JPH0522017B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a precast concrete member formed by integrating a beam member and a wall member, and particularly relates to a precast concrete member in which an opening is formed in the wall member. The present invention also relates to a precast concrete member whose shear strength does not suddenly decrease.

"Prior art and its problems" Walls installed in building structures play a role in improving the shear strength of the building structure if they are fixed to columns and beams, and also function as load-bearing walls such as columns and beams. It also plays the role of reducing the horizontal force acting on the Therefore, by constructing the frame of the building structure using the load-bearing walls, it is also possible to reduce the cross sections of columns and beams as much as possible. In many cases, these load-bearing walls are integrated with beams fixed above and below them, and if they are made of precast concrete, the on-site construction work of the load-bearing walls can be streamlined. promoted.

Here, in a building structure provided with the above-mentioned load-bearing wall, if an opening is formed in the load-bearing wall, there is a possibility that the shear strength of the upper and lower beams may decrease rapidly. For this reason, it is possible to reduce the shearing force that enters the beam by making the wall in the area with the opening a non-load-bearing wall and cutting the edge between the wall and the beam, or Measures have been taken to reinforce the shear strength by placing shear reinforcing bars densely in the upper and lower (mainly upper) parts. However, each of the above-mentioned measures leads to problems such as an increase in the cross section of the beam and an increase in the beam's own weight.In addition, since the structure of the area around the opening is different from that of the entire building structure, it is difficult to perform reinforcement work and concrete pouring. There was a risk that the product would be unreliable. This also applies when the wall is not a load-bearing wall.

This invention was made in view of the above-mentioned problems, and in a precast concrete member in which a wall member and a beam member are integrally formed and an opening is formed in the wall member, the cross section of the member increases, and the member's own weight increases. The problem is how to create a precast concrete member that can reliably provide structural reinforcement without causing an increase in .

``Means for Solving the Problems'' Therefore, the present invention provides a concrete beam member constructed between a pair of column members, and a concrete wall member placed either above or below this beam member. When constructing an integrated precast concrete member, a beam main reinforcement extending along the longitudinal direction is provided inside the beam member, and a part of the wall member is notched. forming an opening, and further arranging at least a part of the main beam reinforcement of the beam member so as to intersect with each other in an X-shape at a portion located either above or below the opening of the wall member. It solves the problem.

"Function" In this invention, at least a part of the main beam reinforcement of the beam member located either above or below the opening formed in the wall member of the precast concrete member has an X-shaped reinforcement arrangement. As a result, the toughness of the beam member in this area is improved and the shear strength is reinforced. Moreover, since only a part of the main beam reinforcement of the beam portion is arranged in an X-shape, the shear strength can be reinforced without increasing the cross section of the member or the weight of the member.

"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 3 are diagrams showing a precast concrete member which is an embodiment of the present invention, and reference numeral 1 in the figures indicates the entire precast concrete (hereinafter simply referred to as PC) member.
As shown in FIGS. 4 to 8, this PC member 1 is installed between a pair of reinforced concrete column members 2 erected within a building (architectural structure) A.

The PC member 1 includes a concrete beam member 3 constructed between the column members 2 and 2, and a concrete wall formed at the lower end of the beam member 3 and extending along the longitudinal direction of the beam member 3. The member 4 is constructed by being precast integrally in advance at a factory or the like. Both ends of the beam member 3 extend horizontally from both ends of the wall member 4, that is, the lower part of the extending portion of the beam member 3 is the opening 5 of the wall member 4,
It becomes 5.

Inside the beam member 3, as shown in FIGS. 3 to 7, main beam reinforcements 6, 6, . . . extending along its longitudinal direction are arranged. This beam main reinforcement 6,
6,... are parallel main bars 6a, 6a,... and X-shaped main bars 6
b, 6b,..., and the parallel main reinforcements 6a,
6a, . . . are respectively arranged at four corners of the cross section of the beam member 3 so as to be parallel to the longitudinal direction thereof. On the other hand, the X-shaped main reinforcements 6b, 6b,...
In the portion located above the openings 5, 5,
They cross each other in an X-shape across a virtual vertical plane P along the longitudinal direction of the beam member 3, and are parallel to the longitudinal direction of the beam member 3 in other parts, that is, in the part located above the wall member 4. They are arranged in two pairs. And these main bars 6 (6a, 6b),
Both ends of ... are projected from both end surfaces of the beam member 3, and the parallel main reinforcements 6a, 6a, ... extend parallel to the longitudinal direction of the beam member 3, while the X-shaped main reinforcements 6b, 6b,
... are once bent in the horizontal direction, and their tips are further bent up and down to form L-shaped anchors 7, 8,
...is being formed. In addition, instead of these L-shaped anchors 7, 8, . . . , the shape may be a U-shaped anchor.

