JP6773509B2 - Building seismic design methods and programs for seismic design - Google Patents

Description

This disclosure relates to seismic design methods and programs for seismic design of buildings. In particular, the present invention relates to a method and a program for performing seismic design after evaluating the strength of the intersection between the vertical member and the horizontal member.

In concrete buildings, there are parts that are adjacent to each other but have different strengths required for concrete, such as beams and floor slabs and walls or columns and floor slabs.

In the case of beams and floor slabs in such an adjacent structure of concrete, the effective width is set for the floor slab extending from the top of the beam to the side in consideration of the influence of the floor slab on the beam, and the beam is set. A general design method is to calculate the bending moment by regarding the floor slab of the effective width portion as an integrated T-beam. Further, for example, Patent Document 1 proposes a method of calculating the shear force by regarding the beam as a T-shaped beam.

Japanese Unexamined Patent Publication No. 2006-97320

However, for the intersection of a vertical member such as a wall or a column and a horizontal member such as a floor slab or a beam, there is no design method considering the influence of both members like a beam and a floor slab. When concretes of different strengths intervene, it is common to calculate the member strength with the lower concrete strength as a measure to ensure safety.

For example, as shown in FIG. 9, the intersection 4 between the floor slab 1 and the walls 2 and 3 is formed so that the floor slab 1 penetrates between the wall 2 on the lower floor and the wall 3 on the upper floor. In this case, assuming that the concrete strength of the wall 2 on the lower floor is A, the concrete strength of the floor slab 1 is B, and the concrete strength of the wall 3 on the upper floor is C, the concrete strength required for the floor itself is usually required for the wall. Since it is lower than the concrete strength, B <A = C. Further, in general, the higher the concrete strength, the higher the Young's modulus. Therefore, as shown by the broken line in the figure, the floor slab 1 is distorted more than the walls 2 and 3. In the design of the earthquake-resistant wall including the walls 2 and 3 of the upper floor and the lower floor and the intersection 4, if both ends of the floor slab 1 are free ends and there is nothing to restrain the strain of the floor slab, the upper floor and the floor slab The intersection 4 is destroyed before the walls 2 and 3 on the lower floors.

Using the same high-strength concrete as walls and columns for floor slabs to prevent intersections from breaking first increases material costs and increases the burden of construction management to prevent shrinkage cracks.

Also, use the same high-strength concrete as the walls and columns at the intersections, and use low-strength concrete for the floor, and in order to prevent destruction at the intersections, concrete stoppers around the walls and columns It is necessary to install a frame and separate the concrete, resulting in poor workability.

In view of the above problems, the present invention provides a seismic design method capable of designing a building having an intersection between a horizontal member and a vertical member, which can suppress the material cost, reduce the burden of construction management, and have good workability. The purpose is to provide a program for its seismic design.

The seismic design method of the building (10) according to at least some embodiments of the present invention is vertical to a concrete horizontal member (11) extending in a predetermined horizontal direction so as to be orthogonal to the predetermined horizontal direction. It is a seismic design method for a building including a pair of vertical members (12) made of concrete, which extend in the direction, are connected to the upper and lower surfaces of the horizontal member, and have a higher compressive strength than the horizontal member. The step of setting the compressive strength (σ _B1 ) of the vertical member, the step of setting the compressive strength (σ _B ) of the horizontal member, and the intersection located between the vertical members in the horizontal member ( A step of replacing the function of the portion of the horizontal member adjacent to 13) to prevent the intersection from expanding in the predetermined horizontal direction by receiving a vertical compressive force generated by an earthquake with a virtual restraint spring (15). And the step of calculating the lateral pressure (σ _r ) acting on the intersection in the predetermined horizontal direction when the seismic force is received by using the spring constant (k) of the restraining spring, and the horizontal member. By correcting the compression strength (σ _B ) of the above in consideration of the restraining effect of the lateral pressure, the step of calculating the equivalent compression strength (σ _B ') of the intersection and the equivalent compression strength (σ _B ') are When the compression strength of the vertical member (σ _B1 ) or more, the compression strength of the intersection is set to the value of the compression strength (σ _B1 ) of the vertical member for design, and the equivalent compression strength (σ _B ′) is If the less than the compression strength of the vertical member (sigma _B1), to increase the compressive strength of the horizontal member (σ _B), the equivalent compressive strength (σ _B ') compressive strength of the vertical member (sigma _B1) It is characterized by including a step of setting and designing as described above. When the equivalent compressive strength (σ _B ') is smaller than the compressive strength (σ _B1 ) of the vertical member, the compression strength of the vertical member is set to the value of the equivalent compressive strength (σ _B ') for design. You may. Here, the "horizontal member" refers to a member extending in the horizontal direction such as a floor slab or a beam, and the "vertical member" refers to a member extending in the vertical direction such as a wall or a pillar. ..

