JP5083808B2 - Concrete earthquake-resistant wall floor structure - Google Patents

Description

  The present invention relates to a concrete earthquake-resistant wall floor structure. In the present specification, the “wall-floor structure” refers to a structure that supports the force applied to the frame by a planar structure (wall slab and floorboard) without using beams or columns.

  A structure in which a pillar is eliminated and the frame is composed of a wall, a floor, and a beam is conventionally known. However, since the beam protrudes into the room and disturbs the space, the beam and the floor are further omitted. A constructed structure has been proposed (Patent Document 1).

In this type of structure, in order to improve the strength of the location where the wall and the floor intersect, the applicant has a cross-sectional shape including the intersection of the wall and the floor as viewed from the longitudinal section direction, It has been proposed that a member (wall-floor joint) extending along the wall-floor joint line is manufactured in advance as a high-strength concrete member (Patent Document 2). As shown in FIG. 16, the concrete member has a shape in which a penetration bar is inserted in advance.
JP-A-11-081450 JP-A-2005-220517

  The structure of Patent Document 1 can take a large space in the housing, but does not use columns or beams, so it is necessary to pay sufficient attention to the strength design of the wall and floor slabs. In this regard, Patent Document 2 proposes a method using high-strength concrete in the vicinity of the intersection between the floor and the wall in order to increase the strength of the floor wall structure. However, with this method, it is difficult to use concrete with different strengths for each part of the frame in the field, so a high-strength concrete portion near the intersection is pre-fabricated as a concrete member in advance. This increases the shipping cost of the concrete members from the factory to the site, which is disadvantageous for the construction of condominiums where cost is an important factor.

  Furthermore, in recent studies, slipping due to adhesion failure of reinforcing bars inserted through the floor slab (and wall slab) has become a problem in the wall-floor type structure. Slip due to adhesion failure is a phenomenon in which the adhesion surface is split and the state of sliding is repeatedly repeated, and if this occurs between concrete and reinforcing bars (through reinforcement), the reinforcing force of the reinforcing bars decreases. However, the seismic performance deteriorates. In order to prevent such slipping, it is necessary to reinforce by inserting a large number of lateral restraint bars in the longitudinal direction of the through bar.

    For example, in the concrete member of Patent Document 2, reinforcing bars are inserted in the same direction as the through bars, but in this case, there are the following problems. In other words, each end of the concrete member is joined to the floor slab (or wall slab) concrete that is cast in the field, and then the floor slab (or wall slab) concrete portion adjacent to the concrete member is plastically deformed by seismic force. This is an area that is likely to occur. Then, since it is necessary to splice the reinforcing bar of the concrete member with the concrete reinforcing bar of the floor slab while avoiding this plastic region, it is necessary to increase the protruding length of the reinforcing bar from the concrete member. Therefore, the concrete member including the reinforcing bar becomes bulky and difficult to carry.

  In view of this, the present invention has an object of proposing a structure in which constraining bars are inserted in the vicinity of a crossing portion of a wall and a floor in order to prevent slippage due to adhesion failure in a wall-and-floor type concrete structure cast on site.

The first means is a seismic wall floor structure,
In a concrete earthquake-resistant floor wall structure in which a plurality of concrete wall slabs and floor slabs intersect each other, and through the intersections, bar reinforcements are arranged in the wall slab and floor slab.
The wall slab 4 and the floor slab 6 including the intersection 12 are formed with substantially uniform concrete strength,
A bending reinforcement bar 18 extending in the same direction as the through bar 10 of the floor slab 6 is inserted into at least the intersecting portion 12, and
By extending this bending reinforcement 18 to the portion 14 adjacent to the intersection 12 of the floor slab,
The crossing portion 12 and the adjacent portion 14 are made rigid as a reinforcing region 16 that resists bending deformation and slippage due to adhesion failure of the bar arrangement,
A floor slab portion connected to the reinforcing region 16 is a plastic region 22,
And reposition the plastic hinge h _p the area where the end portion 23 of the plastic region in contact with the reinforcing region,
The end surface 24 of the plastic region was continuously connected to the reinforcing region 16 and was formed by spotting.

