JP5372879B2 - Earthquake disaster prevention system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To early and reliably detect earthquake motion really dangerous for a building. <P>SOLUTION: An earthquake disaster prevention system receives emergency earthquake alert information containing at least information of an earthquake location and its scale (magnitude) delivered when an earthquake occurs, and determines a risk of the building. The system includes a reception terminal 4 for receiving the emergency earthquake alert information and a vibration meter 2 disposed in the building for measuring at least one of acceleration, displacement and earthquake intensity generated by the earthquake as vibration, and determines generation of long-period ground motion for the building based on the earthquake location and magnitude included in the emergency earthquake alert information, and whether a long-period component containing a natural vibration period of the building is extracted from the signal measured by the vibration meter 2. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an earthquake disaster prevention system that prevents damage caused by long-period ground motion (surface waves with a period of several seconds to tens of seconds) due to a trench-type earthquake that is a plate boundary earthquake, and in particular, when a long-period ground motion occurs, the elevator can be safely Suitable for stopping.

  In recent years, damage to skyscrapers, long bridges, oil tanks, etc. is minimized by huge plate boundary earthquakes that cause long-period ground motions to areas far away from the epicenter of inland earthquakes that occur in inland active faults. The need for countermeasures is required.

  In particular, in elevators, it is known to predict the maximum acceleration due to seismic waves according to the position of a building based on an emergency earthquake bulletin delivered when an earthquake occurs, and to control a car, for example, described in Patent Document 1 Yes.

  In addition, in order to evaluate the seismic intensity at an assumed position with higher accuracy based on earthquake information, it is known to make a prediction by a distance attenuation formula from the position and magnitude of the earthquake, and is described in Patent Document 2, for example. .

  In addition, in order to accurately detect vibrations in long objects such as main ropes caused by long-period ground motion or strong winds, a vibration detector is installed at the top of the building, and the main rope's vibration response is predicted and calculated based on the signals. Is known, and is described, for example, in Patent Document 3.

JP 2007-161378 A JP 2007-71707 A JP 2007-331901 A

  Inland earthquakes, which are normal earthquakes, almost all periodic components attenuate with the passage of time after the arrival of the main motion, whereas in trench-type earthquakes, the ground resonates due to long periodic components, and several long-period earthquake motions occur. Lasts for minutes. Also, tremors caused by trench-type giant earthquakes cause broadband strong ground motions with short and long periods in the vicinity of the epicenter, and are transmitted to areas far away from the epicenter with little attenuation, and are large in sedimentary basin areas of large cities. It has the property of being amplified.

  Therefore, just as in the above prior art, the maximum acceleration due to the seismic wave is predicted, the seismic intensity is predicted by the distance attenuation formula from the epicenter position and magnitude, or the long period ground motion is detected by the vibration sensor. It is difficult to clearly distinguish a normal earthquake (inland earthquake) from a plate boundary earthquake by itself. In other words, since all periodic components increase in earthquakes that occur relatively close to the location of the building, even earthquakes that are normal and less dangerous are judged to be long-period ground motions. For long-period ground motion generated in, it is difficult to judge that it is long-period ground motion because it is small at the initial stage, and it cannot be judged unless it is already in a dangerous state after being greatly amplified. Judgment that there is is late.

  Normally, an elevator is equipped with an earthquake detector to stop safely in the event of an earthquake, but if the set value is lowered to detect long-period ground motion, it will malfunction due to small earthquakes or artificial vibrations that are less dangerous. Occur frequently and serviceability is lowered, which is not practical.

  An object of the present invention is to solve the above-described problems of the prior art, and to detect earthquake motion that is truly dangerous for the operation of buildings and elevators at an early stage and to prevent damage. Another purpose is to make the correspondence between danger and seismic motion detection more consistent, and to determine the occurrence of long-period seismic motion as early as possible, especially in the case of elevators, in terms of safety and serviceability. The goal is to achieve both.

In order to achieve the above object, the present invention provides an earthquake disaster prevention system that receives an emergency earthquake bulletin including information on at least an epicenter location and a magnitude (magnitude) distributed when an earthquake occurs, and determines the risk of a building. A receiving terminal for receiving the earthquake early warning, and a vibration meter installed in the building and measuring at least one of acceleration, displacement, and seismic intensity generated by the earthquake as vibrations, The magnitude and whether the long-period component including the natural vibration period of the building has been extracted from the signal measured by the vibrometer, and extracted by determining the occurrence of long-period ground motion for the building If the magnitude of the long-period component is larger than the comparison reference value, it is determined that the building is a long-period ground motion that is dangerous to the building, and the comparison reference value is the distance to the source position. But it is intended to decrease with decreasing and large.