According to this configuration, seismic design can be performed without underestimating the strength of the intersection, so the material cost can be suppressed and shrinkage cracks can be prevented compared to the case where the same high-strength concrete as the vertical member is used for the horizontal member. The burden of construction management to prevent it can be reduced. In addition, compared to the case where the same high-strength concrete as the vertical member is used for the intersection and low-strength concrete is used for the horizontal member other than the intersection, it is not necessary to install a stop formwork, so the workability is good. Is.

In the seismic design method for a building according to at least some embodiments of the present invention, in the above configuration, a plurality of sets of the vertical members are arranged in the predetermined horizontal direction, and the restraint springs are arranged in the predetermined horizontal direction. It is characterized in that the spring constant of the restraining spring is obtained by setting it as representing the elasticity of the portion of the horizontal member corresponding to the portion extending from the center line between the vertical members adjacent to each other to the intersection. .. In particular, when the vertical member forms a wall and the horizontal member forms a floor slab, the restraining spring is used in a predetermined range of a bending compression region due to seismic force at the intersection in a plan view. It can be set to represent the elasticity of the isosceles trapezoidal portion in which the center line is the base and the angle between the wall and the leg is 0 ° or more and 45 ° or less.

According to this configuration, the spring constant of the restraint spring can be easily obtained.

The seismic design method for a building according to at least some embodiments of the present invention has a correspondence relationship between the compressive strength (σ _B ) of the horizontal member and the equivalent compressive strength (σ _B ') in the above configuration. In the step of setting the compression strength (σ _B ) of the horizontal member, which further comprises a step of creating the table or graph shown, the equivalent compression strength (σ _B ') is the compression of the vertical member based on the table or graph. It is characterized in that the compressive strength (σ _B ) of the horizontal member is set so as to be _{equal to} or higher than the strength (σ _B1 ).

According to this configuration, the compressive strength required for the horizontal member can be easily grasped, and the re-design calculation can be suppressed.

In addition, the program for seismic design of the building (10) according to at least some embodiments of the present invention includes a concrete horizontal member (11) extending in a predetermined horizontal direction and the predetermined horizontal direction. For seismic design of a building provided with a pair of upper and lower vertical members (12) made of concrete, which are orthogonal to the horizontal member, are coupled to the upper and lower surfaces of the horizontal member in an intersecting direction, and have higher strength than the horizontal member. In the program, a means (ST1) for accepting an input of the compressive strength (σ _B1 ) of the vertical member, a means (ST3) for accepting an input of the compressive strength (σ _B ) of the horizontal member, and the horizontal member. The virtual restraint spring (15) has a function of suppressing the intersection from expanding in a predetermined horizontal direction by receiving an earthquake force by the portion of the horizontal member adjacent to the intersection located between the vertical members. A means for calculating the lateral pressure (σ _r ) acting in the predetermined horizontal direction on the intersection when a seismic force is applied by using the replacement means (ST4) and the spring constant (k) of the restraint spring. (ST5) and means (ST6) for calculating the equivalent compressive strength (σ _B ') of the intersection by correcting the compressive strength (σ _B ) of the horizontal member in consideration of the restraining effect due to the lateral pressure. the case equivalent compressive strength (σ _B ') is compressive strength (sigma _B1) or of the vertical member, means for setting the compressive strength of the intersection of the value of compressive strength (sigma _B1) of the vertical member (ST8 ) To make the computer work. Further, in the program, when the equivalent compressive strength (σ _B ′) is smaller than the compressive strength (σ _B1 ) of the vertical member, the equivalent compressive strength (σ _B ′) is the compressive strength (σ _B1 ) of the vertical member. Means for accepting the choice of re-entering the compressive strength (σ _B ) of the horizontal member or setting the compressive strength of the vertical member to the value of the equivalent compressive strength (σ _B ') in order to achieve the above. The computer may function as (ST9).

