Earthquake information distribution system and earthquake information distribution method

Abstract

To provide an earthquake information distribution system etc. that can realize evacuation taking into consideration the impact of damage to buildings. [Solution] The earthquake information distribution system includes a receiving unit that receives emergency earthquake alerts distributed by the Japan Meteorological Agency, a prediction unit that, when the emergency earthquake alert is received, calculates a predicted value of the seismic intensity at a specified location based on the emergency earthquake alert, an evaluation unit that predicts the response spectrum of a building at the specified location based on the emergency earthquake alert and performs a damage assessment of the building based on the predicted response spectrum results, and a distribution unit that distributes earthquake information including information regarding evacuation instructions based on the damage assessment to terminals at specified locations where the predicted value of the seismic intensity exceeds a threshold, and the evaluation unit calculates the response spectrum of the building using a response calculation model based on the observation results of a seismometer installed in the building, and performs a damage assessment of the building again based on the calculated response spectrum results.

Description

[Technical Field]

[0001] The present invention relates to an earthquake information distribution system and an earthquake information distribution method. [Background technology]

[0002] The current Earthquake Early Warning System (Advanced Use: Forecast) is a system that notifies receivers of the epicenter and magnitude of an earthquake when it occurs. Receivers use the epicenter and magnitude, as well as the ground amplification factor at the receiving location, to estimate the arrival time and seismic intensity of the S-waves, and then notify people at the receiving location of the information. Depending on the magnitude of the seismic intensity, the system can guide evacuation, opening and closing doors, turning power on and off, and other evacuation actions, making it useful for disaster prevention. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-37516 Summary of the Invention [Problem to be solved by the invention]

[0004] In the event of a large earthquake, it is necessary to consider whether the building structure will be damaged when evacuating, and it is therefore important to check the condition of the building even after the earthquake. For important buildings such as base buildings, it is thought that safety can be improved by being able to evaluate the safety of the structural frame at the time of receiving an earthquake early warning. The present invention was made to solve this problem. [Means for solving the problem]

[0005] (1) The present invention relates to an earthquake information distribution system including a receiving unit that receives an Earthquake Early Warning distributed by the Japan Meteorological Agency; a prediction unit that, when the Earthquake Early Warning is received, calculates a predicted value of seismic intensity at a predetermined location based on the Earthquake Early Warning; an evaluation unit that predicts a response spectrum of a building at the predetermined location based on the Earthquake Early Warning and performs a damage assessment of the building based on the predicted response spectrum; and a distribution unit that distributes earthquake information including information on evacuation instructions based on the damage assessment to a terminal located at a predetermined location where the predicted value of the seismic intensity exceeds a threshold, wherein the evaluation unit calculates the response spectrum of the building using a response calculation model based on the observation results of a seismometer installed in the building, and re-evaluates the damage of the building based on the calculation result of the response spectrum.

[0006] The present invention also relates to an earthquake information distribution method including a receiving step of receiving an Earthquake Early Warning distributed by the Japan Meteorological Agency, a prediction step of calculating a predicted value of seismic intensity at a predetermined location based on the Earthquake Early Warning when the Earthquake Early Warning is received, an evaluation step of predicting a response spectrum of a building at the predetermined location based on the Earthquake Early Warning and performing a damage assessment of the building based on the predicted response spectrum, and a distribution step of distributing earthquake information including information regarding evacuation instructions based on the damage assessment to a terminal at a predetermined location where the predicted value of the seismic intensity exceeds a threshold, wherein the evaluation step calculates the response spectrum of the building using a response calculation model based on the observation results of a seismometer installed in the building, and re-evaluates the damage of the building based on the calculation result of the response spectrum.

[0007] (2) In the earthquake information distribution system and earthquake information distribution method according to the present invention, the evaluation unit (in the evaluation step) may predict the response spectrum of the ground surface at the specified location based on the Earthquake Early Warning, predict the response spectrum of each floor of the building based on the predicted result of the ground surface response spectrum and a transfer function from the ground surface to each floor of the building, and perform a damage assessment of the building based on the predicted result of the response spectrum of each floor.

[0008] (3) In the earthquake information distribution system and earthquake information distribution method according to the present invention, the evaluation unit (in the evaluation step) may predict the maximum ground acceleration or maximum ground velocity at the specified location and the response spectrum of the building based on the Earthquake Early Warning, and may perform a damage assessment of the building based on the predicted results of the maximum ground acceleration or maximum ground velocity and the predicted results of the response spectrum.

[0009] (4) In the earthquake information distribution system and earthquake information distribution method according to the present invention, the evaluation unit (in the evaluation step) may update the response calculation model by resetting the rigidity of the building based on the observation results of a first seismometer installed in the foundation of the building and a second seismometer installed on the roof of the building.

[0010] (5) In the earthquake information distribution system and earthquake information distribution method according to the present invention, the evaluation unit (in the evaluation step) may determine whether the natural period of the building has changed based on the observation results of the first seismometer and the second seismometer, and may reset the stiffness if the natural period has changed.

