JP6409014B2 - Method for estimating rigidity of building and method for estimating natural frequency of building - Google Patents

Description

  The present invention relates to a technique for estimating a building stiffness and a method for estimating a natural frequency of a building.

  2. Description of the Related Art Conventionally, a method of providing a dynamic vibration absorber in a building is known as a method of reducing building vibration (vibration) caused by vibration caused by an earthquake or vibration caused by vehicle traffic. For example, as described in Patent Document 1.

  In the technique described in Patent Document 1, the horizontal primary natural frequency of the dynamic vibration absorber is set to be substantially equal to the horizontal primary natural frequency of the building. Thereby, the vibration of the building in the horizontal direction can be suppressed. Thus, in order to set the horizontal primary natural frequency of the dynamic vibration absorber, it is necessary to grasp the horizontal primary natural frequency of the building.

  The horizontal primary natural frequency of a building can be grasped by actually performing various measurements after the building is completed. However, from the viewpoint of simplification and efficiency improvement of the building construction process, it is desirable to estimate the horizontal primary natural frequency before the building is completed (design stage, etc.).

  Here, in a relatively high-rise building (for example, a high-rise building), the rigidity of the entire building is almost determined by the rigidity of the housing (structural member), so that the rigidity of the housing can be regarded as the rigidity of the entire building. Since the rigidity of the housing can be estimated relatively easily, the horizontal primary natural frequency of the building is estimated (calculated) using the estimated rigidity of the housing (that is, the rigidity of the entire building). Can do.

  However, in a relatively low-rise building (for example, a general house), a member other than the frame (for example, a non-structural member such as an outer wall or a boundary wall) greatly affects the rigidity of the entire building. It is difficult to accurately estimate the overall rigidity.

JP-A-5-287934

  The present invention has been made in view of the above situation, and the problem to be solved is a method for estimating the rigidity of a building capable of accurately estimating the rigidity of the building, and the natural frequency of the building. It is to provide an estimation method.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

That is, according to the first aspect, the first step of calculating the horizontal rigidity of the building frame with respect to the predetermined direction in the horizontal direction, and the component in the predetermined direction among the horizontal lengths of the non-structural members of the building. The second step of calculating a correction value by multiplying the predetermined coefficient by the correction coefficient, and correcting the horizontal rigidity of the building frame calculated in the first step by the correction value, thereby correcting the entire building in the predetermined direction. And a third step of calculating the horizontal rigidity.

  In the second aspect, in the second step, as the non-structural member, an outer wall and a field wall directly connected to the housing of the building are used.

In Claim 3, the horizontal primary natural frequency of the whole building is calculated using the horizontal rigidity of the whole building calculated by the method for estimating the rigidity of the building according to Claim 1 or Claim 2. It is.

  As effects of the present invention, the following effects can be obtained.

  In Claim 1, the rigidity of a building can be estimated accurately.

  In Claim 2, the rigidity of a building can be estimated more accurately.

In Claim 3, the horizontal primary natural frequency of a building can be estimated accurately.

The figure which showed the estimation method of the natural frequency of the building which concerns on one Embodiment. The side cross-sectional schematic diagram of the house which is an example of a building. Similarly the plane cross-sectional schematic diagram of a house. The plane cross-sectional schematic diagram which showed the example of the other house. (A) The figure which shows an example of the natural frequency estimated by the general estimation method. (B) The figure which shows an example of the natural frequency estimated by the estimation method which concerns on this embodiment. The block diagram which showed schematic structure of the natural frequency estimation system.

  Hereinafter, the X direction and the Y direction will be defined and described based on the arrows in the figure. The X direction and the Y direction are two directions orthogonal to each other in plan view (horizontal direction) (see FIGS. 3 and 4).

  Hereinafter, a method for estimating the natural frequency of a building according to an embodiment of the present invention will be described with reference to FIG. The method for estimating the natural frequency of the building according to the present embodiment takes into account the rigidity of the non-structural member as well as the frame (structural member), and then the horizontal primary characteristic of the entire building (structural member and non-structural member). This is for estimating the frequency. The method for estimating the natural frequency of the building also includes a method for estimating the rigidity of the building (for estimating the horizontal rigidity of the entire building).