According to this configuration, seismic design can be performed without underestimating the strength of the intersection, so material costs can be suppressed and construction management can be performed compared to the case where the same high-strength concrete as the vertical member is used for the horizontal member. The burden can be reduced. In addition, compared to the case where the same high-strength concrete as the vertical member is used for the intersection and low-strength concrete is used for the horizontal member other than the intersection, it is not necessary to install a stop formwork, so the workability is good. Is.

Further, the building (10) having the seismic design structure according to at least some embodiments of the present invention is oriented so as to be orthogonal to the horizontal member (11) made of concrete extending in a predetermined horizontal direction. A building with a seismic design structure that extends in the vertical direction, is coupled to the upper and lower surfaces of the horizontal member, and has a pair of vertical members (12) made of concrete and has a higher compressive strength than the horizontal member. The intersection (13) located between the vertical members in the horizontal member is subject to the restraining effect of the portion of the horizontal member adjacent to the intersection in the predetermined horizontal direction. the compressive strength of the vertical member (sigma _B1), the greater than the compression strength of the horizontal member (sigma _B), compressive strength in consideration of the influence of in the restraining effect during an earthquake the horizontal member (sigma _B) The equivalent compression strength (σ _B ′) of the intersection calculated by correction is larger than the compression strength (σ _B1 ) of the vertical member.

According to this configuration, the building has a given seismic performance and the strength of the intersection is not underestimated, so it is not necessary to use the same high-strength concrete as the vertical member for the intersection. Therefore, the material cost can be suppressed, the burden of construction management for preventing shrinkage and cracking can be reduced, and the workability is good because it is not necessary to install a stop form.

According to the present invention, seismic design can be performed without underestimating the strength of the intersection, so that the material cost can be suppressed as compared with the case where the same high-strength concrete as the vertical member is used for the horizontal member, and the construction management can be performed. The burden can be reduced. In addition, compared to the case where the same high-strength concrete as the vertical member is used for the intersection and low-strength concrete is used for the horizontal member other than the intersection, it is not necessary to install a stop formwork, so the workability is good. Is.

Schematic vertical cross-sectional view of the building according to the embodiment Schematic partial cross-sectional plan view of the building according to the embodiment The figure which shows typically the structure equivalent to the wall and floor slab which concerns on embodiment. Longitudinal section showing the strength of the material of the wall and floor slab according to the embodiment. Flow chart of the design method according to the embodiment A model diagram in which the influence of the floor slab on the intersection is replaced with an equivalent restraint spring in the wall and floor slab according to the embodiment. Partial sectional plan view showing a part set as a restraint spring in the elastic part of the floor slab according to the embodiment. Graph showing the relationship between the concrete strength of the floor slab according to the embodiment and the concrete strength when the lateral pressure is taken into consideration. Vertical cross-sectional view for explaining the design method of the wall and floor slab according to the prior art.

Hereinafter, the design method of the building 10 according to the embodiment will be described with reference to the drawings. As shown in FIG. 1, the building 10 has a reinforced concrete floor slab 11 extending in the horizontal direction and a floor slab 11 extending in the vertical direction and bonded to the upper and lower surfaces of the floor slab 11, and has a higher compressive strength than the floor slab 11. It is provided with a reinforced concrete wall 12 in which the concrete having the above is used. The lower floor wall 12 and the upper floor wall 12 are arranged at positions that are vertically aligned with each other. It is preferable that the building 10 has a plurality of walls 12 orthogonal to the longitudinal direction of the building, such as a plate-shaped apartment house. The inertial force (seismic force) generated in the building 10 by the earthquake acts like a horizontal force when the building 10 is fixed to the ground, as shown by the arrows in FIG. The building 10 is considered to have mass concentrated on the floor level, and the horizontal force parallel to the wall 12 is designed to act on the floor level of each floor. Due to this seismic force, a compressive bundle concentrated in the lower right part of the building 10 in FIG. 1 is formed, so that a force is also generated in the vertical direction, and the intersection 13 between the floor slab 11 and the wall 12 (see FIG. 3) is affected. , A region that receives a compressive force in the vertical direction and a region that receives a tensile force are generated.