[0011] (6) In the earthquake information distribution system and earthquake information distribution method according to the present invention, when the Earthquake Early Warning is received, the prediction unit (in the prediction step) may calculate a predicted value of long-period ground motion having a period corresponding to the natural period of the building at the specified location based on the Earthquake Early Warning, and the distribution unit (in the distribution step) may distribute the earthquake information to a terminal at a specified location where the predicted value of the seismic intensity or the long-period ground motion exceeds a threshold value. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing an example of the configuration of an earthquake information distribution system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram illustrating an example of a functional block diagram of a server. [Figure 3] 10 is a flowchart for a short period showing the processing flow of the earthquake information distribution system of this embodiment. [Figure 4]10 is a flowchart for a short period showing the processing flow of the earthquake information distribution system of this embodiment. [Figure 5] FIG. 10 is a diagram showing an example of a damage assessment table that stores damage conditions and evacuation locations corresponding to measured seismic intensity. [Figure 6] FIG. 10 is a diagram showing an example of a fragility curve showing the probability of damage occurrence as a function of the peak value of the pseudo velocity response spectrum. [Figure 7] 10 is a flowchart for a long period showing the flow of processing of the earthquake information distribution system of this embodiment. [Figure 8] 10 is a flowchart for a long period showing the flow of processing of the earthquake information distribution system of this embodiment. [Figure 9] A diagram showing an example of a damage assessment table that stores damage and damage status and evacuation locations corresponding to the long-period class of a building and the long-period seismic motion class. [Figure 10] FIG. 10 is a diagram showing an example of earthquake information notification delivered to a terminal. [Figure 11] FIG. 10 is a diagram showing an example of earthquake information notification delivered to a terminal. [Figure 12] FIG. 10 is a diagram showing an example of earthquake information notification delivered to a terminal. [Figure 13] FIG. 10 is a diagram showing an example of earthquake information notification delivered to a terminal. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described. Note that the embodiments described below do not unduly limit the content of the present invention described in the claims. Furthermore, not all of the configurations described in the present embodiments are necessarily required constituent elements of the present invention.

[0014] 1. Configuration 1 is a diagram showing an example of the configuration of an earthquake information distribution system according to this embodiment. The earthquake information distribution system 1 includes a server 10 and a plurality of terminals 20.

[0015] The server 10 is connected via a dedicated line 3 to the server of a distributor 2 (for example, the Japan Meteorological Agency's Japan Meteorological Agency) that distributes emergency earthquake warnings, receives the data on the emergency earthquake warnings distributed from the server of the distributor 2, predicts the seismic intensity (the strength of short-period seismic motion and long-period seismic motion) and the arrival time of the seismic motion, and distributes earthquake information to the terminal 20 via a network 4 (such as the Internet).

[0016] Terminal 20 is a terminal located at a plurality of predetermined locations (buildings such as commercial facilities, schools, hospitals, factories, etc.) to which earthquake information is distributed, and is, for example, a mobile terminal such as a smartphone carried by an employee or related person at the predetermined location, or a PC located at the predetermined location. Terminal 20 receives the earthquake information distributed from server 10 and displays the information included in the earthquake information on a display unit (display).

[0017] 2 is an example of a functional block diagram of the server 10. The server 10 includes a processing unit 100, a communication unit 110, and a storage unit 120.

[0018] The communication unit 110 performs various controls for communicating with the terminal 20 and the server of the distributor 2, and its functions can be realized by hardware such as various processors or communication ASICs, programs, and the like.

[0019] The memory unit 120 stores programs and various data for causing the computer to function as each component of the processing unit 100, and also functions as a work area for the processing unit 100. This function can be realized by a hard disk, memory, or the like. The memory unit 120 stores location information (latitude and longitude) of multiple predetermined locations, the ground amplification factor of the predetermined locations, information such as the transfer function and natural period of the building at the predetermined location, and data (damage assessment tables and damage assessment graphs) specifying the relationship between seismic intensity, response spectrum, and damage status. The ground amplification factor for a predetermined location is determined by using the ground amplification factor for the area including the location in the 500m mesh topography classification data of the National Research Institute for Earth Science and Disaster Resilience, or by using the ground amplification factor estimated based on the average S-wave velocity from the surface to 30m underground. The average S-wave velocity is determined by using the results of the Matsuoka-Midorikawa equation, which is estimated based on in-situ PS logging results, microtopography classification, elevation, distance from major rivers, and other factors.

[0020] The processing unit 100 performs various processes using the storage unit 120 as a work area. The functions of the processing unit 100 can be realized by hardware such as various processors (CPU, DSP, etc.) and programs. The processing unit 100 includes a receiving unit 101, a predicting unit 102, an evaluating unit 103, and a distributing unit 104.

[0021] The receiving unit 101 receives the data of the Earthquake Early Warning distributed from the server of the distributor 2. The data of the Earthquake Early Warning includes the time of occurrence of the earthquake, the location of the epicenter (latitude, longitude, and depth), and the scale of the earthquake (Japan Meteorological Agency magnitude).

[0022] When an Earthquake Early Warning is received, the prediction unit 102 calculates a predicted value of seismic intensity (predicted seismic intensity) and a predicted value of arrival time of seismic motion for each predetermined location based on the received Earthquake Early Warning data and the location information and ground amplification factor of the predetermined location stored in the memory unit 120. Furthermore, the prediction unit 102 calculates a predicted value of long-period ground motion (long-period ground motion scale) of a period corresponding to the natural period of the building for each predetermined location based on the received Earthquake Early Warning data, the location information of the predetermined location stored in the memory unit 120, and information on the natural period of the building at the predetermined location. The period corresponding to the natural period of the building may be the natural period of the building itself, or a period around the natural period.

