JP2023161905A - Earthquake influence evaluation device and earthquake influence evaluation method - Google Patents

Abstract

To easily evaluate the influence of an earthquake on a steel member constituting a building of steel frame construction.SOLUTION: An earthquake influence evaluation device 10 comprises: an acquisition unit 11 that acquires a ductility range Ly of a beam member 2; a calculation unit 12 that calculates a yield ductility factor μy of the beam member 2 during an earthquake based on the ductility range Ly; and an evaluation unit 13 that evaluates the influence of the earthquake on the beam member 2 based on the yield ductility factor μy.SELECTED DRAWING: Figure 6

Description

The present invention relates to an earthquake impact evaluation device and an earthquake impact evaluation method.

Patent Document 1 discloses a device that grasps the state of a building based on how much the natural frequency of the building has changed before and after an earthquake.

JP2018-59718A

The device described in Patent Document 1 evaluates the soundness of the entire building, but in order to more accurately evaluate the impact of an earthquake on the building, it is necessary to It is necessary to understand the extent to which each object was deformed at the time. However, in order to measure the amount of deformation that occurs in each steel member during an earthquake, it is conceivable to install measurement sensors, etc. on each steel member, constantly measure with a recorder, and perform analysis after the earthquake. However, there is a risk that the measurement cost and the number of analysis steps will increase.

An object of the present invention is to enable easy evaluation of the effects of earthquakes on steel members constituting steel-framed buildings.

The present invention is an earthquake impact evaluation device that evaluates the impact of an earthquake on steel members constituting a steel frame building, and includes an acquisition unit that acquires the range of a plasticized region of a steel member; The present invention includes a calculation unit that calculates the plasticity rate of the steel member during an earthquake based on the range of , and an evaluation unit that evaluates the impact of the earthquake on the steel member based on the plasticity rate.

The present invention also provides an earthquake impact evaluation method for evaluating the impact of an earthquake on steel members constituting a steel frame building, which includes the steps of acquiring the range of a plasticized region of a steel member; The method includes the steps of calculating the plasticity rate of the steel member during an earthquake based on the range of the area, and evaluating the influence of the steel member due to the earthquake based on the plasticity rate.

According to the present invention, it is possible to easily evaluate the influence of an earthquake on steel members constituting a steel-framed building.

FIG. 2 is a diagram showing an example of a steel member (beam member) to be evaluated by the earthquake impact evaluation device according to the embodiment of the present invention. It is a graph which shows the relationship between the rotation angle and bending moment in the cross section of a beam member. FIG. 3 is a conceptual diagram for explaining a plasticized region that occurs in a beam member. It is a graph obtained by a constant amplitude repeated loading test. It is a graph showing the relationship between the number of repetitions and the plasticized region in a beam member obtained by a constant amplitude repeated loading test. It is a graph which shows the relationship between the plasticization area and yield plasticity rate in a beam member. It is a graph showing the relationship between fracture life and plasticity rate in a beam member. 1 is a block diagram showing the configuration of an earthquake impact evaluation system according to an embodiment of the present invention. 1 is a flowchart showing a processing procedure performed in an earthquake impact evaluation device according to an embodiment of the present invention. It is a graph showing the relationship between the yield plasticity rate and the plasticization area in a beam member obtained by a monotonic loading test. It is a graph which shows the relationship between the plasticization area and yield plasticity rate in a beam member obtained by a monotonous loading test.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An earthquake impact evaluation device and an earthquake impact evaluation method according to embodiments of the present invention will be described below with reference to the drawings.

The earthquake impact evaluation device 10 according to the embodiment of the present invention is a device for evaluating the impact of an earthquake on steel members such as beams and columns constituting a steel-framed building after an earthquake. Below, as shown in Figure 1, we will evaluate the effects of an earthquake on a beam member 2, which is welded to a column member 1 erected along the vertical direction and placed along the horizontal direction, after the earthquake. Let's explain the case. Note that the steel member to be evaluated by the earthquake impact evaluation device 10 is not limited to the column member 1, and may be a steel column member or a brace material.