FIG. 2 is a cross-sectional view of an intermediate portion on a floor of the building 10, and both ends of the wall 12 are joined to columns 14. Thick arrows in the figure indicate seismic force. A tensile force acts in the vertical direction (Z direction) on the side of the wall 12 that receives the seismic force, and a compressive force acts in the vertical direction on the opposite side. In the region where the compressive force acts, the intersection 13 (see FIG. 3) between the floor slab 11 and the wall 12 is compressed in the vertical direction, so that the wall 12 and the wall 12 are as shown by the thin arrows in FIG. It tries to spread in the horizontal direction (X direction) that is orthogonal to each other. However, since the distance between the walls 12 adjacent to each other in the X direction does not change even during an earthquake, the deformation of the intersection 13 is suppressed by the portion of the floor slab 11 adjacent to the intersection 13.

It can be said that the action of such a force during an earthquake is equivalent to the structure shown in FIG. 3 in which the deformation in the X direction is constrained by the center line between the walls 12 adjacent to each other in the X direction. In this embodiment, the concrete strength of the intersection 13 is calculated in consideration of the restraining effect of the floor slab 11 on the intersection 13, and the seismic design is performed.

As shown in FIG. 4, the concrete compressive strength of the floor slab 11 is σ _B , the compressive strength of the wall 12 is σ _B1, and the design procedure will be described with reference to the flowchart of FIG.

First, basic data such as the concrete compressive strength σ _{B1 of} the wall 12 and the shapes of the floor and the wall 12 are input (ST (step) 1).

Next, the presence or absence of the floor slab 11 is confirmed (ST2). If there is no floor slab 11, the design method according to this embodiment does not apply. If there is a floor slab 11, the concrete compression strength σ _B of the floor slab 11 is input (ST3).

Next, the restraint state of the intersection 13 shown in FIG. 3 is replaced with the virtual restraint spring 15 shown in FIG. 6, and the spring constant k of the restraint spring 15 is calculated (ST4). In FIG. 6, the thick arrow indicates the vertical compressive force generated by the seismic force, and the broken line schematically shows the shape of the intersection 13 deformed by the compressive force. Assuming that the displacement of the intersection 13 in the Z direction is Δz and the displacement spreading to one side in the X direction is 1 / 2Δx, the magnitude of Δx is suppressed by the restraint spring 15. For example, the restraint spring 15 can be set to represent the elasticity of the isosceles trapezoidal region of the floor slab 11, which is shown in the thin dot pattern in FIG. In FIGS. A, B, and C of FIG. 7, the wall 12 is not joined to the pillar 14, the pillar 14 is joined to both ends of the wall 12, and the pillar 14 is joined to both ends of the wall 12, respectively. The beam 16 extends from the column 14 in the direction orthogonal to the wall 12, and the spring constant k of the restraint spring 15 is calculated by the same calculation method in any form. be able to. The walls 12 and pillars 14 shown in FIG. 7 have cross sections, but hatching for showing the cross sections is omitted.

One base of the trapezoid is a boundary portion with the intersection 13, and receives a compressive force in the X direction from the intersection 13. The other base of the trapezoid is the midline between the walls 12 adjacent to each other and is the support portion 17 that supports the elastic portion. In the wall 12 and the intersection 13, a shear failure determination region 18 shown by a dark dot pattern in FIG. 7 is set in the bending compression region, and the length in the horizontal direction (Y direction) along the wall 12 is l. It is _sc . The position of the base of the trapezoidal intersection 13 side corresponds to the portion adjacent to the shear failure determination region 18 in a plan view. The shear failure determination region 18 is 1/3 of the length of the wall 12 in the Y direction from the end of the wall 12 and the intersection 13 opposite to the side receiving the seismic force toward the side receiving the seismic force. The area is up to about 1/2. The angle θ between the X direction (the direction from the wall 12 toward the support portion 17 and the height direction of the trapezoid) and the trapezoidal legs is 0 ° or more and 45 ° or less, and the length l _B of the base on the support portion 17 side. Is greater than or equal to the length l _sc of the base on the intersection 13 side. Regarding the restraint spring 15 on the side where there is no other wall 12 in the wall 12 provided on the end side of the building 10, the beam 19 (see FIG. 2) provided at the slab end and the X direction. In order to restrain the deformation of the floor slab 11, bending reinforcing bars 20 (see FIG. 2) extending in the horizontal direction (Y direction) parallel to the wall 12 are installed, and these are represented by the restraining spring 15. The floor slab 11 The support portion 17 of the trapezoidal elastic portion may be used.