[0023] The evaluation unit 103 predicts the maximum ground acceleration or maximum ground velocity at a predetermined location and the response spectrum (pseudo velocity response spectrum) of the building at the predetermined location based on the Earthquake Early Warning, and performs damage assessment on the building based on the predicted results of the maximum ground acceleration or maximum ground velocity, the predicted results of the response spectrum, and a damage assessment table or a damage assessment graph. Here, the evaluation unit 103 may predict the response spectrum of the ground at the predetermined location based on the Earthquake Early Warning, predict the response spectrum of each floor of the building based on the predicted result of the ground response spectrum and a transfer function from the ground to each floor of the building, and perform damage assessment on the building based on the predicted results of the response spectrum of each floor, the predicted results of the maximum ground acceleration or maximum ground velocity, and a damage assessment table or a damage assessment graph. Furthermore, after the earthquake arrives, the evaluation unit 103 calculates the response spectrum of the building using a response calculation model based on the observation results of a seismometer (acceleration sensor) installed on the building, and performs damage assessment on the building again based on the calculated response spectrum and the damage assessment table or the damage assessment graph. Here, the evaluation unit 103 may reset the stiffness of the building based on the observation results of a first seismometer installed in the foundation of the building and a second seismometer installed on the roof of the building, update the response calculation model, and perform damage assessment of the building again based on the observation results using the updated response calculation model.The evaluation unit 103 may determine whether the natural period of the building has changed based on the observation results of the first seismometer and the second seismometer, and reset the stiffness of the building if the natural period has changed.

[0024] The distribution unit 104 distributes earthquake information to terminals 20 located at predetermined locations where the predicted value of seismic intensity (or long-period ground motion) has exceeded a threshold. The earthquake information includes the seismic intensity (and long-period ground motion) and arrival time predicted by the prediction unit 102, and information regarding evacuation instructions based on the damage assessment performed by the evaluation unit 103.

[0025] 2. Processing Next, an example of the processing of the earthquake information distribution system (server 10) of this embodiment will be described with reference to the flowcharts of FIGS.

[0026] 3 and 4 are flowcharts for a short period used when the natural period of a building at a predetermined location is 1 second or less. Steps S10 to S14 are processes performed before the system is introduced to predict seismic intensity taking building characteristics into account. If the building at the predetermined location is a building of high importance (such as a disaster prevention base or a place where many people gather) (Y in step S10) and there are publicly available observation records of earthquakes (K-NET, KiK-net, S-net, etc.) within 500 meters of the building's construction site (Y in step S11), the prediction unit 102 performs a simulation analysis of the building using the observation records (for example, earthquake response analysis using a mass point system simulation) to determine a value equivalent to the measured seismic intensity of the building (building measured seismic intensity BI), and compares the average of the building measured seismic intensity BI with the measured seismic intensity of the observation records (observed measured seismic intensity OI) (step S12). If the difference (BI-OI) between the average of the building measured seismic intensity BI and the average of the observed measured seismic intensity OI is 0.3 or more (Y in step S13), the prediction unit 102 stores the difference as an incremental measured seismic intensity in the memory unit 120 in association with the building (specified location) (step S14).

[0027] The receiving unit 101 receives the Earthquake Early Warning data distributed from the server of the distributor 2 (step S15). Next, the prediction unit 102 predicts the alarm measurement seismic intensity MI and the arrival time of the seismic motion for each predetermined location based on the Earthquake Early Warning data received by the receiving unit 101 and the location information and ground amplification information of the predetermined location stored in the memory unit 120 (step S16).

[0028] The method for predicting the alarm instrumental seismic intensity MI will be explained below. First, the shortest fault distance X (km) is calculated using the following formula:

[0029] X=S0-L / 2

[0030] However, the minimum value of X is 3 km. Here, S0 is the distance from the target point (predetermined location) to the epicenter (epicenter distance), and can be calculated from the location of the epicenter (latitude, longitude, and depth) included in the Earthquake Early Warning and the location of the predetermined location (latitude and longitude). Furthermore, L is the fault length, and can be calculated from the moment magnitude Mw using the following formula.

[0031] logL=0.5Mw-1.85

[0032] The moment magnitude Mw can be converted from the Japan Meteorological Agency magnitude Mj included in the Earthquake Early Warning using the following formula:

[0033] Mw=Mj-0.171

[0034] Next, the maximum ground surface velocity amplitude PGV (cm / s) of S waves at a given location is calculated using the following equation:

[0035] PGV=ARV 600 ×PGV 600

[0036] Here, ARVs 600 is the ground amplification factor at a given location, which can be calculated using the following formula:

[0037] log(ARV 600 )=1.83-0.66log(AVS)±σ (100 <AVS<1500)

[0038] Here, AVS is the average S-wave velocity from the surface to 30m underground (if AVS is less than 100m / s, it is evaluated at an average S-wave velocity of 100m / s). σ is not used in the calculation. For AVS, if PS logging results are available for the target location, those results are used; if there are no PS logging results, AVS is estimated using the following formula.

[0039] Log(AVS)=a+b・log(H)+c・log(D)±δ

[0040] Here, H is the elevation, D is the distance from the main river (km), δ is not used in the calculation, and a, b, and c are coefficients according to the microtopography classification shown in Table 1.

[0041] [Table 1] If the PS logging results or estimation formula cannot be used for the average S-wave velocity AVS, the ground amplification factor ARV can be calculated from the 500m mesh topographic classification data of the National Research Institute for Earth Science and Disaster Prevention. 600 Ask for.