  First, in step S101, the horizontal stiffness (rigidity Kc) in the X direction and the Y direction of the building frame is calculated based on the building structure calculation. When the building has a plurality of floors (layers), the rigidity Kc of each layer is calculated. The rigidity Kc can be calculated by dividing the shear force acting on each layer of the building calculated by the structural calculation by the horizontal displacement. In addition, as a method of structure calculation, it is possible to use various generally used methods.

  Next, in step S102, a correction value for correcting the stiffness Kc is calculated. The correction value is for calculating the horizontal rigidity of the entire building in consideration of the rigidity of the non-structural members of the building. The correction value is also calculated for each of the X direction and the Y direction, similarly to the stiffness Kc. When the building has a plurality of floors (layers), correction values (that is, Lgk and α described later) for each layer are calculated. The correction value is represented by Lgk × α. Lgk is the length of the outer wall and the boundary wall of the building. Α is a predetermined coefficient. Details of Lgk and α will be described later.

Next, in step S103, the horizontal stiffness (rigidity K) in the X direction and Y direction of the entire building is estimated (calculated) by correcting the stiffness Kc using the correction value (Lgk × α) calculated in step S102. ) Specifically, the horizontal rigidity (rigidity K) of the entire building is calculated by adding a correction value (Lgk × α) to the horizontal rigidity (rigidity Kc) of the building frame. That is, the stiffness K is calculated by the following formula 1.
K = Kc + Lgk × α (1)

  At this time, the X direction correction value is added to the X direction rigidity Kc, and the Y direction correction value is added to the Y direction rigidity Kc, whereby the X direction and Y direction rigidity K are obtained. When the building has a plurality of floors (layers), the rigidity K of each layer is calculated.

  Next, in step S104, the building weight at the time of the earthquake (building weight M) is calculated. The building weight M is used for building structure calculation. The building weight M is appropriately calculated in consideration of the weight of the building itself and the weight of the furniture arranged in the building. When a building has a plurality of floors (layers), the building weight M of each layer is calculated.

Next, in step S105, the horizontal primary natural frequency f in the X direction and the Y direction of the building is estimated (calculated) using the rigidity K and the building weight M obtained in steps S103 and S104 described above. . It is known that the horizontal primary natural frequency f is expressed by the following formula 2.
f = (1 / 2π) × √ (K / M) Equation 2

  That is, in step S105, the horizontal primary natural frequency f of the building is calculated by substituting the values of the stiffness K and the building weight M into the above formula 2. At this time, the horizontal primary natural frequency f in the X direction is obtained by using the rigidity K and the building weight M in the X direction, and the horizontal primary natural frequency in the Y direction is obtained by using the rigidity K and the building weight M in the Y direction. Each f is obtained.

  When the building has a plurality of floors (layers), the matrix [K] whose component is the rigidity K of each layer and the matrix [M] whose component is the building weight M of each layer are applied to the above equation 2, respectively. By doing so, the horizontal primary natural frequency f is obtained.

  As described above, the horizontal primary natural frequency f of the entire building can be estimated in consideration of the rigidity of not only the structural member but also the non-structural member by the method for estimating the natural frequency of the building of the present embodiment. The horizontal primary natural frequency f can be estimated before the building is completed if various pieces of information necessary for the structural calculation of the building are available. Etc. can be achieved.

  Next, the length (Lgk) of the outer wall and the boundary wall of the building used in step S102 described above will be described in detail.

  The outer wall and the boundary wall of the building are members (non-structural members) other than the structural members. Here, in this embodiment, the member used as the framework of a building is assumed as a housing (structural member). Further, as the non-structural member, a member (a member other than the structural member) that generally has little influence on the rigidity of the building is assumed.

  As an example, a specific example of a housing (also referred to as a structural member or primary member) and a non-structural member (also referred to as a secondary member) will be described using the building (house 1) illustrated in FIG. FIG. 2 shows a schematic side sectional view of a two-story wooden house 1. In the case of the house 1, the foundation 11, pillars (not shown), beams 12, and the like serve as a housing (structural member). Further, the outer wall 21, the boundary wall 22, the partition 23, the ceiling 24, the floor 25, and the like are non-structural members.