ｋ：ばね定数
ω：設計上の安全率（１．０以下）
ｔ_ｓ：床スラブ１１の厚さ
ｌ_Ｂ：支持部１７側の底辺の長さ
ｌ_ｓｃ：壁１２及び交差部１３の曲げ圧縮領域に於けるせん断破壊判定領域の長さ（交差部１３側の底辺の長さ）
ｈ_ｓ：壁１２から支持部１７までの距離（台形の高さ）
Ｅ_ｃ：床スラブ１１のヤング係数 The spring constant k of the restraint spring 15 is calculated based on the deflection when a compressive force acts on the trapezoidal plate in the X direction. First, the deflection of a minute section in the X direction (the height direction of the trapezoid) is obtained, and this is integrated in the X direction to obtain the total deflection. Here, the compressive force in the X direction is calculated assuming that it is evenly applied to the entire target area. Next, the compressive force is divided by the total deflection to calculate the spring constant k. The spring constant k based on the above calculation is expressed by the following equation. If the left and right specifications of the wall 12 (slab thickness t _s , span h _s , Young's modulus E _c, etc.) are different, the spring constants k for each are calculated and the average value is used.

k: Spring constant ω: Design safety factor (1.0 or less)
t _s : Thickness of the floor slab 11 l _B : Length of the base on the support portion 17 side l _sc : Length of the shear failure determination region in the bending compression region of the wall 12 and the intersection 13 (on the intersection 13 side) Bottom length)
h _s : Distance from wall 12 to support 17 (height of trapezoid)
E _c : Young's modulus of floor slab 11

Δｘ：Ｘ方向に拡がる変位
ν：コンクリートのポアソン比
ε_ｚ：圧縮ひずみ（交差部１３のＺ方向の変位（Δｚ）／床スラブ１１の厚さ（ｔ_ｓ））
ｔ_ｗ：壁１２の厚さ Next, as shown in FIG. 5, the lateral pressure σ _r acting on the intersection 13 from the restraint spring 15 is calculated (ST5). First, the displacement Δx that spreads in the X direction of the intersection 13 is obtained. The displacement Δx is expressed by the following equation.

[Delta] x: displacement extends in the X direction [nu: Poisson's ratio of the concrete epsilon _z: Compression strain (Z-direction displacement of the intersection 13 (Δz) / thickness of the floor slab 11 _(t s))
t _w : Thickness of wall 12

σ_ｒ：側圧
α_ｓ：床スラブ１１の状況による係数。壁１２がｘ方向の両側から拘束される場合（壁１２に対してｘ方向の両側に床スラブ１１等がある場合）α_ｓ＝２、片側からのみ拘束される場合（壁１２に対してｘ方向の片側にのみ床スラブ１１等がある場合）α_ｓ＝１。 Next, the lateral pressure σ _r is obtained from Δx and the spring constant k. The lateral pressure σ _r is expressed by the following equation.

σ _r : Lateral pressure α _s : Coefficient according to the situation of the floor slab 11. When the wall 12 is restrained from both sides in the x direction (when there are floor slabs 11 and the like on both sides in the x direction with respect to the wall 12) α _s = 2, when restrained only from one side (x with respect to the wall 12) If there is a floor slab 11 etc. on only one side of the direction) α _s = 1.