[0042] PGV 600 is the maximum velocity amplitude (cm / s) of earthquake motion on hard ground at a specified location where the propagation velocity of S waves is equivalent to 600 m / s, and can be calculated using the following formula:

[0043] Log(PGV 600 )=0.58Mw+0.0038d-1.29-log(X+0.0028×10 0.50Mw )-0.002X

[0044] Here, d is the depth (km) of the epicenter included in the Earthquake Early Warning.

[0045] The measured seismic intensity I of short-period earthquake motion at a given location can be calculated using the following formula:

[0046] I=2.68+1.72log(PGV)

[0047] If an incremental measured seismic intensity (BI-OI) is stored in association with a specified location (building), the value obtained by adding the incremental measured seismic intensity to the measured seismic intensity I is used as the warning measured seismic intensity MI, and if an incremental measured seismic intensity is not stored, the measured seismic intensity I is used as the warning measured seismic intensity MI.

[0048] The method for predicting the arrival time (arrival time) of seismic motion is explained below. First, the epicentral distance l0 (km) is calculated from the hypocenter location (latitude and longitude) included in the Earthquake Early Warning and the location (latitude and longitude) of the point to be predicted (predetermined location). Next, using the calculated epicentral distance l0 and the hypocenter depth d included in the Earthquake Early Warning, the travel time at the closest epicentral distance and hypocenter depth is calculated from the JMA2001 travel time table provided by the Japan Meteorological Agency. Because the travel time given in the travel time table is a mesh-like value, it is interpolated in both directions for the epicentral distance and hypocenter depth to determine the travel time corresponding to l0 and d. The calculated travel time is added to the occurrence time of the earthquake included in the Earthquake Early Warning to determine the arrival time at the specified location.

[0049] Next, the distribution unit 104 determines the distribution content of the earthquake information ( The distribution unit 104 distributes earthquake information including the predicted alarm instrumental seismic intensity MI for a predetermined location and the arrival time (arrival time, or margin time which is the difference between the arrival time and the current time) to the terminals 20 at the predetermined location if the predicted alarm instrumental seismic intensity MI for the predetermined location is less than 4.0 (step S18). If the terminals 20 are mobile terminals equipped with a positioning function, the distribution unit 104 identifies the terminals 20 at the predetermined location based on the location information acquired from each terminal 20.

[0050] Furthermore, if the predicted alarm instrumental seismic intensity MI for a predetermined location is equal to or greater than 4.0 and less than 5.5, the distribution unit 104 distributes earthquake information, including the predicted alarm instrumental seismic intensity MI for the predetermined location and its arrival time, and information regarding an evacuation order, as an evacuation warning to the terminal 20 at the predetermined location (step S19). For evacuation instructions, a location outside the building or a safe location may be identified and presented as an evacuation location depending on the margin of time. Damage assessment of the building may also be performed based on the alarm instrumental seismic intensity MI for the predetermined location (building) and a damage assessment table or damage assessment graph for the building, and information regarding an evacuation order may be generated based on the damage assessment. In this case, a damage assessment table, such as that shown in FIG. 5, is created as a database in tabular form that lists damage status (damage to the structural frame (columns, beams, etc.) and interior (major damage, moderate damage, minor damage), fallen ceilings, relocated furniture, etc.) and evacuation locations (evacuation memos) corresponding to the measured seismic intensity. The damage assessment table is then referenced to identify the damage status and evacuation location corresponding to the alarm instrumental seismic intensity MI calculated in step S16. In addition, as a damage assessment graph, a fragility curve showing the probability of damage occurrence as a function of the measured seismic intensity may be created for each damage situation, and by referring to the damage assessment graph, the occurrence of damage whose occurrence probability corresponding to the alarm measured seismic intensity MI obtained in step S16 exceeds a predetermined value may be predicted.

[0051] If the predicted warning measured seismic intensity MI for a specified location is 5.5 or more, the distribution unit 104 determines whether the difference (margin time) between the predicted arrival time and the current time is 30 seconds or more (step S20), and if the margin time is less than 30 seconds (N in step S20), distributes earthquake information including the predicted warning measured seismic intensity MI for the specified location, the arrival time, and information regarding evacuation instructions to the terminal 20 at the specified location as an evacuation warning (step S19).

[0052] If the predicted alarm instrumental seismic intensity MI for a predetermined location is 5.5 or greater and the margin of time is 30 seconds or greater (Y in step S20), the evaluation unit 103 predicts the maximum ground acceleration PGA or maximum ground velocity PGV for the predetermined location based on the Earthquake Early Warning data and the response spectrum of the building at the predetermined location, and performs a damage assessment of the building (steps S21 to S24). It is desirable to perform damage assessment using PGA if the natural period of the building is 1 second or less, and PGV if it is greater than 1 second, but if similar buildings have been evaluated based on data from past earthquakes, the PGA or PGV index used there is used.

[0053] The maximum ground acceleration PGA is calculated using the same formula as the maximum ground velocity PGV (maximum ground velocity amplitude) calculated when predicting the seismic intensity I. The shortest fault distance X is calculated from the epicenter distance SO and the fault length L, and the maximum ground acceleration amplitude PGA (cm / s 2 ) is calculated by the following equation (step S21).