There are two types of arrangement methods for these X-shaped main reinforcements 6b, 6b,..., namely, as shown in FIG. 6b is the virtual vertical plane P
As shown in FIG. There is a type in which the X-shaped main reinforcement 6b is located on the left side of the virtual vertical plane P, and the X-shaped main reinforcement 6b located on the lower end side is located on the right side (hereinafter referred to as type 2), and both have a mirror-symmetrical relationship. . Note that the symbols 9, 9, . . . are ribs wound around the parallel main reinforcements 6a, 6a, .

On the other hand, grid reinforcing bars (not shown) extending in the horizontal and vertical directions are buried in the wall member 4, and among these reinforcing bars extending in the horizontal and vertical directions, vertical reinforcing bars extending in the vertical direction are The lower ends of the striations protrude from the lower end surface of the wall member 4. Also, inside the column member 2, there is a column main reinforcement 1 extending in the vertical direction.
0, 10, . . . are arranged along the periphery of the column member 2, and a band reinforcement 11 is wound around these column main reinforcements 10, 10, .

Next, a method of installing the PC member 1 having the above structure between the column members 2 will be explained.

First, the PC member 1 is positioned between the column members 2, 2, which have been concreted up to the bottom of the beam, or between the column members 2, 2 using an appropriate frame, and the column main reinforcements 10, 10, . . . and the L-shaped anchors 8, 9,
... or by using other auxiliary reinforcements etc. to arrange reinforcement at the joint part (intersection of columns and beams), arrange formwork around this joint part, and pour concrete inside. Set up Building A is constructed by doing this sequentially, but for the PC members 1, 1 that are connected horizontally across the joint, type 1 PC member 1 and type 2 PC member 1 are alternately used. used for. That is, with such a configuration, the L-shaped anchors 8, 8 on the X-shaped main reinforcements 6b, 6b side protruding from the ends of the beam members 3, 3 of the left and right PC members 1, 1 are adjacent to each other. Since the distance between these anchors 8, 8 is extremely narrow, the connection becomes easy. At the same time, within this Shiguchi section,
L on the parallel main reinforcement 6a side from the left and right PC members 1, 1
Since the character-shaped anchor 9 and the L-shaped space 8 on the X-shaped main reinforcement 6b side do not interfere, after one PC member 1 is installed, it is possible to drop the other PC member 1 from above, and the installation Work becomes easier.

The vertical reinforcements protruding from the lower end surface of the wall member 4 of the PC member 1 may be intersected with the rebars protruding from the floor slab on the floor below, and concrete may be poured at this intersection to integrate them. etc., it may be jointed to the reinforcing bars of a beam or floor slab, or to a plate embedded in the beam in advance, or furthermore, it may be in a state where the edges are cut without being integrated or jointed.

In the PC member 1 having the above configuration, the main beam reinforcements 6, 6, ... of the beam member 3 in the portion corresponding to the upper part of the openings 5, 5 formed in the wall member 4 are partially (X-shaped) Since the main reinforcing bars 6b) are arranged in an X-shape, the toughness of the beam member 3 in this area is improved, and the reduction in shear strength due to the provision of the openings 5 is reinforced. Therefore, this PC member 1 can be used as a load-bearing wall, and there is no need to construct only the portion where the opening is provided as a non-load-bearing wall structure as in the past. Moreover, since only a portion of the beam main reinforcements 6, 6 of the beam member 3 are arranged in an X-shape, the shear strength can be reinforced without increasing the cross section of the member or the weight of the member. The X-shaped reinforcement can be placed at any position within the beam member 3, so that it can flexibly correspond to the plan of the flexible building A. Therefore, according to the present invention, it is possible to realize a precast concrete member that can reliably perform structural reinforcement without increasing the cross section of the member or increasing the member's own weight.