  Here, among non-structural members, non-structural members that are directly connected to the casing (structural member) in particular are considered to have a great influence on the horizontal rigidity of the entire building as compared to other non-structural members. Therefore, in the present embodiment, among the above-described non-structural members, only those directly connected to the housing are extracted, and the length (Lgk) of the extracted non-structural members is calculated. In the present embodiment, among the non-structural members, those supported (connected) by the structural members from above and below are regarded as being directly connected to the housing (structural member).

  Specifically, as shown in FIG. 2, the outer wall 21 on the first floor is connected to the foundation 11 and the beam 12 at the top and bottom, respectively. The outer wall 21 on the second floor is connected to the beam 12 at the top and bottom. The upper and lower sides of the boundary wall 22 are connected to the foundation 11 and the beam 12, respectively. Therefore, in the present embodiment, the outer wall 21 and the boundary wall 22 are extracted from the non-structural members, and the lengths of the outer wall 21 and the boundary wall 22 are calculated as Lgk.

  On the other hand, for example, since the partition 23 is connected to the ceiling 24 and the floor 25 on the first floor, the partition 23 is not considered to have a great influence on the horizontal rigidity of the entire building (house 1). . Therefore, in this embodiment, the length of the partition 23 is not taken into account when calculating Lgk.

  Lgk is calculated based on the non-structural members (outer wall 21 and boundary wall 22) extracted in this way. Hereinafter, a method of calculating Lgk based on the outer wall 21 and the boundary wall 22 (the outer wall and the boundary wall of the building) will be described with reference to FIG.

  In FIG. 3, the plane cross-sectional schematic diagram of the house 1 is shown. In FIG. 3, for simplicity of explanation, the boundary wall 22 of the house 1 is omitted, and only the outer wall 21 of the house 1 is shown. Lgk is calculated for each of the X direction and the Y direction, similarly to the rigidity Kc and the like.

  Specifically, among the outer walls 21 of the house 1, those provided along the X direction (in parallel with the X direction) (the outer wall 21X in FIG. 3) are considered to have a large effect on the rigidity in the X direction. It is done. Therefore, one of the outer walls 21 provided along the X direction (outer wall 21X) is extracted, and the horizontal length of the outer wall 21X (four outer walls 21X in the example of FIG. 3) (in plan view, The total value of the length along the X direction) is defined as Lgk in the X direction. In this way, Lgk in the X direction is calculated based on the component in the X direction out of the length of the outer wall 21.

  Similarly, the outer wall 21 of the house 1 that is provided along the Y direction (the outer wall 21Y in FIG. 3) is considered to have a large influence on the rigidity in the Y direction. Therefore, the outer wall 21 provided along the Y direction (outer wall 21Y) is extracted, and the horizontal length of the outer wall 21Y (five outer walls 21Y in the example of FIG. 3) (in plan view, The total value of the length along the Y direction) is defined as Lgk in the Y direction. In this way, Lgk in the Y direction is calculated based on the component in the Y direction out of the length of the outer wall 21.

  Although omitted in FIG. 3, when the extracted non-structural member includes the boundary wall 22, Lgk including the length of the boundary wall 22 in addition to the outer wall 21 is calculated.

  Moreover, as shown in FIG. 4, when the house 1 has the outer wall 21 (outer wall 21XY) inclined with respect to the X direction and the Y direction in a plan view, the length X of the outer wall 21XY is X. Lgk is calculated using the direction component (width WX) and the Y direction component (width WY) as the lengths along the X direction and the Y direction, respectively. That is, the total value of the horizontal length of the outer wall 21X and the width WX of the outer wall 21XY in the X direction is defined as Lgk in the X direction. Similarly, the total value of the horizontal length of the outer wall 21Y and the width WY of the outer wall 21XY in the Y direction is defined as Lgk in the Y direction. When the horizontal length of the outer wall 21XY is L and the angle formed by the outer wall 21XY with respect to the X direction is θ, the width WX in the X direction of the outer wall 21XY is L × cos θ, and the width WY in the Y direction of the outer wall 21XY is L × sin θ can be calculated respectively.