[0054] PGA=ARV 600 ×PGA 600

[0055] Here, ARVs 600 is the ground amplification factor at a given location as described above. 600 is the maximum acceleration amplitude (cm / s) of earthquake motion on hard ground at a given location, where the propagation velocity of S waves is equivalent to 600 m / s. 2 ) and can be calculated using the moment magnitude Mw, the depth of the epicenter d, and the shortest fault distance X using the following formula:

[0056] Log(PGA 600 )=0.50Mw+0.0043d+0.61-log(X+0.0055×10 0.50Mw )-0.003X

[0057] The response spectrum of a building is calculated as follows: First, the evaluation unit 103 calculates the response spectrum G0pSv of the ground surface at a predetermined location using the following equation (step S22): The spectrum calculation period is set to a range of, for example, 0.1 seconds to 10 seconds.

[0058] G0pSv=MHVR×KipSv

[0059] Here, MHVR is the Fourier amplitude ratio of horizontal to vertical motion (microtremor H / V spectrum ratio) obtained from microtremor data measured in advance on the ground surface at a specified location. Also, kipSv is the pseudo velocity response spectrum of the engineering bedrock at a specified location, calculated using the following formula:

[0060] kipSv=S A / ω

[0061] where S A is the acceleration response spectrum expressed by the following equation (Morikawa-Fujiwara earthquake motion prediction formula), and ω (ω=2π / T, T is the natural period) is the natural angular frequency.

[0062] log 10 S A =a·(Mw'-16) 2 +b k X+c k -log 10 (X+d·10 0.5Mw’ )+G d +G s +AI+PH+ρ where Mw'=min(Mw,8.2)

[0063] where a, b k ,c k , d are regression coefficients. The subscript k indicates the earthquake type: 1 for intracrustal earthquakes, 2 for interplate earthquakes, and 3 for intraplate earthquakes. G d is the correction term for deep soil, G sis a correction term for shallow ground, AI is a correction term for anomalous seismic zones, PH is a correction term for intraplate earthquakes on the Philippine Sea Plate, and ρ is the standard deviation. The moment magnitude Mw and shortest fault distance X are calculated based on Earthquake Early Warning data (epicenter location, Japan Meteorological Agency magnitude Mj), and other parameters use publicly available data such as J-SHIS.

[0064] Next, the evaluation unit 103 multiplies the ground response spectrum G0pSv by the transfer function (Fi / GF) from the ground (first floor) to each floor (i floor) of the building to obtain the response spectrum FipSv for each floor of the building at a predetermined location (step S23). The transfer function (Fi / GF) is the ratio of the Fourier amplitude (Fi) of the i floor to the Fourier amplitude (GF) of the first floor, and is evaluated in advance by calculating the building response using a random phase signal wave. Note that if the building foundation is deeply embedded or the ground is soft, the transfer function of the input loss NSO (1st floor foundation / ground surface) is obtained in advance using FEM, and the response spectrum FipSv for each floor of the building is obtained by multiplying G0pSv by NSO, i.e., G0pSv × NSO, by the transfer function (Fi / GF).

[0065] Next, the evaluation unit 103 performs a damage assessment of the building based on the peak ground acceleration PGA or peak ground velocity PGV, the response spectrum FipSv of each floor of the building, and a damage assessment table or damage assessment graph of the building (step S24). For example, a database is created as a damage assessment table, which lists the damage status (damage to the structural frame (columns, beams, etc.) and interior (major damage, moderate damage, minor damage), falling ceiling, movement of fixtures, entrapment in elevators) corresponding to the response spectrum FipSv (peak value) of each floor and the safe evacuation locations at that time in tabular form, and the damage assessment table is referenced to identify the damage status and evacuation locations corresponding to the response spectrum FipSv (peak value) calculated in step S23. 6, a fragility curve showing the probability of occurrence of damage as a function of the pseudo velocity response spectrum pSv (peak value) may be created for each damage situation, and the occurrence of damage where the occurrence probability corresponding to the response spectrum FipSv (peak value) calculated in step S23 exceeds a predetermined value (for example, 50%) may be predicted by referring to the damage assessment graph. The evaluation of pSv (peak value) involves the natural period of the building, and so it is possible to predict the occurrence of damage where the occurrence probability corresponding to the response spectrum FipSv (peak value) calculated in step S23 exceeds a predetermined value (for example, 50%). For damage assessment, peak values ​​within ±20% of the building's natural period may be used, and for ceilings, this may be combined with PGA. Depending on the damage assessment target, a more highly correlated value may be selected by combining the period with pSv, PGA, or PGV, as appropriate. For damage assessment, PGA or PGV has been evaluated for the entire building based on past earthquakes, so the first step is to use PGA or PGV evaluation as a reference. For example, if the probability of damage occurrence based on PGA or PGV is minor and above 5%, the next step is to evaluate using FipSv to prevent the maximum value of the ground surface response spectrum G0pSv from being generated by impulsive waves. If there is a large difference between the PGA, PGV, and FipSv evaluations, the PGA or PGV results may also be included in the comments.