The beam member 2 is an H-shaped steel material having a pair of flange portions 3 and 4 and a web portion 5 sandwiched between the pair of flange portions 3 and 4. This is a so-called built H-section steel formed by welding a steel plate to a steel plate that will become the web portion 5. Note that the beam member 2 may be a rolled H-shaped steel formed by rolling.

The beam member 2 has a pair of flange portions 3 and 4 attached to the column member 1 with a web portion 5 temporarily joined to a gusset plate 6 provided on the column member 1, which is a steel pipe column, via high-strength bolts (not shown). It is joined to the column member 1 by welding and joining to a pair of diaphragms 7 provided in the column member 1, respectively. Note that the connection of the web portion 5 to the column member 1 is not limited to bolt connection using high-strength bolts, and may be performed by directly welding the end surface of the web portion 5 to the column member 1.

When the beam member 2 joined to the column member 1 is damaged by an earthquake to the extent that permanent strain (residual strain) remains, a black crust (black crust) covering the flanges 3 and 4 occurs in the part where the permanent strain has occurred. Mill scale) and fireproof coating may peel off. Therefore, it is possible to visually determine to what extent the beam member 2 has become plasticized from the joint with the column member 1, which is the fixed end of the beam member 2.

In addition, in order to measure the plasticized region of the beam member 2, a measurement sensor such as a strain gauge or an optical fiber is placed in advance along the material axis direction (longitudinal direction) of the beam member 2, and the measurement sensor is placed after the earthquake. It is also possible to grasp the range in which strain (permanent strain) is detected as the range in which the beam member 2 has become plastic.

It is also possible to measure the hardness of the member by peeling off the fireproof covering covering the flange parts 3 and 4, and to determine the range where the hardness has increased due to the influence of permanent strain as the range where the beam member 2 has become plastic. be.

In this way, it is possible to understand the extent to which the beam member 2 has become plastic after an earthquake, but in order to more accurately evaluate the impact that the beam member 2 received during the earthquake, it is necessary to understand the extent to which the beam member 2 has become plastic during the earthquake. It is necessary to understand whether it has been deformed. However, in order to measure the amount of deformation that occurred in the beam members 2 during an earthquake, it is conceivable to install measurement sensors on each beam member 2, constantly measure with a recorder, and perform analysis after the earthquake. However, there is a risk that the cost required for measurement will increase and the number of man-hours required for analysis will also increase.

Therefore, in this embodiment, the extent of damage to the beam member 2 during the earthquake is estimated by using the size of the plasticized range of the beam member 2, which was determined after the earthquake using the various methods described above. are doing.

Here, the plasticization range Ly of the beam member 2 ascertained after the earthquake as described above is determined by the elastic gradient K in the relationship between the rotation angle θ and the bending moment M in the cross section of the beam member 2 shown in FIG. If the moment when the beam deviates from the line is the yield moment My, then this is the location where the deformation exceeds the yield moment My. For example, as shown in FIG. occurs over a predetermined range from the joint of the

FIG. 2 is a graph showing the results obtained from a so-called static monotonic loading test in which the strain and deformation degree of the beam member 2 is measured by stopping the application of a constant load or every constant deformation. The relationship between the rotation angle θ and the bending moment M in the cross section is shown. FIG. 3 is a moment diagram showing the bending moment M in the axial direction (longitudinal direction) of the beam member 2 when a load is applied to a predetermined loading point of the beam member 2.

As shown in FIG. 3, when a downward load P acts on a loading point that is a predetermined distance L from the joint between the beam member 2 and the column member 1, the bending moment M is applied from the loading point to the joint. It gradually increases in size toward the junction, and reaches its maximum (M=P·L) at the junction. Then, the portion where the bending moment M exceeds the yield moment My becomes plastic and becomes a plasticization range Ly. This also applies when an upward load (-P) is applied to the loading point.

The relationship between the magnitude of the load P and the magnitude of the plasticization range Ly shown in FIG. 3, that is, the relationship between the magnitude of the bending moment M and the magnitude of the plasticization range Ly, can be expressed as the following equation be done.