  Next, the predetermined coefficient (α) used in step S102 described above will be described in detail.

  Α used in step S102 is a coefficient for obtaining an appropriate stiffness K when calculating the above equation 1, that is, when calculating the stiffness K by correcting the stiffness Kc using Lgk. It is. An appropriate value of α is appropriately determined by experiments and statistics.

  As shown in the above equation 1, since the rigidity Kc and Lgk × α are added, the rigidity Kc and Lgk × α have the same dimension. Here, Lgk is a length and has a dimension different from the rigidity Kc. From this, it can be seen that α has an appropriate dimension such that Lgk × α (value obtained by multiplying by Lgk) has the same dimension as the stiffness Kc.

  Next, the method for estimating the natural frequency of the building according to the present embodiment (estimation method considering non-structural members) and the general estimation method (estimation method considering only the frame (structural members)) are compared. Thus, the superiority of this embodiment will be described.

  FIG. 5A shows an example of horizontal primary natural frequencies of a plurality of buildings estimated (calculated) by a general estimation method. More specifically, FIG. 5A shows the horizontal primary natural frequency of the building estimated by a general estimation method, and the horizontal primary natural frequency obtained by actually measuring the building. And shows the relationship. In the figure, the estimated horizontal primary natural frequency is referred to as “estimated natural frequency”, and the horizontal primary natural frequency obtained by actually measuring the building is referred to as “measured natural frequency”. Moreover, the broken line in a figure has shown the approximate straight line of the horizontal primary natural frequency (each point in a figure) about a some building.

  Here, the general estimation method is the horizontal primary natural frequency f using the horizontal rigidity (rigidity Kc) of the building frame in place of the horizontal rigidity (rigidity K) of the entire building in the above-described formula 2. Is a method of calculating That is, in this case, the rigidity of the outer wall and the field wall (non-structural member) is not considered.

  As shown in FIG. 5A, it can be seen that the general estimation method has large variations and low correlation. That is, it is understood that it is difficult to accurately estimate the horizontal primary natural frequency f without considering the rigidity of the outer wall and the field wall. In relatively low-rise buildings (general houses, etc.) that are greatly affected by the rigidity of the outer wall and the boundary wall, the correlation is considered to be particularly low.

  On the other hand, FIG. 5B shows an example of the horizontal primary natural frequencies of a plurality of buildings estimated (calculated) by the estimation method according to the present embodiment.

  As shown in FIG. 5B, it can be seen that in the estimation method according to the present embodiment, the points are arranged along the approximate straight line, and the correlation is high. That is, the horizontal primary natural frequency f can be accurately estimated by considering the rigidity of the outer wall and the field wall as in this embodiment. The estimation method according to the present embodiment is considered to be particularly useful in a relatively low-rise building (such as a general house) that is greatly affected by the rigidity of the outer wall and the boundary wall.

  Next, referring to FIG. 6, an example of a system for estimating (calculating) the horizontal primary natural frequency of a building using the method for estimating the natural frequency of the building according to the present embodiment (natural frequency estimation system). 100) will be described.

  The natural frequency estimation system 100 mainly includes a storage unit 101, a calculation unit 102, a display unit 103, and an input unit 104.

  The storage unit 101 stores various programs and data. The storage unit 101 includes an HDD, a RAM, a ROM, and the like.

  The calculation unit 102 performs various calculations according to the program stored in the storage unit 101. The calculation unit 102 is configured by a CPU.

  The display unit 103 displays various information. The display unit 103 is configured by a liquid crystal display or the like.

  The input unit 104 is for inputting various types of information. The input unit 104 includes a keyboard, a mouse, and the like.

  Thus, as the natural frequency estimation system 100, a general personal computer or the like can be used.