[0066] For a given location (building) where the microtremor H / V spectral ratio (MHVR) or the transfer function (Fi / GF) for each floor have not been evaluated in advance and the response spectrum FipSv cannot be predicted, steps S22 and S23 are omitted, and damage assessment is performed in step S24 based on the alarm instrumental seismic intensity MI and a damage assessment table or damage assessment graph. In this case, the damage status and evacuation location corresponding to the alarm instrumental seismic intensity MI calculated in step S16 are identified by referring to a damage assessment table, such as that shown in FIG. 5, which stores the damage status and evacuation location (evacuation memo) corresponding to the instrumental seismic intensity MI. Furthermore, the occurrence of damage whose occurrence probability corresponding to the alarm instrumental seismic intensity MI calculated in step S16 exceeds a predetermined value may be predicted by referring to a fragility curve (damage assessment graph) for each damage status, which shows the probability of damage occurrence as a function of the instrumental seismic intensity. Of course, PGA or PGV can be used instead of the alarm instrumental seismic intensity MI.

[0067] Next, the distribution unit 104 distributes earthquake information including the predicted warning instrumental seismic intensity MI and arrival time for the predetermined location and information on evacuation instructions based on the damage assessment as an evacuation warning to the terminal 20 located in the predetermined location (building where the predicted warning instrumental seismic intensity MI is 5.5 or more) (step S25). As the evacuation instructions, safe locations are identified for each area based on the damage assessment in step S24 and presented as evacuation locations.

[0068] After the earthquake arrives, the evaluation unit 103 determines whether the natural period of a building at a predetermined location (a building with a predicted alarm seismic intensity MI of 5.5 or higher) has changed based on the observation results (seismic wave records) from a first seismometer installed in the foundation of the building and a second seismometer installed on the roof of the building (step S26). Here, the natural frequency is calculated from the peak value of the ratio (transfer function of RF / 1F) of the Fourier amplitude (RF) of the acceleration waveform observed by the second seismometer to the Fourier amplitude (1F) of the acceleration waveform observed by the first seismometer, and the natural period, which is the reciprocal of the natural frequency, is compared with the natural period previously evaluated before the earthquake occurred. If the natural period of the building has not changed since before the earthquake (N in step S26), the evaluation unit 103 calculates the response spectrum for each floor of the building using a response calculation model (a mass point model in which each floor of the building is modeled with mass and stiffness) based on the observation results of the first seismometer (step S28). Then, based on the response spectrum calculation results and the damage assessment table or damage assessment graph of the building, the evaluation unit 103 performs a damage assessment of the building again to identify the damage state (step S29). The accuracy of the prediction can be confirmed by comparing the response spectrum calculated in step S28 with the response spectrum FipSv predicted in step S23. If the natural period of the building has changed since before the earthquake (Y in step S26), the evaluation unit 103 updates the response calculation model by redefining the stiffness distribution of the building by Bayes' theorem based on the observation results of the first and second seismometers (Bayesian update) (step S27), and executes the processing of step S28 using the updated response calculation model. Here, by comparing the rooftop response acceleration (maximum value, frequency characteristics, phase) calculated in step S28 with the response acceleration obtained from the observation results of the second seismometer, the accuracy of the stiffness identification in step S27 can be confirmed, and re-identification may be performed if necessary. In addition, the transfer function (Fi / GF) used to predict the response spectrum FipSv in step S23 may be updated based on the stiffness distribution identified in step S27.

[0069] The results of the damage assessment in step S29 are displayed, for example, on the terminal of the building manager. If the results of the damage assessment indicate that it is necessary to directly confirm the damage, the manager will check the damage status, and if repairs are necessary, they will carry out repair work, etc. Note that if a second seismometer is not installed in a building at a specified location (a building with a predicted alarm instrumental seismic intensity MI of 5.5 or higher), the processes of steps S26 and S27 are omitted. Also, if a seismometer is not installed in the building, and there are publicly available observation records of earthquakes within 500 m of the building's construction site, in step S28, the response spectrum of each floor of the building is calculated using a response calculation model based on the observation records.

[0070] 7 and 8 are flowcharts for long periods used when the natural period of a building at a given location is greater than 1 second. Note that explanations of processes similar to those in the flowcharts for short periods in Figs. 3 and 4 will be omitted where appropriate.

[0071] In step S36, the prediction unit 102 predicts the long-period ground motion scale based on the alarm measurement seismic intensity MI and the arrival time of the seismic motion, as well as the data of the emergency earthquake warning received by the receiving unit 101, the location information of the specified location stored in the memory unit 120, and the information on the natural period of the building at the specified location.

[0072] The method for predicting long-period ground motion scales is explained below. First, the absolute velocity response spectrum Sva(T) for period T is calculated using the following formula. Period T is a value between 1.6 and 7.8 seconds in 0.2-second intervals, and Sva(T) is calculated for each period.

[0073] Log 10 Sva(T)=c(T)+a(T)Mj-log 10 Rb(T)R+siteFactor(T)

[0074] Here, Mj is the Japan Meteorological Agency magnitude included in the Urgent Earthquake Information. Also, R is the distance from a predetermined location to the earthquake source (source distance), which can be obtained from the location of the earthquake source (latitude, longitude, and depth) included in the Urgent Earthquake Information and the location of the predetermined location (latitude and longitude). Further, c(T), a(T), and b(T) are constants or coefficients corresponding to the period T. Also, siteFactor(T) is a correction value corresponding to the period T for each point to be predicted. As the correction value, a correction value based on observational records (a correction value statistically obtained from the actual observed values at each observation point) or a correction value based on the deep ground structure (a correction value calculated from the depth of the upper surface of the S-wave velocity 1.4 km / s layer of the J-SHIS deep ground structure model) can be used.