In the above equation 1, M is the bending moment at the end of the beam member 2, L is the distance from the joint between the beam member 2 and the column member 1 to the loading point, and My is the yield moment of the beam member 2. be. The loading point is determined from the bending moment diagram, etc., obtained by considering the long-term load and seismic load of the target beam.

As is clear from the above equation 1, the larger the bending moment M at the end of the beam member 2, the larger the plasticization range Ly, and the bending moment M at the end of the beam member 2 is smaller than the yield moment My. In other words, when the load P is relatively small, the plasticized range Ly does not occur in the beam member 2. Note that the plasticized range Ly is a range that includes a portion where the surfaces of the flange portions 3 and 4 of the beam member 2 are slightly plasticized, and means a range where the entire cross section of the beam member 2 is plasticized. It's not a thing.

In the following, the plasticization range Ly generated in the beam member 2 over a predetermined range from the joint is divided by the beam length H of the beam member 2 to make it dimensionless, and the parameter is expressed as the plasticization area (Ly/H ).

In addition, in the following, in the relationship between the rotation angle θ and the bending moment M in the cross section of the beam member 2 shown in FIG. The plasticity rate calculated using the denominator will be described as the yield plasticity rate μy.

In addition, when the plasticity ratio μ is based on the total plastic load, when the plasticity ratio μ becomes 1, the flange portions 3, 4, etc. of the beam member 2 completely yield, and the entire cross section becomes plastic. Therefore, it is not suitable as an indicator indicating a situation where plasticization is progressing, for example, a situation where plasticization is gradually progressing from the surfaces of the flange parts 3 and 4 of the beam member 2. For this reason, the yield plasticity modulus μy defined as described above is used.

Next, regarding the relationship between the plasticization region (Ly/H) and the yield plasticity μy obtained from the results of a constant amplitude repeated loading test in which the loading point of the beam member 2 shown in FIG. 3 is displaced at a constant amplitude, This will be explained with reference to FIGS. 4 to 6.

FIG. 4 is a graph showing the general relationship between the yield plasticity modulus μy and bending moment M obtained from a constant amplitude repeated loading test, and FIG. 6 is a graph showing the general relationship between the number of repetitions N obtained from the loading test and the plasticization region (Ly/H), and FIG. 6 shows the plasticization region (Ly/H) obtained from the graph of FIG. 5. It is a graph showing the relationship between the yield plasticity ratio μy and the yield plasticity ratio μy at a constant amplitude.

In the constant amplitude repeated loading test, the beam member 2 is repeatedly loaded until it breaks so that a predetermined yield plasticity modulus μy is achieved, and multiple strains are applied along the material axis direction (longitudinal direction) of the beam member 2. Strain occurring in the beam member 2 is measured at any time by a strain measurement sensor such as a gauge or an optical fiber provided along the direction of the material axis.

Generally, when the loading point is repeatedly displaced with a constant amplitude, the bending moment M at the end of the beam member 2 gradually increases as the number of repetitions N increases, as shown in FIG. In other words, the plasticized region (Ly/H) of the beam member 2 gradually increases as the number of repetitions N increases.

Here, in the constant amplitude repeated loading test, the area where strain is detected by the strain measurement sensor while the loading point is oscillated once is plasticized when the bending moment M exceeds the yield moment My. It can be regarded as an advanced region, that is, the above-mentioned plasticized region (Ly/H). Therefore, by grasping the size of the plasticized region (Ly/H) based on the detected value of the strain measurement sensor each time the loading point is oscillated once, the number of repetitions N can be adjusted at a predetermined yield plasticity rate μy. Accordingly, it is possible to grasp to what extent the plasticized region (Ly/H) expands.