  In the natural frequency estimation system 100, various types of information related to the building to be estimated are input by the input unit 104. The computing unit 102 estimates (calculates) the horizontal primary natural frequency of the building from input information or information stored in advance in the storage unit 101 in accordance with a program stored in the storage unit 101 (see FIG. 1). ). Information on the estimation (the calculated horizontal primary natural frequency, its calculation process, etc.) is displayed on the display unit 103 and can be confirmed by the operator.

As described above, the method for estimating the rigidity of a building according to the present embodiment is as follows.
A first step (step S101) for calculating the horizontal rigidity (rigidity Kc) of the building frame with respect to a predetermined direction in the horizontal direction;
A second step (step S102) of calculating a correction value (Lgk × α) based on the length in the horizontal direction of the non-structural member of the building;
A third step of calculating the horizontal rigidity (rigidity K) of the entire building with respect to the predetermined direction by correcting the horizontal rigidity (rigidity Kc) of the building frame calculated in the first step based on the correction value ( Step S103)
It comprises.
By comprising in this way, the rigidity of a building can be estimated accurately.
That is, by estimating the rigidity of the building in consideration of non-structural members, it is possible to estimate the rigidity with higher accuracy.

In addition, the method for estimating the rigidity of a building according to this embodiment is as follows.
In the second step (step S102),
As the non-structural member, an outer wall and a field wall directly connected to the building frame are used.
By comprising in this way, the rigidity of a building can be estimated more accurately by considering the outer wall and the field wall considered to have a great influence on the horizontal rigidity of the building among non-structural members.

In addition, the method for estimating the rigidity of a building according to this embodiment is as follows.
In the second step (step S102),
The correction value (Lgk × α) is calculated based on the component in the predetermined direction out of the length of the non-structural member.
By comprising in this way, the rigidity of a building can be estimated more accurately.
That is, it is considered that the component in the direction of the length of the non-structural member greatly affects the horizontal rigidity of the entire building in a certain direction (predetermined direction). Therefore, by calculating the correction value based on the component, the rigidity of the building can be estimated with higher accuracy.

In addition, the method for estimating the natural frequency of the building according to this embodiment is as follows.
The horizontal primary natural frequency f of the entire building is calculated using the horizontal rigidity (rigidity K) of the entire building calculated by the above-described method for estimating the rigidity of the building.
By comprising in this way, the horizontal primary natural frequency of a building can be estimated accurately.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said structure, A various change is possible within the range of the invention described in the claim.

  For example, in the present embodiment, an example is shown in which the horizontal rigidity (rigidity K) of the entire building is estimated (calculated), and the horizontal primary natural frequency f of the building is estimated (calculated) using the rigidity K. However, the estimated stiffness K can be used for various other purposes.

  Further, in the present embodiment, the correction value (Lgk × α) is calculated by paying attention to non-structural members (outer wall and boundary wall) directly connected to the casing (structural member) among non-structural members. However, it is possible to extract an appropriate non-structural member according to the building and calculate the correction value.

  Moreover, in this embodiment, although the house 1 was illustrated as an example of a building, horizontal rigidity and a horizontal primary natural frequency can be estimated similarly about various other buildings.

DESCRIPTION OF SYMBOLS 1 Housing 11 Foundation 12 Beam 21 Outer wall 22 Border wall 23 Partition 24 Ceiling 25 Floor

Claims (3)

A first step of calculating the horizontal rigidity of the building frame with respect to a predetermined direction in the horizontal direction;
Of the length in the horizontal direction of the non-structural member of the building, a second step of calculating a correction value by multiplying a component in the predetermined direction by a predetermined coefficient ;
A third step of calculating the horizontal rigidity of the entire building with respect to the predetermined direction by correcting the horizontal rigidity of the building frame calculated in the first step by the correction value;
A method for estimating the rigidity of a building comprising: In the second step,
As the non-structural member, an outer wall and a field wall directly connected to the building frame are used.
The method for estimating the rigidity of a building according to claim 1. The horizontal primary natural frequency of the entire building is calculated using the horizontal rigidity of the entire building calculated by the method of estimating the rigidity of the building according to claim 1 or 2.
A method for estimating the natural frequency of a building.

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