According to the present invention, when the position and magnitude of the epicenter and the magnitude of the long period component including the natural vibration period of the building are larger than the comparison reference value, it is determined that the building is a dangerous long period ground motion, and the comparison reference value As the distance up to becomes larger, the elevator can be safely stopped by identifying a truly dangerous long-period ground motion at an early stage. Therefore, the safety of the elevator can be improved at a stage before the danger due to the resonance vibration of the building is increased without impairing the serviceability.

The figure which shows the structure of the earthquake disaster prevention apparatus of the elevator by one embodiment of this invention. The figure which shows the acceleration waveform of an earthquake, and the waveform of a long period component. The figure which shows typically the relationship between the distance to the epicenter of a general earthquake, and the magnitude | size of a long period component. The figure which shows the detailed structure of the long-period vibration component extraction means of one Embodiment. The figure which shows the detailed structure of the comparison reference value calculation means of one Embodiment. The figure which shows the flow of operation | movement of the comparison means and control operation control means of one Embodiment. The figure which shows the timing when control operation control is started by the earthquake disaster prevention apparatus of an elevator. The figure explaining the motion of the earthquake disaster prevention apparatus which uses the signal of the vibration measurement means in one embodiment as a trigger.

  FIG. 1 shows an elevator earthquake disaster prevention system. A vibration meter (vibration measuring means) 2 is installed on the lowest floor of a building where the elevator 1 is installed, and measures earthquake vibration. Specifically, an acceleration sensor or a seismometer is desirable. Further, the long-period vibration component extraction unit 3 extracts a long-cycle (several seconds to several tens of seconds) vibration component from the signal measured by the vibration measurement unit 2.

  The earthquake information obtaining means 4 is a means for obtaining information about an earthquake that has occurred, and is a receiving terminal that immediately receives information delivered immediately after the occurrence of an earthquake, such as an emergency earthquake warning, such as an Internet line, satellite communication, terrestrial digital broadcasting , A receiving terminal using various communication media such as cable lines for cable television. The received earthquake information includes latitude, longitude, depth representing the location of the earthquake, magnitude representing the magnitude of the earthquake, and time of occurrence of the earthquake.

  The long-period vibration component comparison reference value calculation means 5 calculates a comparison reference value (long-period vibration component) for determining whether or not the generated earthquake is a long-period ground motion.

  The comparison means 6 compares the comparison reference value with the magnitude of the long-period vibration component extracted by the long-period vibration component extraction means 3. The control operation control means 7 controls the control operation of the elevator 1 based on the comparison result. The long-period vibration component extraction means 3, the long-period vibration component comparison reference value calculation means 5, and the comparison means 6 are configured as a program on a microprocessor provided in the control panel of the elevator together with the control operation control means 7. Is good.

  Next, determination of long-period ground motion will be described with reference to FIGS.

  100 and 102 in FIG. 2 are acceleration waveforms of earthquakes occurring at the same distance from the observation point, 100 is a general earthquake, and 102 is an earthquake with long-period ground motion. Reference numerals 101 and 103 denote waveforms obtained by extracting long-period components from the acceleration waveforms of the respective earthquakes by filtering processing. As shown in the figure, when long-period ground motion is occurring, long-period vibration is amplified over time due to the resonance phenomenon of the ground. This amplification effect can be recognized even in a relatively early stage of the earthquake, and comparing the portions 104 and 105 in the figure, when the long-period ground motion is occurring, the long-period component is larger in 105. Yes.

  A curve 106 in the graph shown in FIG. 3 is a graph schematically showing the relationship between the distance from the observation point to the epicenter in a general earthquake and the magnitude of the long-period component in the initial stage of the earthquake. The long-period component in a general earthquake is a small value at point A far from (distant from) the epicenter compared to 107 when long-period ground motion occurs, but is the same at point B near the epicenter. It becomes size. However, since long-period components in general earthquakes do not involve ground resonance, they decay with time and do not involve dangers such as long-period ground motion. Therefore, it is difficult to determine the risk of long-period ground motion based only on the magnitude of the long-period component in the initial stage of the earthquake.

  On the other hand, if the distance to the epicenter is known, the magnitude of the long-period component at the initial stage in a general earthquake can be roughly predicted as shown by the curve 106 in FIG.