σ_Ｂ'：等価圧縮強度
σ_Ｂ：床スラブ１１のコンクリート圧縮強度（交差部１３の材料強度） Then, to calculate the equivalent compressive strength of the intersecting portion 13 σ _B '(ST6). The intersection 13 has a strength higher than the material strength (concrete compression strength σ _B of the floor slab 11) due to the restraining effect of the lateral pressure σ _r from the floor slab 11. Equivalent compressive strength sigma _{B 'is} the intensity of the material strength was corrected in consideration of the constraint effects. It is known that the compressive strength of restrained concrete is increased, and various calculation methods have been proposed. Equivalent compressive strength sigma _{B 'can} be calculated by any of them calculation methods. For example, it can be calculated by the following formula.

σ _B ': Equivalent compressive strength σ _B : Concrete compressive strength of floor slab 11 (material strength of intersection 13)

Next, compare the magnitude of the concrete compressive strength sigma _B1 equivalent compressive strength sigma _B 'and the wall 12 (ST7).

Equivalent compressive strength sigma _{B 'is} not less than the concrete compressive strength sigma _B1 walls 12, when the seismic force is applied, breakdown occurs in the wall 12 (base material) before the intersection 13. Therefore, the compression strength of the intersection 13 in the calculation of the seismic design is set to the value of the compression strength of the wall 12 (ST8). That is, design, when considering the shear wall 21 from the wall 12 and the intersecting portion 13. are formed, the compressive strength of the entire shear walls 21, concrete equivalent compressive strength sigma _{B 'and} the wall 12 of the intersection 13 among the compressive strength sigma _B1, designed regarded as concrete compressive strength sigma _B1 wall 12 is a compression strength of the smaller.

Equivalent compressive strength sigma _{B 'is,} if it is determined that the wall 12 of concrete compressive strength sigma _B1 smaller than when the seismic force is applied, the wall 12 broken at the intersection 13 before the (base material) occurs. It is determined whether or not to design with such an intersection destruction type (ST9). When designing with the intersection fracture type, the compression strength of the wall 12 in the seismic design is set to the value of the equivalent compression strength σ _B '(ST10). In other words, the compressive strength of the entire shear wall 21 consisting of wall 12 and the intersection 13. Of the concrete compressive strength sigma _B1 equivalent compressive strength sigma _{B 'and} the wall 12 of the intersection 13 is the compressive strength of the smaller designing regarded as equivalent compressive strength sigma _{B 'of} intersection 13. If the design is not for the intersection fracture type, increase the value of the concrete compression strength σ _B of the floor slab 11 and start over from ST3.

Incidentally, with respect to the floor slab 11 and the wall 12 of typified shape, Ya graph showing a relationship between the concrete compressive strength of the floor slab 11 sigma _B equivalent compressive strength sigma _{B ',} such as the graph shown in FIG. 8 Table prepared in advance, and is at the ST3, the equivalent compressive strength sigma _{B 'is} set a value that is estimated to be more concrete compressive strength sigma _B1 wall 12 concrete compressive strength sigma _B of the floor slab 11 May be good.

A wall plate (horizontal bar D6 @ 85 mm, vertical bar D6 @ 50 mm) having a length of 1200 mm and a height of 900 mm, in which the lower end side is joined to the foundation beam and the upper end side is joined to the force beam, is used as an embodiment of the present invention. A test was conducted with a comparative example. In Comparative Example 1, the entire wall plate was cast with the same concrete. In Comparative Example 2, a low-strength layer having a height of 50 mm was provided on the legs of the wall plate, but the thickness was the same as that of the wall plate main body, and a portion corresponding to the floor slab was not provided. In Examples 1 to 4, a low-strength layer having a height of 50 mm is provided on the leg portion of the wall plate, and the low-strength layer is a slab having a length of 300 mm in a direction orthogonal to the wall plate, and is provided on both sides of the wall plate. It corresponds to the state where there is a floor slab. The slabs of Examples 1 to 4 are provided with slab bars (D6 @ 100 mm) for fixing the slab to the foundation beam, and the slabs of Examples 2 to 4 are U extending in a direction orthogonal to the wall plate. A character restraint muscle was provided. The U-shaped restraint bar of Example 2 was not fixed to the foundation beam, and both ends of the U-shaped restraint bar of Examples 3 and 4 were bent downward and fixed to the foundation beam. Table 1 shows the properties of the test piece.