    The main theme of this measure is that thick concrete parts such as columns, beams, and hunches are not formed on a part of a concrete frame with uniform concrete strength (preferably on-site concrete frame), or high-strength concrete is not used. But it is to be able to counter seismic forces. In order to achieve this object, in the present means, the position of the plastic hinge is rearranged from the intersection to the center side of the floor span in the continuous wall slab and floor slab structure with uniform strength. Specifically, a reinforcing reinforcement is inserted at the end of the plastic region in contact with the reinforcing region by inserting a bending reinforcing bar along the through bar in the crossing portion and the floor slab portion adjacent to the crossing portion. Is arranged. In this specification, “rearrangement” means that the position of the plastic hinge is moved by extending the bending reinforcing bar from the intersecting portion to the adjacent portion.

  In the present specification, “stiffening” means that the reinforcing region is restrained by a bending reinforcing bar so that plastic deformation (and elastic deformation) is less likely to occur than the surrounding area.

    The “reinforcing region” is a region reinforced by bending reinforcing bars, and is installed at a plurality of positions of the reinforcing bars through the reinforcing areas, thereby preventing a deviation between the reinforcing bars and the concrete. In particular, in the present invention, since the bending reinforcing bar is inserted in the reinforcing region including the intersection with the wall plate, the outer peripheral surface of the reinforcing bar is pressed against the surrounding concrete by the load of the wall in this region, and in this pressed state Since the horizontal displacement is suppressed by the bending reinforcing bar, the adhesion of the through bar to the concrete is improved. This will be described in detail in the section of the embodiment of the invention. The reinforcing region is formed by the intersecting portion and the adjacent portion.

    The “intersection” is a portion where a wall slab and a floor slab that intersect each other overlap, and is a connection point between the wall slab and the floor slab and also a place where the surrounding concrete is most strongly tightened by surrounding concrete. Here, “intersection” means that two linear objects intersect at at least one point, and includes those intersecting in a cross shape as well as those intersecting in a T shape or L shape.

    The “adjacent portion” is a region that protrudes from the intersecting portion, and is a region for moving the generation site of the floor plastic hinge away from the intersecting portion toward the middle portion of the span of the floor slab or wall slab. If the protruding length of the adjacent portion is too short, slippage of the through bar cannot be sufficiently prevented, and if it is too long, there is no point in inserting a bending reinforcing bar near the intersection.

    The “plastic region” is a region that absorbs vibration energy by plastic deformation during an earthquake of a certain level or more. As is well known in the art, a concrete structure can only be elastically deformed by a small shaking, but it will plastically deform to a certain degree of shaking, exhibit energy absorption characteristics, and act to attenuate the shaking of the structure. . FIG. 10 is a graph showing the relationship between the floor average shear force and the interlayer transition angle at that time, and the larger the area of the spindle-shaped loop shown, the higher the energy absorption performance. When the magnitude of the earthquake is large, at the end where the plastic region is continuous with the reinforcing region, plastic deformation occurs over the entire surface and acts as a plastic hinge. One of the important things in the present invention is that the plastic hinge is moved from the intersection with the wall plate to the center side of the floor, and this causes adhesion failure in the intersection where the vertical and horizontal bar arrangements are complicated. Slip is surely prevented.

    “Plastic hinge” refers to a portion that exhibits plastic deformation performance when it is subjected to repeated positive and negative alternating deformations in a continuous reinforced concrete member, and can generally occur on both continuous and discontinuous surfaces. However, when a high-strength concrete member is connected to ordinary concrete as in Patent Document 2, it is normal that a plastic hinge is formed in the portion of ordinary concrete near the connection surface. This means is a technique for controlling the position of the place where the plastic hinge is formed by inserting a bending reinforcing bar at a necessary place in a structure having the same concrete strength and thickness (especially a continuous concrete structure without joints).