  And if a long period component larger than the magnitude of the long period component predicted in the case of a general earthquake is observed, it is determined that a long period ground motion is occurring. That is, even in the case of the point B in FIG. 3, if the observed long-period component has a larger value of 108 than the case of a general earthquake, it is determined as a long-period ground motion; I decided to judge. Accordingly, it is possible to accurately determine the occurrence of long-period ground motion by lowering the determination reference value according to the distance to the epicenter, and if the distance becomes large, the determination reference value is lowered.

  Next, details and operations of the earthquake disaster prevention device for an elevator will be described with reference to FIGS. 4, 5, and 6.

  FIG. 4 shows a detailed configuration example of the long-period vibration component extraction means 3. Reference numeral 10 denotes a parameter related to the vibration characteristics of the building, which is information such as the natural vibration period of the building or the height of the building that can be specified. Reference numeral 11 denotes filter means for extracting a periodic component including the natural vibration period of the building from the earthquake vibration signal (acceleration, velocity) obtained by the vibration measuring means 2. That is, a bandpass filter centered on the natural vibration period of the building or a low-pass filter that passes a long-period component including the natural vibration period is preferable.

  FIG. 5 shows a detailed configuration example of the comparison reference value calculation means 5 of the long-period vibration component. Reference numeral 20 denotes an epicenter distance calculating means for calculating the latitude, longitude and depth of the epicenter position obtained by the earthquake information obtaining means 4 and the latitude and longitude of the location of the building to the distance from the epicenter. 21 is a means for calculating the magnitude of the long-period component. From the distance to the epicenter calculated in 20 and the magnitude of the earthquake obtained by the earthquake information obtaining means 4, the magnitude of the long-period component in a general earthquake is calculated. calculate. Specifically, for example, it is calculated by the following calculation formula.

  Here, L is the distance to the epicenter, M is the magnitude of the earthquake, a and b are parameters determined by the calculated periodic component, and A is the magnitude of the periodic component. a and b may select parameters corresponding to the natural vibration period of the building. Note that various calculation methods can be considered for the parameters a and b. For example, the parameters a and b may be statistically calculated from data relating to the epicenter distance and the magnitude of each periodic component in various general earthquakes.

  The comparison reference value setting means 22 adds a margin in anticipation of a prediction error based on the calculation formula (Equation 1) to the magnitude of the long-period component calculated in 21 as an offset and sets it as a comparison reference value. In addition, even if the epicenter is very far away and long-period ground motion is occurring, if the vibration is very small and there is no danger, it is not necessary to determine long-period ground motion. When the comparison reference value is equal to or less than a predetermined value, the reference value may be set by correcting upward to a predetermined value.

  FIG. 6 shows details of the operations of the comparison means 6 and the control operation control means 7. A series of operations shown in FIG. 6 is executed when the earthquake information obtaining unit 4 receives information about a newly generated earthquake. First, the comparison means 6 compares the vibration component extracted by the long-period vibration component extraction means 3 with the comparison reference value calculated by the comparison reference value calculation means 5 of the long-period vibration component, and the long-period vibration component is compared with the comparison reference value. When it becomes larger, a command to start control control is issued to the control operation control means 7 (S1).

  When the control operation control means 7 receives an instruction to start control control, the control operation control means 7 calculates a grace time from the information on the location of the epicenter and the earthquake occurrence time obtained by the earthquake information obtaining means 4 (S2). This grace time is the expected time until the ropes of the elevator reach a dangerous vibration level due to the resonance phenomenon of the building due to long-period ground motion, and is calculated according to the following procedure.

  The average time from the occurrence of long-period ground motion until the ropes reach a dangerous vibration level is obtained in advance by simulation or the like. When long-period ground motion actually occurs, the elapsed time Te after the main motion of the earthquake reaches the building is calculated by the following formula.

  Here, To is the earthquake occurrence time, Tc is the current time, Vs is the propagation speed of the main motion (S wave) of the earthquake, and L is the distance to the epicenter. Then, the grace time is calculated by subtracting the elapsed time Te from the average time until the dangerous vibration level is reached.

  Next, when the grace time is shorter than the time T1 required to stop the elevator at the nearest floor at the current car position, the elevator is immediately stopped (S3, S4). When the grace time is longer than T1 and shorter than the time T2 required to stop at the current floor at the current car position, the vehicle is stopped at the nearest floor (S5, S6). If the grace time is longer than T2, the safety floor is stopped.