[0075] Next, the absolute velocity response spectrum Sva(T) is converted into class values to obtain the long-period ground motion class LS. The long-period ground motion class LS is such that when the maximum value of Sva(T) over all periods is 5 cm / s or more and less than 15 cm / s, it is class "1"; when the maximum value is 15 cm / s or more and less than 50 cm / s, it is class "2"; when the maximum value is 50 cm / s or more and less than 100 cm / s, it is class "3"; and when the maximum value is 100 cm / s or more, it is class "4".

[0076] In step S36, in addition to the long-period ground motion class LS, the building's long-period class BS considering the natural period Tb of the building at a predetermined location is obtained. The building's long-period class BS is such that when the maximum value of the absolute velocity response spectrum Sva(T) at a period T (0.8Tb < T < 1.2Tb) around the natural period Tb is less than 20 cm / s, it is class "1"; when the maximum value is 20 cm / s or more and less than 50 cm / s, it is class "2"; and when the maximum value is 50 cm / s or more, it is class "3".

[0077] In step S37, the distribution unit 104 distributes (issues) the content of the earthquake information according to the predicted warning measurement seismic intensity MI, the long-period ground motion class LS, and the building's long-period class BS. The distribution unit 104 determines that for a predetermined location, when the predicted warning measurement seismic intensity MI is 4.0 or more and 5.5 If the predicted seismic intensity for the predetermined location is less than 5.5, the long-period seismic intensity for the building is 2, or the long-period ground motion scale is 3, the earthquake information including the predicted alarm instrumental seismic intensity MI and arrival time for the predetermined location and information on an evacuation order is distributed as an evacuation warning to terminal 20 at the predetermined location (step S39). If the predicted alarm instrumental seismic intensity for the predetermined location is MI 5.5 or more, the long-period scale for the building is 3, or the long-period ground motion scale is LS 4, and the margin of time is less than 30 seconds (N in step S40), the process proceeds to step S39. If the margin of time is 30 seconds or more (Y in step S40), the evaluation unit 103 predicts the peak ground acceleration PGA or peak ground velocity PGV for the predetermined location and the response spectrum of the building at the predetermined location based on the Earthquake Early Warning data, and performs a damage assessment of the building (steps S41 to S44).

[0078] In step S42, the evaluation unit 103 calculates the response spectrum G0pSv of the ground surface at a predetermined location. For the range of 0.1 to 10 seconds of the spectrum calculation period, G0pSv is calculated by multiplying the microtremor H / V spectral ratio (MHVR) by the pseudo velocity response spectrum kipSv of the engineering bedrock, as in step S22, for the range of 0.1 to 1.6 seconds, and for the range of 1.6 to 10 seconds, G0pSv is calculated by multiplying the microtremor H / V spectral ratio (MHVR) by the absolute velocity response spectrum Sva(T). However, siteFactor(T) in the formula for Sva(T) is set to 0.

[0079] In step S44, the evaluation unit 103 performs damage assessment based on the response spectrum FipSv for each floor of the building and the damage assessment table or damage assessment graph, as well as based on the long-period ground motion class LS, the building's long-period class BS, and the damage assessment table or damage assessment graph. In this case, the evaluation unit 103 refers to a damage assessment table, as shown in FIG. 9, which stores the damage and damage status and evacuation locations (evacuation memos) corresponding to the long-period ground motion class LS and the building's long-period class BS obtained in step S36. Furthermore, the evaluation unit 103 may refer to a fragility curve (damage assessment graph) for each damage status, which shows the probability of damage occurrence according to the long-period ground motion class and the building's long-period class as a function, to predict the occurrence of damage whose probability of occurrence corresponding to the long-period ground motion class LS and the building's long-period class BS obtained in step S36 exceeds a predetermined value. Similarly, in step S39, damage assessment may be performed based on the long-period ground motion class LS, the building's long-period class BS, and the damage assessment table or damage assessment graph to identify evacuation locations.

[0080] 3. Earthquake information notification example 10 to 13 show examples of earthquake information delivered to terminal 20 (examples of text displayed on the display of terminal 20 or on an electronic bulletin board, and example broadcast text). Fig. 10 is a diagram showing an example of earthquake information displayed on terminal 20 of a salesperson at a commercial facility (department store) where the predicted measured seismic intensity warning is 5.3. In this example, an emergency earthquake warning has been issued, and it has been notified that the predicted seismic intensity is 5+, the arrival time is 10:30:29, and the time to spare is 16 seconds. Furthermore, evacuation instructions (to move to a nearby open space) are issued according to the time to spare and damage assessment (the building is safe, and exhibits will move).

[0081] 11 is a diagram showing an example of earthquake information displayed on the terminal 20 of a salesperson at a commercial facility (department store) where the predicted alarm instrumental seismic intensity MI is 5.3 and the long-period ground motion scale LS is 3. In this example, an emergency earthquake warning has been issued, and it has been notified that the predicted seismic intensity is upper 5, there will also be long-period ground motion, the arrival time will be 10:30:29, and the margin of time is 36 seconds, and furthermore, evacuation instructions (to move to sections B-2 and C-2 on the floor) have been issued according to the margin of time and damage assessment (the building is safe, but the showcases will collapse).