Further, this means has a part of the constituent requirement that “the end face 24 of the plastic region is seamlessly continuous with the reinforcing region 16 and is formed by on-site strike”.

According to this, since the bending reinforcement reinforcement for preventing slip is adopted in the factory-made wall floor type structure, it is not necessary to transport a high-strength concrete member near the intersection, and a plastic hinge is formed in a place where there is no seam. Since it did in this way, it can endure larger plastic deformation compared with the case where a plastic hinge is formed in a discontinuous surface.

  The second means comprises the first means, and
Inserting at least the crossing portion 12 a bending reinforcing bar 18 extending in the same direction as the through bar 10 of the wall plate 4, and
By extending the bending reinforcement 18 to the portion 14 adjacent to the intersection 12 of the wall plate,
The crossing portion 12 and the adjacent portion 14 are made rigid as a reinforcing region 16 that resists bending deformation and slippage due to adhesion failure of the bar arrangement,
The wall slab portion connected to the reinforcing region 16 is defined as a plastic region 22,
And a plastic hinge h at the end 23 of the plastic region in contact with the reinforcing region _p The formation locations are rearranged.

In this means, the structure applied to the floor slab by the first means is formed so as to be applied to the wall slab .

The third means includes the first means or the second means , and the amount of reinforcement of the bending reinforcement 18 in the above-described reinforcement region 16 is changed according to the amount and strength of the reinforcing reinforcement. The amount of rebar does not cause slippage due to adhesion failure of the penetration bar due to the axial force at the time of yielding of the penetration bar.

  That is, as the amount and strength of the reinforcing bar increases, the total amount of force acting on the surface of the reinforcing bar also increases. Therefore, in order to bear the bending reinforcing bar instead of the reinforcing bar through the force, the bending reinforcing bar It is necessary to increase the length. However, since the length of the bending reinforcing bar is limited, a plurality of bending reinforcing bars may be inserted into the reinforcing region, and the sum of the lengths may be a required length. Moreover, what is necessary is just to let the force which acts on these each reinforcing bar be the maximum force in the range which can be considered, ie, the force at the time of yielding of a reinforcing bar.

The fourth means has the first means,
The length of the bending reinforcing bar 18 in one of the floor slab 6 and the wall slab 4 is in a range of 2 to 3 times the thickness of the other slab.

  The length of the bending reinforcement is originally designed based on the amount of reinforcing bars as described above, but it is 2 to 4 times for normal buildings (about 10 stories or about 15 stories if seismic isolation). It only has to be about.

The fifth means includes any one of the first means to the fourth means, and the fixing portions 20 having a shape having a larger fixing force than the middle portion of the reinforcing bar are provided at both ends of the bending reinforcing bar 18. ing.

    This means proposes to clarify the position of the plastic hinge by providing fixing portions at both ends of the bending reinforcing bar. That is, by increasing the restraining force of the bending reinforcing bars at both ends of the reinforcing region, the plastic region without such restraining force is easily deformed, while the reinforcing region is difficult to deform. As a result, slippage due to adhesion failure of the bar arrangement in the reinforcing region can be prevented. The “fixing part” is a part having a large fixing force and having a function as an anchor, and may have any shape as long as the function is achieved. For example, both ends of one bending reinforcing bar may be hook-shaped bent portions as shown in FIG. 6 or may be enlarged diameter portions (not shown) having ribs or the like on the surface (not shown), and further bent as shown in FIG. The reinforcing bars may be looped and the corners may be used as fixing portions.

The sixth means includes any one of the first means to the fifth means, and the adhesion force of the penetration bar 10 at the intersecting portion 12 and the adhesion force of the penetration bar 10 at the adjacent portion 14. The concrete strength of the entire frame composed of the wall body and the floor slab is designed so that the total exceeds the necessary adhesion force of the bar reinforcement 10 in the reinforcing region 16.