As shown in Fig. 5, the plasticization region (Ly/H) grasped each time the loading point is oscillated once increases with the number of repetitions N at any yield plasticity ratio μy1, μy2, μy3. However, it tends to gradually approach a constant value. The first yield plasticity ratio μy1 shown in FIG. 5 is when the yield plasticity ratio μy is larger than 1, and the second yield plasticity ratio μy2 is when the yield plasticity ratio μy is larger than the first yield plasticity ratio μy1. The third yield plasticity ratio μy3 indicates a case where the yield plasticity ratio μy is larger than the second yield plasticity ratio μy2.

In addition, the limit number of the number of repetitions N in FIG. 5 is not limited to the number of times until the beam member 2 breaks, but may be any number of times at which no change is recognized in the size of the plasticized region (Ly/H). For example, it may be the number of times until the proof strength of the beam member 2 decreases to about 80 to 90% of the maximum load.

As shown in FIG. ), and the vertical axis is plotted on a graph with the yield plasticity rate μy at a constant amplitude, and an approximate straight line of the plotted points is obtained, a graph of the linear function shown by relational formula A is obtained. .

From the relational expression A that shows the relationship between the range of the plasticization region (Ly/H) and the yield plasticity rate μy at a constant amplitude, it can be seen that the plasticization region (Ly/H) is It is possible to estimate how large H) will ultimately be.

In other words, if the plasticity range Ly of the beam member 2 after the earthquake is understood by the various methods described above, and the size of the beam heir H of the beam member 2 is understood from the drawing etc., based on the relational expression A, Accordingly, it is possible to estimate the yield plasticity modulus μy, which indicates the maximum degree of deformation (amplitude) of the beam member 2 during the earthquake.

In addition, by creating a performance curve (SN curve) shown in Figure 7 from the results of the constant amplitude cyclic loading test, we can use this performance curve and the yield plasticity rate μy during an earthquake estimated from the above relational expression A. It is also possible to estimate the fracture life Nf of the beam member 2 based on . Specifically, the fracture life Nf is generally estimated by the following equation 2.

In the above equation 2, μ is the plasticity modulus, C is a coefficient set depending on the joint type of the beam end, etc., and β is the slope of the evaluation formula, which is experimentally set to a value of about 1/3. be done.

Here, the plasticity modulus μ in the performance curve is based on the total plastic load, and the standard is different from the above-mentioned yield plasticity modulus μy. Therefore, in order to estimate the rupture life Nf based on the performance curve, it is necessary to convert the yield plasticity ratio μy to a plasticity ratio μ.

The conversion factor for converting the yield plasticity modulus μy to the plasticity modulus μ depends on the cross-sectional shape of the beam member 2 and the specific shape of the joint between the beam member 2 and the column member 1, such as the shape of the scallop formed in the web portion 5. etc., and is obtained experimentally or by FEM (Finite Element Method) analysis. The specific size of the conversion coefficient is around 0.7.

Furthermore, since the yield plasticity modulus μy obtained from the relational expression A is the maximum degree of deformation that is estimated to have occurred in the beam member 2 at the time of the earthquake, the rupture life Nf estimated based on the performance curve is actually The value may be smaller than the rupture life of .

Therefore, based on actual seismic waveforms measured at nearby observation points, it is assumed that the yield plasticity rate μy obtained from relational formula A is the maximum value, and multiple yield plasticity rates μy smaller than this are assumed to be the maximum value. By estimating that the beam member 2 was vibrating at , the fracture life Nf evaluated by the linear cumulative damage law (Miner's law) may be calculated.

In addition, by obtaining the number of shaking n (number of vibrations) of the floor of the steel frame building in which the beam member 2 is installed, the degree of damage D of the beam member 2 can be calculated by dividing the number of shaking n by the fracture life Nf. It is also possible to obtain the remaining performance (1-D) and margin (1-D)/D using the damage degree D.