[0082] Figure 12 shows the earthquake at a school where the predicted warning instrumental seismic intensity MI is 5.3 and the margin time is 20 seconds. This is a diagram showing an example of earthquake information broadcast on the school's broadcasting room (displayed on a terminal in the school's broadcasting room). In this example, a notice is issued that an earthquake is occurring, and evacuation instructions are given to students in the gymnasium (to move to a corner) according to the time to evacuate, and to students in classrooms and hallways (to move away from glass windows and under desks) according to the time to evacuate.

[0083] Fig. 13 is a diagram showing an example of earthquake information displayed on an electronic bulletin board at a factory where the predicted alarm instrumental seismic intensity MI is 5.3 and the long-period ground motion scale LS is 3. In this example, the message is displayed indicating that there is XX seconds left until the earthquake motion arrives, and that the shaking will continue. Response instructions (stop machines, put out fires) and evacuation instructions (move away from windows and fixtures) are given according to the time left and damage assessment (the building is safe, and unfixed objects will move) and the damage assessment.

[0084] According to the earthquake information distribution system of this embodiment, when an Earthquake Early Warning is issued, the system predicts the measured seismic intensity (MI) and arrival time, as well as the maximum ground acceleration (PGA) or maximum ground velocity (PGV) and the building's response spectrum (FipSv), and performs damage assessment. The system then distributes information on evacuation instructions based on the damage assessment as earthquake information to terminals 20 located in locations where the measured seismic intensity (MI) exceeds a threshold. This allows evacuation that takes into account the impact of building damage, further improving safety. After an earthquake, the system calculates the building's response spectrum using a response calculation model based on observed seismic wave data and performs a damage assessment again. This allows the accuracy of the response spectrum prediction and the damage assessment to be confirmed, and information useful for business continuity planning (BCP) can be obtained. Furthermore, the system determines whether the building's natural period has changed based on the observed data. If the natural period has changed, the system re-establishes the building's rigidity and updates the response calculation model, thereby improving the accuracy of damage assessment.

[0085] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, terms cited in the specification or drawings as broadly defined or synonymous terms can be replaced with broadly defined or synonymous terms in other descriptions in the specification or drawings. [Explanation of symbols]

[0086] 1... Earthquake information distribution system, 2... Distribution company, 3... Dedicated line, 4... Network, 10... Server, 20... Terminal, 100... Processing unit, 101... Receiving unit, 102... Prediction unit, 103... Evaluation unit, 104... Distribution unit, 110... Communication unit, 120... Storage unit

Claims

1. a receiving unit for receiving emergency earthquake alerts distributed by the Japan Meteorological Agency; a prediction unit that calculates a predicted value of seismic intensity at a predetermined location based on the earthquake early warning when the earthquake early warning is received; an evaluation unit that predicts a response spectrum of a building at the predetermined location based on the earthquake early warning and performs damage evaluation of the building based on the predicted response spectrum; a distribution unit that distributes earthquake information including information regarding evacuation instructions based on the damage assessment to a terminal that is located at a predetermined location where the predicted value of the seismic intensity has exceeded a threshold value, The evaluation unit An earthquake information distribution system characterized by calculating the response spectrum of the building using a response calculation model based on the observation results of a seismometer installed in the building, and re-evaluating the damage to the building based on the calculation results of the response spectrum.

2. In claim 1, The evaluation unit An earthquake information distribution system characterized by predicting the response spectrum of the ground surface at the specified location based on the emergency earthquake warning, predicting the response spectrum of each floor of the building based on the predicted result of the ground surface response spectrum and a transfer function from the ground surface to each floor of the building, and performing a damage assessment of the building based on the predicted result of the response spectrum of each floor.

3. In claim 1, The evaluation unit An earthquake information distribution system characterized by predicting the maximum ground acceleration or maximum ground velocity at the specified location and the response spectrum of the building based on the emergency earthquake warning, and evaluating damage to the building based on the predicted results of the maximum ground acceleration or maximum ground velocity and the predicted results of the response spectrum.

4. In claim 1, The evaluation unit An earthquake information distribution system characterized by resetting the rigidity of the building based on the observation results of a first seismometer installed in the foundation of the building and a second seismometer installed on the roof of the building, and updating the response calculation model.

5. In claim 4, The evaluation unit An earthquake information distribution system characterized by determining whether the natural period of the building has changed based on the observation results of the first seismograph and the second seismograph, and resetting the rigidity if the natural period has changed.

6. In claim 1, The prediction unit When the Earthquake Early Warning is received, a predicted value of long-period ground motion having a period corresponding to the natural period of the building at the predetermined location is calculated based on the Earthquake Early Warning; The distribution unit An earthquake information distribution system characterized by distributing the earthquake information to terminals located in specified locations where the seismic intensity or the predicted value of the long-period ground motion exceeds a threshold.

7. a receiving step of receiving an emergency earthquake alert distributed by the Japan Meteorological Agency; When the emergency earthquake warning is received, the seismic intensity of a predetermined location is calculated based on the emergency earthquake warning. a prediction step of calculating a predicted value of an evaluation step of predicting a response spectrum of a building at the predetermined location based on the earthquake early warning and performing a damage assessment of the building based on the predicted response spectrum; a distribution step of distributing earthquake information including information on evacuation instructions based on the damage assessment to a terminal located at a predetermined location where the predicted value of the seismic intensity has exceeded a threshold value; In the evaluation step, An earthquake information distribution method characterized by calculating the response spectrum of the building using a response calculation model based on the observation results of a seismometer installed in the building, and re-evaluating the damage to the building based on the calculation results of the response spectrum.

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