In this means, when designing the concrete strength of the entire frame, it is proposed to consider the adhesive strength of the bar arrangement in the adjacent portion in addition to the adhesive strength of the bar arrangement in the intersection. In other words, when the adhesive strength of the penetration bar at the intersection is Tc, the adhesion strength of the penetration bar in the adjacent portion is Tn, and the required adhesion strength of the penetration bar is Ta, the following equation is obtained. The specific contents of this equation will be described later. When the compressive strength of concrete is σ _B , Tc∝ {1+ (σ ₀ / σ _B )) × σ _B ^2/3 , and Tn∝√ (σ _B ). On the other hand, it is a constant proportional to the JIS standard yield strength of the penetration bar, and from this, σ _B can be determined so as to satisfy Formula 1.
[Formula 1] Tc + Tn ≧ Ta
In addition, what is necessary is just to set the upper limit of the concrete strength of a housing so that appropriate deformation performance may be obtained. If the concrete strength is too high, the adhesion performance is too good and the energy absorption performance is high, but there is a demerit that the deformation performance is small. For example, the ultimate limit interlayer displacement angle may be designed to be 1.5 to 4%.

The invention according to the first means has the following effects.
O Since the bending reinforcement 18 is inserted in the wall-and-floor type structure with a uniform concrete strength, the formation location of the plastic hinge can be freely set according to the insertion location of the reinforcement.
○ Since the bending reinforcing bars 18 are inserted into the intersection and adjacent portions where the wall load is applied, the binding force of the reinforcing bars and the load can be combined to increase the adhesive strength of the reinforcing bars through the concrete.

Moreover , according to the invention which concerns on a 1st means, there exist the following effects.
○ Because the bending reinforcement bars are inserted at the intersection and the adjacent part in the wall-floored concrete structure cast in the field, it can be formed at a lower cost than when the intersection and the adjacent part are formed as separate precast members.
O Since the plastic region 22 is seamlessly connected to the reinforcing region 16, it is possible to effectively absorb seismic energy and to freely set the position of the plastic hinge as compared with the case where the plastic hinge is formed on the discontinuous surface.

Further, according to the invention relating to the second means, since the wall slab 4 and the floor slab 6 are reinforced by the bending reinforcing bars 18 respectively, the earthquake resistance is further enhanced .

According to the third aspect of the invention, since the length of the bending reinforcing bar 18 is set to such a length that does not cause slippage due to adhesion failure due to the axial force at the time of yielding of the reinforcing bar due to an earthquake, the range where the reinforcing bar does not yield It is possible to completely prevent slippage due to adhesion failure.

According to the fourth aspect of the invention, since the length of the bending reinforcing bar 18 in one member of the floor slab 6 and the wall slab 4 is set to be twice or more the thickness of one or the other member, In particular, slippage due to adhesion failure can be sufficiently prevented.

According to the fifth aspect of the invention, since the fixing portions 20 having a shape having a larger fixing force than the intermediate portion of the reinforcing bar are provided at both ends of the bending reinforcing bar 18, the starting position of the end portion of the plastic region 22 is determined. It becomes clear and advantageous in design.

According to the sixth means, the sum of the adhesive force of the bar reinforcing bar 10 at the crossing portion 12 and the adhesive force of the bar reinforcing bar 10 at the adjacent portion 14 is necessary for the bar reinforcing bar 10 in the reinforcing region 16. Since the concrete strength of the entire frame consisting of the wall and floor slabs is designed to exceed the adhesion force, slippage due to adhesion failure can be prevented and energy such as earthquakes can be absorbed sufficiently.

  1 to 8 show a concrete earthquake-resistant wall floor structure 2 according to a first embodiment of the present invention.

  As shown in FIG. 1, the wall-floor type structure 2 is integrally cast by a concrete wall slab 4, a floor slab 6, and a ceiling slab 8. In this specification, the term “wall slab” and “floor slab” refer to a flat plate-like structural material that forms a building frame. Although it may be called a wall board and a floor board, it is referred to in this way to distinguish it from a floor board as an interior material.