In order to estimate the extent of damage to the beam member 2 (steel member) during an earthquake based on the above characteristics, the earthquake impact evaluation device 10 according to the present embodiment uses a method as shown in FIG. , an acquisition unit 11 that acquires a plasticization range Ly that is the range of the plasticized region of the beam member 2 (steel member), and a yield plasticity of the beam member 2 at the time of an earthquake based on the acquired plasticization range Ly. A calculation unit 12 that calculates the plasticity rate μy (plasticity rate), an evaluation unit 13 that evaluates the influence of the earthquake on the beam member 2 based on the yield plasticity rate μy, and a relational expression used by the calculation unit 12 and the evaluation unit 13. and a storage unit 14 in which calculation results and evaluation results are stored as well as coefficients and the like.

Specifically, the earthquake impact evaluation device 10 is a microcomputer equipped with a CPU (central processing unit), ROM (read only memory), RAM (random access memory), and I/O interface (input/output interface). configured. The RAM stores data for CPU processing, the ROM stores CPU control programs, etc., and the I/O interface connects with the input section 20, display section 30, and measurement section 40 connected to the earthquake impact evaluation device 10. Used for inputting and outputting information. RAM and ROM correspond to the storage section 14. Note that the acquisition unit 11, the calculation unit 12, and the evaluation unit 13 represent each function of the earthquake impact evaluation device 10 as a virtual unit, and do not mean that they physically exist.

The input unit 20 connected to the earthquake impact evaluation device 10 is a keyboard or a touch panel, and is used by an operator to input dimensions and the like related to the plasticization range Ly. The display unit 30 connected to the earthquake impact evaluation device 10 is a monitor screen on which calculation results and evaluation results are displayed, and values input via the input unit 20 are also displayed.

Furthermore, a measurement unit 40 capable of measuring the plasticization range Ly may be connected to the earthquake impact evaluation device 10. The measurement unit 40 is, for example, a device that can measure the detected value of a strain measurement sensor such as a strain gauge or an optical fiber installed along the material axis direction of the beam member 2. Furthermore, the measurement unit 40 may include a vibration recorder that records the number of times n of shaking of the floor where the beam member 2 is provided.

In this way, the earthquake impact evaluation system 100 is constructed by the earthquake impact evaluation device 10 and the equipment connected to the earthquake impact evaluation device 10.

Next, the earthquake impact evaluation method performed by the earthquake impact evaluation device 10 will be described with reference to the flowchart of FIG.

First, in step S11, the acquisition unit 11 acquires the plasticization range Ly, which is the range of the plasticized region of the beam member 2 (steel member). Specifically, the length of the part where the black scale (mill scale) is peeled off and the length of the part where the residual strain is detected by the measurement part 40 are inputted by the operator via the input unit 20 . These input values are acquired by the acquisition unit 11 as the plasticization range Ly. Note that the length of the portion where the residual strain was detected may be directly sent from the measurement unit 40 to the acquisition unit 11 by connecting the measurement unit 40 to the earthquake impact evaluation device 10.

In the subsequent step S12, the calculation unit 12 calculates the yield plasticity ratio μy of the beam member 2 during an earthquake based on the plasticization range Ly acquired by the acquisition unit 11 and the beam stress H stored in advance in the storage unit 14. Ru.

Specifically, using the relational expression A shown in FIG. 6, which was formulated in advance based on the change in the range of the plasticization region (Ly/H) with respect to the number of repetitions N shown in FIG. 5, as described above, From the plasticized region (Ly/H), the yield plasticity ratio μy at the time of the earthquake, which indicates the maximum degree of deformation of the beam member 2 at the time of the earthquake, is calculated. Note that the relational expression A is stored in advance in the storage unit 14.

Next, in step S13, the calculation unit 12 calculates the fracture life Nf (number of repetitions of fracture) until the beam member 2 (steel member) breaks. Specifically, the fracture life Nf of the beam member 2 is calculated using the above equation 2 stored in advance in the storage unit 14.

Note that, as described above, the plasticity ratio μ of the performance curve used in step S13 is based on the total plastic load, and is different from the yield plasticity ratio μy calculated in step S12. Therefore, the yield plasticity ratio μy calculated in step S12 is converted in advance using a conversion coefficient stored in the storage unit 14 in advance.

