of 0.0 m or more.

The present invention has been made in view of such problems, and
The objective is to provide a composite hollow slab that can increase the ceiling height compared to the prior art and can be applied to architectural structures requiring large spans.

[Means for Solving the Problems] The gist of the present invention is to provide a composite hollow slab having an internal space and constituting the floor of an architectural structure, comprising a plurality of prestressed concrete hollow beams (hereinafter referred to as PS hollow beams). ) and a fastener for fastening the plurality of PS hollow beams, a PC cable insertion member interposed between the PS hollow beam units, and the PS hollow beam unit and the PC cable insertion member. The present invention resides in a composite hollow slab characterized by being equipped with a cast-in-place concrete hardened body that is buried.

[Function] The PC cable insertion member encloses a cable such as an electric wire. Therefore, it is not necessary to bury the PC cable in cast-in-place concrete. As a result, the thickness of cast-in-place concrete can be made thinner than in the prior art.

However, according to the present invention, it is possible to increase the ceiling height compared to the conventional technology. Also, since the cover of cast-in-place concrete can be increased, it is possible to create a building with a larger span compared to the conventional technology. It can also be applied to structures.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in this example are not intended to limit the scope of this invention to only those, unless specifically stated. It's just an illustrative example.

First, the structure of the composite hollow slab according to this embodiment will be explained using FIGS. 1 to 3.

As shown in Fig. 1, the composite hollow slab S is made up of five PS (prestressed concrete) hollow beam units to
, two PC cable insertion members 20 , and a hardened cast-in-place concrete body 30 . In addition, in the figure, the code|symbol 40 is a girder.

The PS hollow beam unit 10, as shown in FIG.
It consists of three PS hollow beams 11 and a fastener 12 that fastens the three PS hollow beams 11.

The PS hollow beam 11 is made of PC (precast concrete) and has an octagonal outer contour and a circular inner contour when viewed in cross section. Furthermore, in this example,
By providing unevenness in the formwork, the PS hollow beam 1
The outer surface of 1 is provided with unevenness. Further, both ends of the PS hollow beam 11 are closed with end aphasia concrete 13, as shown in FIG. The end aphasia concrete 13 is provided from a portion 3 to 5 cm from the end of the PS hollow beam 11. Note that the PS hollow beam 11 may be manufactured by the same method as for PC piles and the like. In the figure, reference numeral 14 is a tendon material.

The fastener 12 consists of a steel rod 12a having male screws at both ends, and nuts I, 2b.

The method of using the fastener 12 is as shown in FIG. 2, by arranging the three PS hollow beams 11 so that their outer surfaces 11a are in contact with each other, and
The three PS hollow beams 11 are inserted by penetrating the steel rod 12a from the outer surface 11a of the - PS hollow beam 11 located at both edges of 0 to the outer surface 11a of the other PS hollow beam 11. It is connected. Note that the outer surface 11a of the PS hollow beam 11 has a hole 11 for storing the nut 12b.
b. In the figure, numeral 21 is a tendon.

The PC cable insertion member 20 has a U-shape in cross-sectional view, and the PC cable insertion member 20 has a U-shaped opening facing downward.
It is made of prestressed concrete and is interposed between S hollow beam units 10.

The cast-in-place concrete hardened body 30 is hardened concrete poured on-site, and the PS
hollow beam unit) 10 and the PC cable insertion member 20
It is constructed by embedding.

Next, the method of constructing the composite hollow slab S will be explained using FIGS. 4 and 5.

First, the PS hollow beam unit 10 manufactured in a factory
Then, the PC cable insertion member 20 is installed between the girders 50, and the bottom formwork (not shown) of the girder 40 is assembled.
Perform the specified reinforcement arrangement.

Next, the formwork will be supported and cast-in-place concrete will be placed.

After the cast-in-place concrete has hardened, the formwork is removed, and the composite hollow slab S can be constructed as shown in FIGS. 4 and 5.

In addition, in this embodiment, the PS hollow beam unit 1
0 was assembled in a factory, or the scope of the present invention is not intended to be limited thereto; the present invention may also be assembled in the field.

Next, the operation of the composite hollow slab S constructed as above will be explained.

The PC cable insertion member 20 includes a cable such as an electric wire.

Said end aphasia conc! J-) 13 serves to increase the shearing force of the PS hollow beam 11 and prevent cast-in-place concrete from entering the PS hollow beam 11.

Next, the effects of the composite hollow slab S configured as above will be explained.

Since the PC cable insertion member 20 according to the present invention does not require burying the cable in cast-in-place concrete,
According to the present invention, the thickness of the hardened cast-in-place concrete body 30 can be made thinner than in the prior art.

As a result, the ceiling height can be increased compared to the conventional technology.

Furthermore, since the cover of cast-in-place concrete can be increased, it can also be applied to architectural structures having larger spans than conventional techniques. To explain specifically (the PC hollow beam is 300φ P as shown in Fig.
C pile), the height of the PS hollow beam 11 is 300 mm, its wall thickness is 60 mm, the floor thickness of the cast-in-place concrete 1 and hardened body 3''O is 100 mm, and the cast-in-place concrete is hardened. The bulk specific gravity of the body 30 is 2.4 (t/m'
), then the dead weight per unit length of the PS hollow beam 11 WDLP% The dead weight of the cast-in-place concrete hardened body 3o w
ot, c and working load WL are respectively W I) LP
-(0,3'-0,18")π/4X2.4#0010
9t/mW o+, c-(Q, 3x O, 25-0,
3″yr /8) X 2.4!-i 0.098t
/mW+, = 0.15t/m' x 0.3x1. ,
0=0.045t/m, and therefore the load W during construction is w=WDLP+WDLC+WL=0.25t/m.