  First, heretofore known matters in the configuration of the present invention will be briefly described. The illustrated structure is formed in a multilayer box culvert shape, and can be used as an apartment house or a condominium. The wall slab 4, the floor slab 6, and the ceiling slab 8 are each a reinforced concrete plate, and a pair of upper and lower through bars 10 are passed through the floor slab and ceiling slab, and a pair of left and right through bars 10 are passed through the wall slab. . The wall slab 4, floor slab 6 and ceiling slab 8 intersect each other. At the intersection between the outer wall and the floor slab, and at the intersection between the ceiling slab and the inner wall, it intersects in a T shape (or a sideways T-shape), and intersects in a cross shape in other portions. At the intersection 12, the vertical penetration bar 10 and the horizontal penetration bar 10 cross each other.

  In the present invention, a bending reinforcing bar 18 is inserted from the intersecting part 12 to the adjacent part 14 continuous with the intersecting part, and the intersecting part 12 and the adjacent part 14 are reinforced by the binding force of the bending reinforcing bar. Region 16 is designated.

    The reinforcing region 16 is a cross or T shape as viewed from the side (front in the drawing), and extends in the depth direction along the ridgeline between the wall and the floor, and is bent and reinforced in the vertical and horizontal directions. It is rigidized by the restraining force of the muscles. Even if it says rigidification, it is only necessary to resist slippage between the concrete and the reinforcing bar against external pulling force and bending stress. However, it is also possible to apply prestress to the bending reinforcing bars and the through bars. By forming the reinforcing region 16 by the bending reinforcing bars intermittently in the front-rear direction of the wall slab 4 and the horizontal direction of the floor slab 6, the slippage of the reinforcing bars can be effectively prevented with a small amount of reinforcing bars. The reason why the bending reinforcement is inserted near the intersection is as follows. If a bending reinforcement is inserted in the middle part of the span of the floor slab between the intersecting parts, the weight of the middle part becomes excessive, which is not preferable. On the other hand, when bending reinforcements are inserted at the intersection and adjacent parts, the weight is applied to the walls, so that not only unnecessary deformation does not occur in the building, but the load is transmitted to the intersection of the lower layer, and this intersection Adhesion is improved because the slab reinforcement and the concrete are in close contact with each other.

  The crossing portion 12 is a portion shared by the floor slab and the wall slab in the housing. Among the reinforcing regions 16, the density of the reinforcing bars is the highest and plays the most important role in preventing slippage of the through bars 10.

  The adjacent portion 14 is a concrete portion that is adjacent to the intersection and is fixed to the vertical or horizontal portion of the bending reinforcement. As shown in FIG. 2 and FIG. 3, at the place where the wall slab and the floor slab intersect in a cross shape, there are four adjacent portions protruding from the intersection in the left-right direction and the up-down direction. In a place where the wall slab and the floor slab intersect in a T-shape as in 5, there are three adjacent portions. In general, the protruding length (width) L of the adjacent portion of the floor slab is approximately the same as the thickness of the wall slab, and the protruding length (vertical width) L of the adjacent portion of the wall slab is approximately the thickness of the floor slab. The same level is desirable. In the drawing, the floor slab and wall slab are drawn to the same thickness. However, when the wall slab thickness should be larger than the floor slab thickness, for example, in the lower floor of a building, the length of the adjacent portion is set for each. Set. More specifically, the description will be made in relation to the length of the bending reinforcement. However, the length of the adjacent portion 14 can be set larger than the standard length.