Based on equations 1 4, to calculate the equivalent compressive strength sigma _{B 'of} Example 1-4. In calculating the equivalent compressive strength σ _B ', the design safety factor ω is 1.0, l _sc is 400 mm, which is 1/3 of the length of the wall plate, and the height of the trapezoidal part of the slab represented by the restraint spring. The angle θ between the direction and the leg (see FIG. 7) was 45 °, the Poisson's ratio ν was 0.4 (considering the plastic region), and the compressive strain ε _z was 2000 micron. In all tests of Examples 1-4, an equivalent compression strength sigma _{B 'was} greater than the compressive strength sigma _B1 wallboard body. In addition, the strength based on the material strength of the wall body and the strength based on the material strength of the low-strength layer were calculated.

A horizontal force parallel to the wall plate corresponding to the seismic force was applied to the test piece. The horizontal force was a positive / negative repeated force of increasing displacement. Table 2 shows the experimental results and calculation results.

Is In Examples 1-4, _'the equivalent compressive strength sigma _B, for greater than the compressive strength sigma _B1 wallboard body, according to the present invention, the entire wallboard combining the wallboard body and low-strength layer Can be regarded as the compressive strength σ _B1 of the wall body (ST8 in FIG. 5). Comparing the maximum load of the experimental values and the strength of the wall plate body with respect to Examples 1 to 4, the maximum load of the experimental values was larger, indicating the safety of the seismic design method according to the embodiment.

Further, in Comparative Examples 1 and 2, since the fracture was performed at a value smaller than the bending strength, the fracture type was judged to be shear fracture, but in Examples 1 to 4, the fracture type was determined to be fractured at a value larger than the bending strength. It is judged to be bending fracture.

Although the description of the specific embodiment is completed above, the present invention can be widely modified without being limited to the above embodiment. Instead of the intersection of the wall and the floor slab, the present invention may be applied to the intersection of the column and the floor slab, the intersection of the wall and the beam, or the intersection of the column and the beam. The shape of the elastic portion of the floor slab represented by the restraint spring may be changed. Further, the present invention may be applied to a program for operating a computer as a means corresponding to each step of the above embodiment.

10: Building 11: Floor slab (horizontal member)
12: Wall (vertical member)
13: Intersection 14: Column 15: Restraint spring 16: Beam extending in the X direction 17: Support part 18: Shear failure determination region 19: Beam extending in the Y direction 20: Bending reinforcement 21: Shear wall

Claims (7)