In particular, this PC member 1 has a load-bearing wall structure in which a shear-reinforced beam member 3 and a wall member 4 are integrated. By appropriately selecting the striation method etc., it is possible to arbitrarily adjust the rigidity of the entire PC member 1. This can also be arbitrarily adjusted by the method of fixing the lower end of the wall member 4 to the floor slab or the like. Furthermore, since the beam member 3 and the wall member 4 are integrally formed, it goes without saying that the workability on site is very good.

Note that the precast concrete member of the present invention is not limited to its shape, dimensions, or application method to the above embodiments, and various modifications are possible. As an example, the beam main reinforcements 6, 6,... of the beam member 3 are
is not limited to a configuration in which only one level of reinforcement is arranged in the height direction as in the above embodiment, but, for example, two levels are arranged in the height direction.
It may also be configured with stepped reinforcement. In addition, wall member 4
The position of the opening 5 formed in the opening 5 is arbitrary as described above, and it may be provided only at one end as shown in FIG. 9, or it may be provided in the center as shown in FIG. . In this case, as a matter of course, some of the main beam reinforcements 6, 6, . . . of the beam member 3 located above the opening 5 are formed into X-shaped back reinforcements.

Here, if the openings 5 are not provided at both ends of the wall member 4 as shown in FIG. 10, it is necessary to consider the connection between both ends of the wall member 4 and the column members 2, 2. . However, this may also be done by the same method as the method of joining the vertical bars protruding from the lower end surface of the wall member 4 and the floor slab reinforcing bars.

Furthermore, the wall member 4 may be provided either above or below the beam member 3. In other words, the PC member 1 shown in FIG. 1 or FIGS. 9 and 10 may be turned upside down.

Furthermore, the beam member 3 is fully formed as in the above embodiment.
The beam member 3 does not have to be a PC, and may be a half-PC beam member 3 with a portion on which cast-in-place concrete is placed. Similarly, the wall member 4 may be a so-called earthquake-resistant wall in which a brace made of iron plates, steel frames, or reinforcing bars is provided inside. However, the joint at this time is a bolt or the like that connects the plate at the end of the brace and the plate embedded in the beam. As a result, PC member 1
Overall rigidity is increased.

"Effects of the Invention" As explained in detail above, according to the present invention, at least a portion of the main beam reinforcement of the beam member located either above or below the opening formed in the wall member is Since the reinforcement is arranged in the form of a mold, the toughness of the beam in this area is improved and the shear strength is reinforced. Therefore, this precast concrete member can be used as a load-bearing wall. Moreover, since only a part of the main beam reinforcement of the beam member is arranged in an X-shape, the shear strength can be reinforced without increasing the cross section of the member or the weight of the member.
Therefore, according to the present invention, it is possible to realize a precast concrete member that can reliably perform structural reinforcement without increasing the cross section of the member or increasing the member's own weight.

[Brief explanation of the drawing]

Figures 1 to 3 are diagrams showing a precast concrete member that is an embodiment of the present invention, in which Figure 1 is a front view, Figure 2 is a side view, and Figure 3 is a circle of Figure 1. Perspective view showing the inside enlarged, No. 4
Figures 8 to 8 are diagrams showing the precast concrete member installed in a building, and Figure 4 is a plan view showing an enlarged view between a pair of column members, and Figure 5 is a diagram showing the precast concrete member installed in a building. is a sectional view taken along line -' in Fig. 4, Fig. 6 is a sectional view taken along line -' in Fig. 4, and Fig. 7 is a sectional view taken along line -' in Fig. 4. , FIG. 8 is a cross-sectional view showing the whole, FIG. 9 is a front view showing a precast concrete member according to another embodiment of the present invention, and FIG. 10 is a front view showing another embodiment. 1... Precast concrete member, 2...
Column member, 3...Beam member, 4...Wall member, 5...Opening, 6...Beam main reinforcement, 6b...X-shaped main reinforcement.

Claims (1)

[Claims] 1. A precast concrete member formed by integrating a concrete beam member installed between a pair of column members and a concrete wall member placed either above or below this beam member. , a beam main reinforcement extending along the longitudinal direction is disposed inside the beam member, and a portion of the wall member is cut out to form an opening, and further, A precast concrete member characterized in that at least a portion of the main beam reinforcements are arranged to intersect with each other in an X-shape at a portion located either above or below the opening of the wall member.