  The bending reinforcing bars 18 are arranged vertically and horizontally in the reinforcing region 16. In the floor slab, as shown in FIG. 2, the upper and lower reinforcing bars along the upper and lower reinforcing bars 10 are arranged in parallel with the reinforcing bars, respectively. All the bending reinforcement bars have the same length and extend between the outer ends of the left and right adjacent portions. A corresponding structure as shown in FIG. The bending reinforcing bar 18 has a pair of fixing portions 20 at both ends, and both the fixing portions are arranged at the ends of the reinforcing region, thereby firmly restraining the concrete in the reinforcing region. The fixing unit in the illustrated example has a hook shape, but the shape can be changed as appropriate. The length of the bending reinforcement is the sum of the lengths of the intersection and the adjacent portion. The length and number of bending reinforcement bars are designed so as not to cause slippage due to adhesive breakage of the penetration bar due to the axial force at the time of yielding of the penetration bar, depending on the amount and strength of the penetration bar. .

The floor slab portion and the wall slab portion adjacent to the reinforcing region 16 are portions that are more easily deformed than the reinforcing region, and are referred to as a plastic region 22 in this specification. The plastic zone is made of concrete with the same strength as the reinforced zone. The end face 24 of the plastic region 22 is continuous with the reinforcing area 16 seamlessly, plastic hinge h _p is generated in the end portion 23 of the plastic region when more than a predetermined swing is applied.

According to the above configuration, when the earthquake occurs, the crossing portion 12 and the adjacent portion 14 are constrained by the bending reinforcing bar 18, so that no deformation occurs in that range, and plastic deformation occurs in the plastic region 22 on the outer side. . In this case, where the plastic hinge h _p is formed is an end portion 23 of the plastic region 22, since the distance from the intersection, the slip due to the adhesion disruption of Reinforcement bending against the concrete is prevented.

Next, the procedure for designing the structure of the present invention will be described. In this invention, it designs so that the adhesive force in the cross | intersection part 12 and the adjacent part 14 may exceed the required adhesive force of a bar arrangement. Specifically, it is designed as the following Expression 2. Formula 2 is a specific example of Formula 1 (Tc + Tn ≧ Ta). In the following description, the adhesion of the bar slab reinforcement will be described.
[Equation _{2] π × d b × 0} τ u × D + π × d b × 1 τ u × 2 (r 0 × r 1 × D) ≧ (π / 4) × d b 2 × κ 1 × T σ _u (1 + γ)
Left first term of this formula _{2 (Tc = π × d b} × 0 τ u × D) represents the adhesion of through Haisuji portion in cross section. d _b is the diameter of the through Haisuji, ₀ tau _u is the adhesion strength in the cross section, D is the thickness of the wall plate. The meaning of this term is [adhesive force of the bar arrangement portion in the intersection] = [surface area of the bar arrangement portion] × [adhesion strength], which is a conventionally known matter. The adhesion strength in the intersection is determined by Equation 3. C ₁ is a constant that determines the adhesion strength at the intersection, and a suitable numerical value is 1.0 or 1.25. σ ₀ is the compressive axial stress degree (N / mm ² ) of the wall.
[Formula 3] ₀ τ _u = C ₁ × 0.7 {1+ (σ ₀ / σ _B )) × σ _B ^2/3 (N / mm ² )
Left side second term of Equation _{3 (Tn = π × d b} × 1 τ u × 2 (r 0 × r 1 × D)) represents the adhesion of through Haisuji part in the neighboring unit. ₁ τ _u is the adhesion strength in the adjacent portion. r ₀ is the ratio of the protrusion length of the adjacent portion to the wall thickness, and r ₁ is the length of the portion that effectively bears the adhesion stress (effective attachment length) of the protrusion length of the adjacent portion. When the interlaminar deformation angle R at the holding strength is 2% or less, r ₁ = 1.0 may be set. The adhesion strength in the adjacent portion is determined by Equation 4. C ₂ Suitable numerical constants defining the adhesion strength of the adjacent portion is 1.2.
[Formula 4] Tc = C ₂ × (0.4b _i +0.5) √ (σ _B ) (N / mm ² )
B _i is a constant given by b _i = [b / (Nb × d _b ) −1]. b is an arbitrary width of examination, and Nb is the number of bar arrangements in b.