A concrete horizontal member extending in a predetermined horizontal direction, extending in the vertical direction so as to be orthogonal to the predetermined horizontal direction, being coupled to the upper and lower surfaces of the horizontal member, and having a higher compression than the horizontal member. It is a method of seismic design of a building equipped with a pair of upper and lower vertical members made of concrete, which has strength.
The step of setting the compressive strength (σ _B1 ) of the vertical member and
The step of setting the compressive strength (σ _B ) of the horizontal member and
The portion of the horizontal member adjacent to the intersection located between the vertical members in the horizontal member suppresses the intersection from expanding in the predetermined horizontal direction due to the vertical compressive force generated by the earthquake. Steps to replace the function to be with a virtual restraint spring,
Using the spring constant of the restraint spring, a step of calculating the lateral pressure acting on the intersection in the predetermined horizontal direction when receiving an seismic force, and
A step of calculating the equivalent compressive strength (σ _B ') of the intersection by correcting the compressive strength (σ _B ) of the horizontal member in consideration of the restraint effect due to the lateral pressure.
Wherein when the equivalent compressive strength (σ _B ') is compressive strength (sigma _B1) or of the vertical member, designed to set the compressive strength of the intersection of the value of compressive strength (sigma _B1) of said vertical member, 'If is smaller than the compressive strength of the vertical member (sigma _B1), to increase the compressive strength of the horizontal member (σ _B), the equivalent compressive strength (sigma _B the equivalent compressive strength (σ _B)') is A seismic design method for a building, which comprises a step of setting and designing the vertical member so as to have a compressive strength (σ _B1 ) or more. A concrete horizontal member extending in a predetermined horizontal direction, extending in the vertical direction so as to be orthogonal to the predetermined horizontal direction, being coupled to the upper and lower surfaces of the horizontal member, and having a higher compression than the horizontal member. It is a method of seismic design of a building equipped with a pair of upper and lower vertical members made of concrete, which has strength.
The step of setting the compressive strength (σ _B1 ) of the vertical member and
The step of setting the compressive strength (σ _B ) of the horizontal member and
The portion of the horizontal member adjacent to the intersection located between the vertical members in the horizontal member suppresses the intersection from expanding in the predetermined horizontal direction due to the vertical compressive force generated by the earthquake. Steps to replace the function to be with a virtual restraint spring,
Using the spring constant of the restraint spring, a step of calculating the lateral pressure acting on the intersection in the predetermined horizontal direction when receiving an seismic force, and
A step of calculating the equivalent compressive strength (σ _B ') of the intersection by correcting the compressive strength (σ _B ) of the horizontal member in consideration of the restraint effect due to the lateral pressure.
Wherein when the equivalent compressive strength (σ _B ') is compressive strength (sigma _B1) or of the vertical member, designed to set the compressive strength of the intersection of the value of compressive strength (sigma _B1) of said vertical member, When the equivalent compressive strength (σ _B ') is smaller than the compressive strength (σ _B1 ) of the vertical member, the step of designing by setting the compressive strength of the vertical member to the value of the equivalent compressive strength (σ _B '). Seismic design method of a building characterized by being equipped with. A plurality of sets of the vertical members are arranged in the predetermined horizontal direction.
The restraint spring is set as representing the elasticity of the portion of the horizontal member corresponding to the portion from the center line between the vertical members adjacent to each other in the predetermined horizontal direction to the intersection, and the restraint spring is set. The seismic design method according to claim 1 or 2, wherein the spring constant is obtained. The vertical member forms a wall,
The horizontal member forms a floor slab,
In a plan view, the restraint spring has a predetermined range of a bending compression region due to seismic force at the intersection and the center line as the base, and the angle formed by the direction from the wall toward the center line and the leg is The seismic design method according to claim 3, wherein the seismic design method is set to represent the elasticity of an isosceles trapezoidal portion having a temperature of 0 ° or more and 45 ° or less. Further provided with a step of creating a table or graph showing the correspondence between the compressive strength (σ _B ) of the horizontal member and the equivalent compressive strength (σ _B ').
In the step of setting the compressive strength (σ _B ) of the horizontal member, the horizontal member is set so that the equivalent compressive strength (σ _B ') is equal to or higher than the compressive strength (σ _B1 ) of the vertical member based on the table or graph. The seismic design method according to any one of claims 1 to 4, wherein the compressive strength (σ _B ) of the member is set. A concrete horizontal member extending in a predetermined horizontal direction and a concrete structure orthogonal to the predetermined horizontal direction, coupled to the upper and lower surfaces of the horizontal member in an intersecting direction, and having a higher strength than the horizontal member. It is a program for seismic design of a building equipped with a set of upper and lower vertical members.
A means for receiving an input of the compression strength (σ _B1 ) of the vertical member,
A means for receiving an input of the compression strength (σ _B ) of the horizontal member,
A virtual constraint on the function of the horizontal member portion adjacent to the intersection located between the vertical members in the horizontal member to prevent the intersection from expanding in a predetermined horizontal direction due to seismic force. Means to replace with springs
A means for calculating the lateral pressure acting on the intersection in the predetermined horizontal direction when a seismic force is applied by using the spring constant of the restraint spring.
A means for calculating the equivalent compressive strength (σ _B ') of the intersection by correcting the compressive strength (σ _B ) of the horizontal member in consideration of the restraining effect due to the lateral pressure.
Wherein when the equivalent compressive strength (σ _B ') is compressive strength (sigma _B1) or of the vertical member, the computer as a means for setting the compressive strength of the intersection of the value of compressive strength (sigma _B1) of the vertical member A program to make it work. When the equivalent compressive strength (σ _B ') is smaller than the compressive strength (σ _B1 ) of the vertical member, the equivalent compressive strength (σ _B ') is set to be equal to or higher than the compressive strength (σ _B1 ) of the vertical member. Make the computer function as a means of accepting the choice of re-entering the compressive strength (σ _B ) of the horizontal member or setting the compressive strength of the vertical member to the value of the equivalent compressive strength (σ _B '). The program according to claim 6, further comprising:

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