On the other hand, if the PS hollow beam 1.1 is treated as a simple beam with a span of Q, M a = 1/8X w (2' tm ), and the crack bending moment l of 0 types of PC pile 300φX60
' M c is M c = 4. It is OOtm.

Here, Q when M is kept below 4,OOtm. a
x is Q max≦(4,OX8−;0.25)”=
It will be 11.3m.

Therefore, according to the composite hollow slab S according to this example, 10
It can also be used in spans of m or more. By providing one intermediate support, the span can be further increased. Further, from the above calculation results, it is possible to sufficiently cope with a load of 300 to 500 kg/m''.

Furthermore, the space created by the PC cable insertion member 20 can be used as a tact or as a space for a fluorescent lamp, as shown by the dotted line in FIG.

Furthermore, since the PS hollow beam 11 has an octagonal outer contour in cross-sectional view, it can be easily fastened with the fastener 12.

Moreover, since mass production is possible at a PC pile factory, the composite hollow slab S can be manufactured at a very low cost compared to other hollow slab construction methods.

In addition, since the outer surface 11b of the PS hollow beam 11 is provided with unevenness, the cast-in-place concrete hardened body 30 and the PS hollow beam 1 are formed with unevenness compared to a case where such unevenness is not provided.
1 can be improved.

In addition, in this embodiment, the P'S hollow beam unit 1
0 is made up of three PS hollow beams 11, but this is not intended to limit the scope of the present invention, and the present invention may include other numbers of PS hollow beams 11, such as 1, 2, 4, etc. , the number can be set to a suitable number for implementing the present invention.

Furthermore, although the outer contour of the PS hollow beam 11 in a cross-sectional view is octagonal, this is not intended to limit the scope of the present invention; other shapes such as triangular, triangular,
The shape may be a rectangular, hexagonal or other polygonal shape, a circular shape, an elliptical shape, or the like, which is suitable for carrying out the present invention.

Further, although the inner contour of the PS hollow beam 11 in a cross-sectional view is circular, this is not intended to limit the scope of the present invention, and the present invention may have other shapes, such as triangular, 4
The shape may be a rectangular shape, a hexagonal shape or other polygonal shape, or an elliptical shape, which is suitable for carrying out the present invention.

Further, the fastener 12 is connected to the steel rod 1 as shown in FIG.
2a and the nut 12b, however, the scope of the present invention is not limited thereto, and the present invention includes other components such as those shown in FIGS. 6 and 7. Any suitable method can be used to implement the method.

The fastener 15 shown in FIG. 6 and FIG.
a, fastener 15b, washer 15C, and nut 1
5d. The tightening belt 15a has two loose holes 15a1 at each end, and two through holes 15a at the center.

The fastener 15b is made up of a steel plate 15b that is rectangular in plan view, and bolts 1.5 b t that are provided at both ends of the steel plate 15 b. The method of using such a fastener 15 is to arrange the three PS hollow beams 11 so that their outer surfaces 11a are in contact with each other, and The tightening belt 15a on the side surface 11a
The fastener 1.5b is passed through each loose hole 15a1 to the through hole 5b, and fastened using a washer 15C and a nut 15d.

Furthermore, although the PC cable insertion member 20 has a U-shape in cross-sectional view, this is not intended to limit the scope of the present invention, and the present invention is intended to be described as a U-shaped member suitable for carrying out the present invention. It can be any shape.

In addition, the PS hollow beam 1 is provided with end aphasia concrete 13 at both ends thereof, but it is not intended to limit the scope of the present invention to this, and it is not necessary to provide it in the present invention. In that case, a cap will be provided to prevent the flow of post-cast concrete.

[Effects of the Invention] The present invention, configured as described above, produces the following effects.

Since the PC cable insertion member according to the present invention does not require burying the cable in cast-in-place concrete, according to the present invention, the thickness of cast-in-place concrete can be made thinner than in the prior art. As a result, the ceiling height can be increased compared to the conventional technology. Furthermore, since the cover of cast-in-place concrete can be increased, it can also be applied to architectural structures having larger spans than conventional techniques.

[Brief explanation of drawings]

Figures 1 to 6 show one embodiment of the present invention. Figure 1 is a perspective view of a composite hollow slab, Figure 2 is an enlarged view of Figure 1, and Figure 3 is a PS hollow beam end. FIG. 4 is a plan view of a standard floor constructed using a composite hollow slab, FIG. 5 is a cross-sectional view of FIG. 4, and FIGS. 6 and 7 show other examples of fasteners. 6 is a perspective view of a fastener, FIG. 7 is a sectional view of a PS hollow beam unit bundled by a fastener, and FIGS. 8 and 9 are conventional examples. The figure is a cross-sectional view of spancrete, and FIG. 9 is a cross-sectional view of a slab formed by embedding CD pipes in cast-in-place concrete. S...Composite hollow slab, 10...PS
Hollow beam unit, 11...PS hollow beam, 12.
... Fastener, 14.21 ... Tensile material, 15
...... Fastener, 20... PC cable insertion member, 30... Cast-in-place hardened concrete, 40.50... Large beam.

Claims (1)

[Claims] A composite hollow slab having a space inside and constituting the floor of a building structure, comprising a plurality of PS hollow beams and a fastener for fastening the plurality of PS hollow beams; A composite hollow slab comprising a PC cable insertion member interposed between hollow beam units, and a cast-in-place concrete hardened body in which the PS hollow beam unit and the PC cable insertion member are buried.