The left side of Formula 3 is the necessary adhesion force of the bar arrangement. In the equation, κ ₁ is a coefficient for determining the strength for calculating the upper limit strength, _T σ _u is the JIS standard yield strength of the through bar, and γ is the double muscle ratio.

[Example 1]
Next, the relationship between the tensile strength ratio and the concrete strength was tested for various strength specimens according to the above calculation method. Here, r ₀ = 0.5, = 1.0. Reinforcing bars are D19, D22, and D25 (DN means that the diameter of the reinforcing bars is Nmm). The reinforcing bar yield strength is _T σ _u = 345 N / mm ² and κ ₁ = 1.25. FIG. 9 is a plot of the combination of the tensile reinforcement ratio pt and the concrete strength that does not satisfy Formula 2 under these conditions. The dotted line in the figure is a linear regression of all data. It is possible to obtain the minimum of concrete strength in response to the future p _t. It should be noted that the length of the beam is b, the formation (vertical width) is D, the effective formation (the distance from the upper end surface of the beam to the lower end) is d, and the number of the upper and lower ends in the length b is Assuming that the cross-sectional area of N _b pieces and each reinforcing bar is (π × d _b ² ) / 4, pt = {(π × d _b ² ) / 4} × N _b / (b × d). Using this, FIG. 9 is derived.

[Example 2]
An experiment was conducted to examine the seismic performance of each specimen in Table 1 using the concrete strength and the amount of reinforcing bars as parameters.

FIG. 10 shows data of specimen No. 10 having a medium concrete strength (σ _B = 29.7). This is an example in which the deformation and the load are well balanced. That is, the interlayer displacement angle is 7% or more, which shows sufficient deformation performance in terms of earthquake resistance. In addition, the energy absorption performance is equal to or better than that of a beam member in a general rigid frame. In addition, the judgment of the quality of energy absorption performance was performed by the equivalent viscous damping coefficient h _eq . FIG. 14 is a result of comparing the estimated value of the equivalent viscous damping constant (dashed line) of a general frame beam member with h _eq obtained from FIG. 10. According to the figure, the experimental value of the equivalent viscosity damping constant exceeds the estimated value, and it can be determined that the energy absorption characteristic is good.

Next, FIG. 11 shows data of specimen No. 3 having a slightly small concrete strength (σ _B = 27.4). Although the interlayer displacement angle is about 7%, the spindle-shaped area representing the load-deformation relationship is smaller than in FIG. 10, and the energy absorption performance is low. FIG. 15 is a diagram corresponding to FIG. 14 of the specimen No. 10, but the actual measurement value of the energy absorption performance is lower than the estimated value.

FIG. 12 shows data of specimen No. 8 having a large concrete strength (σ _B = 48.5). It can be seen that the load-deformation relationship is a sufficiently swollen spindle shape and rich in energy absorption characteristics. However, the deformation performance is poor and the fracture occurs when the interlayer displacement angle exceeds about 3%.

FIG. 15 is a plot of the combination of the reinforcing bar ratio p _t and the concrete compression strength as a result of summarizing the above considerations. The energy absorbing performance and Ductility both show good range S ₁ in hatching. S ₂ In contrast ranges is inferior in energy absorption performance slippage occurs due to adhesion breakdown, S ₃ is in a range inferior to the deformation performance Energy Characteristics is too large.

It is a perspective view which cuts out the front wall and shows the wall-floor type structure which concerns on embodiment of this invention. It is an expanded sectional view which shows the principal part of the structure of FIG. It is an expanded sectional view which shows the principal part of the structure of FIG. It is an expanded sectional view which shows the other principal part of the structure of FIG. It is an expanded sectional view which shows the other principal part of the structure of FIG. It is a figure which shows an example of the bending reinforcement used for the structure of FIG. It is a figure which shows the other example of the bending reinforcement used for the structure of FIG. FIG. 2 is an operation explanatory diagram of a main part of FIG. 1. It is a graph which shows the result of the load-deformation experiment of the test body of the structure of FIG. It is 1 of the result of having performed the load-deformation test of the structure of FIG. 1 changing conditions. It is 2 of the result of having performed the load-deformation test of the structure of FIG. 1 changing conditions. 3 is a result 3 of the load-deformation test of the structure of FIG. 1 performed under different conditions. It is the graph which analyzed the result of FIG. It is the graph which analyzed the result of FIG. It is the graph which put together the result of the test of FIGS. 1 is an end view of a concrete member corresponding to the intersection of a prior art floor and wall. FIG.