In the subsequent step S14, the evaluation unit 13 determines the effect of the earthquake on the beam member 2 (steel member) based on the fracture life Nf (number of repetitions of fracture) calculated by the calculation unit 12 and the floor on which the beam member 2 is installed. The evaluation is based on the number of oscillations n.

Specifically, the degree of damage D of the beam member 2 is determined by dividing the number of shakes n by the fracture life Nf, and if the degree of damage D does not exceed 1, the beam member 2 is determined to be sound, When the damage degree D is 1 or more, it is determined that the beam member 2 is not healthy.

The results evaluated by the evaluation unit 13 in this manner are displayed on the display unit 30 and stored in the storage unit 14. Note that the evaluation based on the degree of damage D may indicate not only whether the product is healthy or not, but also the level of damage depending on the magnitude of the value of the degree of damage D.

In order to evaluate the degree of damage D by the evaluation unit 13 in step S14, the number n of tremors during an earthquake in the floor of the steel frame building in which the beam member 2 is installed is transmitted to the input unit 20 or the measurement unit via the acquisition unit 11. 40 is obtained in advance. Note that the evaluation performed by the evaluation unit 13 in step S14 is not limited to one based on the degree of damage D, but may be based on remaining performance (1-D) or margin (1-D)/D. .

In subsequent step S15, the evaluation unit 13 evaluates the influence of the earthquake on the beam member 2 (steel member) based on the yield plasticity rate μy calculated in step S12 and the allowable plasticity preset for each beam member 2. It is evaluated based on the rate μa.

Specifically, the yield plasticity rate μy is compared with the allowable plasticity rate μa, and if the yield plasticity rate μy does not exceed the allowable plasticity rate μa, the beam member 2 is determined to be sound, and the yield plasticity rate μy is If the plasticity rate is greater than or equal to the allowable plasticity μa, it is determined that the beam member 2 is not sound.

The results evaluated by the evaluation unit 13 in this manner are displayed on the display unit 30 and stored in the storage unit 14. Note that the evaluation based on the yield plasticity rate μy and the allowable plasticity rate μa may indicate not only whether the product is sound or not, but also the damage level according to the ratio of the yield plasticity rate μy to the allowable plasticity rate μa. .

The allowable plasticity ratio μa used for evaluation in step S15 may be input via the input unit 20 or may be stored in the storage unit 14 in advance. Note that when the allowable plasticity ratio μa is based on the total plastic load, the yield plasticity ratio μy calculated in step S12 is converted in advance using a conversion coefficient stored in the storage unit 14 in advance.

Through these steps, the earthquake impact evaluation method performed by the earthquake impact evaluation device 10 is completed, and the impact of the earthquake on the beam member 2 is evaluated.

According to the above embodiment, the following effects are achieved.

In the earthquake impact evaluation device 10, the yield plasticity rate μy of the beam member 2 (steel member) during an earthquake is calculated by the calculation unit 12 based on the plasticization range Ly acquired by the acquisition unit 11, and the calculated yield plasticity μy is calculated by the calculation unit 12. Based on the rate μy, the evaluation unit 13 evaluates the damage degree D indicating the effect of the earthquake on the beam member 2 and the ratio of the yield plasticity rate μy to the allowable plasticity rate μa.

In this way, even if the deformation of the beam member 2 (steel member) that occurred during the earthquake is not measured in real time, the extent to which the beam member 2 was affected during the earthquake can be determined based on the plasticization range Ly obtained after the earthquake. By calculating whether or not the beam member 2 has been deformed, it is possible to easily evaluate the influence of the earthquake on the beam member 2 after the earthquake.

Note that the above embodiment assumes a case where a repeated load acts on the beam member 2 (steel member) due to an earthquake, for example, a case where the earthquake is a subduction zone earthquake. On the other hand, in cases where the beam member 2 (steel member) is greatly displaced by a single vibration, as in the case of a direct earthquake, the influence of the earthquake on the beam member 2 can be evaluated after the earthquake using the following method. It is possible to do so.