  The safety floor is the position of the car that can minimize the damage to the elevator when the building shakes greatly due to a long-period earthquake. For example, the rope length does not match the natural vibration period of the building and the natural vibration period of the ropes. The car position should be selected.

  FIG. 7 is a diagram illustrating a timing at which control operation control is started by the elevator earthquake disaster prevention apparatus. Control control is started at a point 113 when the long-period component 110 of the ground motion exceeds the comparison reference value 112 set according to the distance to the epicenter. In contrast, the vibration 111 of the ropes gradually increases in amplitude due to resonance with the long-period component, and exceeds the danger amplitude 114 at 115. Therefore, when the elevator is stopped by detecting or predicting the vibration of the ropes, the control control is started at 115.

  However, in the example described with reference to FIG. 2, since the control control can be started at an earlier stage by the time indicated by 116 in FIG. 7, the elevator can be stopped more safely.

In the above example, the determination of long-period ground motion is performed using the reception of earthquake information as a trigger. As shown in FIG. 8, the trigger is that the vibration measured by the vibration measuring means 2 exceeds a predetermined value. Long-period ground motion determination processing may be performed.
The earthquake information obtaining means 4 is provided with a means for storing earthquake information, and the latest received earthquake information is always stored. When the vibration (acceleration) measured by the vibration measuring means 2 exceeds the set value, the earthquake information stored in the earthquake information obtaining means is examined, and the stored earthquake information is generated within a predetermined time from the current time. If it is, long-period ground motion determination processing is performed by comparing the comparison reference value and the long-period vibration component using the earthquake information (S10, S11, S12). And as a result of the comparison with a comparison reference value and a long period vibration component, when it determines with a long period earthquake, control operation control is started (S13, S14). If there is no earthquake occurring within the predetermined time, or if it is not determined as a long-period earthquake, normal operation is continued (S15).

  As the set value in S10, for example, a very low set value that can be detected even in an earthquake that occurred in a distant place is used. In addition, the predetermined time in S11 is a value that includes the time until an earthquake that has occurred far away reaches the building.

  The control operation control means 7 may immediately stop the elevator at the nearest floor at the stage when the control control start command is issued from the comparison means 6 regardless of the delay time.

  Further, the long-period vibration component extraction means 3 obtains a velocity signal by integrating the acceleration signal measured by the vibration measurement means 2, and the long-period vibration component comparison reference value calculation means 5 is a vibration velocity in a general earthquake. The comparison reference value may be calculated. These may further obtain a displacement signal and calculate a comparison reference value for vibration displacement. This is due to the fact that long-period earthquake vibrations appear greatly in speed and displacement and are therefore easy to detect.

  If another earthquake occurs during the comparison of the comparison reference value and the long-period vibration component, and the earthquake information is received, the comparison reference value calculated from the earthquake information is greater than the current comparison reference value. The comparison reference value is changed only when it becomes smaller, otherwise the current comparison reference value is maintained. Thereby, even when a general earthquake occurs nearby, long-period ground motion due to a distant earthquake can be detected correctly.

  The vibration measuring means 2 may be installed on the middle floor or the top floor of the building. In this case, the comparison reference value calculated by the comparison reference value calculation means 5 is calculated by taking into account the amplification effect of the vibration caused by the building.

1 Elevator 2 Vibrometer (Vibration measurement means)
3 Long-period vibration component extraction means 4 Receiving terminal (earthquake information acquisition means)
5 Comparison reference value calculation means 6 Comparison means 7 Control operation control means

Claims (3)

In the earthquake disaster prevention system that receives emergency earthquake bulletin information including at least the epicenter location and magnitude (magnitude) information delivered at the time of the earthquake occurrence, and determines the danger of the building,
A receiving terminal for receiving the earthquake early warning;
A vibration meter installed in the building and measuring at least one of acceleration, displacement, and seismic intensity generated by an earthquake as vibration;
A long period with respect to the building according to whether or not a long period component including a natural vibration period of the building is extracted from a signal measured by the vibrometer, and a location and magnitude of the earthquake early warning If the magnitude of the long-period component extracted by judging the occurrence of seismic motion is larger than the comparison reference value, it is determined that the building is dangerous long-period ground motion, and the comparison reference value has a large distance to the epicenter. An earthquake disaster prevention system characterized by being made small .   2. The earthquake disaster prevention system according to claim 1, wherein the comparison reference value is determined on the basis of the magnitude of a long-period component in a general earthquake.   The earthquake disaster prevention system according to claim 1, wherein an elevator is installed in the building and the elevator is stopped when it is determined that long-period ground motion has occurred.

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