Explanation of symbols

2 ... Wall floor type structure 4 ... Wall slab 6 ... Floor slab 8 ... Ceiling slab 10 ... Through bar 12 ... Intersection 14 ... Adjacent part 16 ... Reinforcement region 18 ... Bending reinforcement 20 ... Fixing part 22 ... Plastic region 23 ... end 24 ... end surface h p _... plastic hinge

Claims (6)

In a concrete earthquake-resistant floor wall structure in which a plurality of concrete wall slabs and floor slabs intersect each other, and through the intersections, bar reinforcements are arranged in the wall slab and floor slab.
The wall slab ( 4 ) and floor slab ( 6 ) including the intersection ( 12 ) are formed with almost uniform concrete strength,
Is inserted into at least intersection through Haisuji (10) and extending in the same direction bending reinforcement (18) of the slab (6) (12),
The bending reinforcement (18) that extend into portions (14) adjacent intersection of the slab and (12),
These crossing portions ( 12 ) and adjacent portions ( 14 ) are rigidized as a reinforcing region ( 16 ) that resists bending deformation and slippage due to adhesive breakage of the bar arrangement,
The floor slab part connected to the reinforcement region ( 16 ) is the plastic region ( 22 ) ,
And repositioning the plastic hinge ( h _p ) formation at the end of the plastic region ( 23 ) in contact with the reinforcing region,
A concrete seismic wall-type floor structure, characterized in that the end face (24) of the plastic region is seamlessly continuous with the reinforcing region (16) and is formed by on-site striking . At least intersection through Haisuji (10) and extending in the same direction bending reinforcement (18) of the wall plate (4) is inserted into (12),
The bending reinforcement (18) that extend into portions (14) adjacent intersections of the walls plate (12),
These crossing portions ( 12 ) and adjacent portions ( 14 ) are rigidized as a reinforcing region ( 16 ) that resists bending deformation and slippage due to adhesive breakage of the bar arrangement,
The wall slab portion connected to the reinforcement region ( 16 ) is defined as a plastic region ( 22 ) ,
And it is characterized in that relocate the plastic hinge (h _p) the area where the end of the plastic region in contact with the reinforcing region (23), concrete shear wall bed structure according to claim 1, wherein. The amount of reinforcement of the bending reinforcement ( 18 ) in the reinforcement region ( 16 ) described above is determined by the axial force at the time of yielding of the reinforcing bar due to the earthquake according to the reinforcing bar quantity and strength of the reinforcing bar. The concrete seismic wall-type floor structure according to claim 1 or 2 , wherein the amount of rebar does not cause slippage due to adhesion failure. The length of the bending reinforcing bar ( 18 ) inside one of the floor slab ( 6 ) and wall slab ( 4 ) is in the range of 2 to 3 times the plate thickness of one or the other. A concrete earthquake-resistant wall floor structure according to claim 1. 5. A fixing portion ( 20 ) having a shape having a larger fixing force than that of an intermediate portion of the reinforcing bar is provided at both ends of the bending reinforcing bar ( 18 ) , according to any one of claims 1 to 4. Concrete earthquake resistant wall floor structure. Total adhesion through at intersections (12) Haisuji (10) and the adhesive force through Haisuji (10) at the adjacent portion (14), through Haisuji (10 in the reinforcing region (16) in characterized in that the concrete strength of the whole skeleton was designed consisting of walls and a floor plate to exceed the required adhesion), concrete shear wall bed structure according to any one of claims 1 to 5 .

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