Generally, in a direct earthquake, unlike a subduction zone earthquake, a single vibration causes a large displacement in the beam member 2 (steel member). Therefore, it is possible to estimate the extent of damage to the beam member 2 during the earthquake based on the results of the monotonic loading test.

Here, since the bending moment M, the yield moment My, and the magnitude of the plasticization range Ly have the relationship shown in the above equation 1, the vertical axis of the graph of FIG. When converted using the beam height H of the beam member 2, the graph shown in FIG. 10 is obtained. Note that in FIG. 10, the horizontal axis is converted to the yield plasticity ratio μy calculated using the yield deformation θy as the denominator.

From the graph shown in FIG. 10, it is possible to estimate the size of the plastic region (Ly/H) when the beam member 2 is displaced at once with what yield plasticity rate μy. It is.

In other words, if the plasticity range Ly of the beam member 2 after a direct earthquake can be ascertained by the various methods described above, and the size of the beam heir H of the beam member 2 can be ascertained from drawings, etc., then the From the relational expression B shown in FIG. 11 obtained by swapping the vertical and horizontal axes of the graph, estimate the yield plasticity rate μy during the earthquake, which indicates the maximum degree of deformation of the beam member 2 during the earthquake. can do. Note that the relational expression B is an approximate curve obtained from a graph obtained by interchanging the vertical and horizontal axes of the graph in FIG.

By comparing the yield plasticity ratio μy calculated in this way with the allowable plasticity ratio μa preset for each beam member 2, it is possible to determine the impact can be assessed.

The graph shown in FIG. 11 has the same vertical and horizontal axes as the graph shown in FIG. 6, and the graph shown in FIG. In contrast to the graph shown in Figure 11, which shows the yield plasticity rate μy in a state close to shaking, the graph shown in Figure 11 shows the yield plasticity rate μy under monotonous loading, that is, in a state close to shaking caused by a direct earthquake. The yield plasticity modulus μy is shown.

Therefore, in the case of a combined trench-type and subduction-type earthquake, the yield plasticity rate μy at the time of the earthquake estimated from the relational expression A, and the yield plasticity rate μy at the time of the earthquake estimated from the relational formula B. The influence of the earthquake on the beam member 2 (steel member) may be evaluated based on the yield plasticity ratio μy calculated by adding the ratios together at an arbitrary ratio.

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. do not have.

10...Earthquake impact evaluation device 2...Beam member (steel member)
11... Acquisition unit 12... Calculation unit 13... Evaluation unit

Claims (5)

An earthquake impact evaluation device that evaluates the impact of an earthquake on steel members constituting a steel frame building,
an acquisition unit that acquires the range of the plasticized region of the steel member;
a calculation unit that calculates the plasticity rate of the steel member during an earthquake based on the range of the plasticization region;
an evaluation unit that evaluates the impact of an earthquake on the steel member based on the plasticity ratio;
Earthquake impact evaluation device. The calculation unit calculates the plasticity rate using a relational expression between the range of the plasticity area and the plasticity rate at a constant amplitude, which is established in advance based on a change in the range of the plasticity area with respect to the number of repetitions.
The earthquake impact evaluation device according to claim 1. The acquisition unit further acquires the number of vibrations of the steel frame building during an earthquake,
The calculation unit calculates the number of ruptures until the steel member breaks based on the plasticity rate,
The evaluation unit evaluates the impact of the earthquake on the steel member based on the number of repeated fractures and the number of vibrations.
The earthquake impact evaluation device according to claim 1 or 2. The acquisition unit further acquires an allowable plasticity modulus of the steel member,
The evaluation unit evaluates the impact of the earthquake on the steel member based on the plasticity rate and the allowable plasticity rate.
The earthquake impact evaluation device according to claim 1 or 2. An earthquake impact evaluation method for evaluating the impact of an earthquake on steel members constituting a steel frame building, the method comprising:
obtaining the range of the plasticized region of the steel member;
calculating the plasticity rate of the steel member during an earthquake based on the range of the plasticization region;
evaluating the impact of the earthquake on the steel member based on the plasticity ratio;
Earthquake impact assessment method.