JP2003176900A - Presuming method for earthquake damage generation and presuming device for earthquake damage generation - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a presuming method for earthquake damage generation and a presuming device for earthquake damage generation capable of specifically presuming an existence of a generation of a damage of pipes in a piping network of city gas, city water or the like even if an earthquake of any scale is generated and a generation position of the damage in the case where the damage is generated at a high accuracy. <P>SOLUTION: The piping network provided at a predetermined area is divided to a plurality of segments. Data regarding a natural vibration of the ground; data regarding rupture strength of the pipes; and data regarding a size of a motion of the earthquake observed when the earthquake is generated at the predetermined area or a size of an external force imparted by the earthquake are memorized in a critical value memory part 100 every at the respective segments. A damage generation presuming part 200 presumes an existence of a generation of a damage of the pipes caused by the earthquake based on the data. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an earthquake damage occurrence estimating method and an earthquake damage occurrence estimating apparatus.

[0002]

BACKGROUND OF THE INVENTION City gas and water and sewer pipe networks are generally
In order to reliably supply public resources such as fuel gas and tap water for general households to consumers in a given area, within the area to be supplied, as if it were a vascular network in the human body. It is installed in a complex network. For example, in a city gas piping network, so-called conduits are almost entirely buried underground in a predetermined area under the jurisdiction of a gas supplier, and are generally called buried pipes. However, there are some areas where the conduits are exposed to the ground, although the number is small.

In such a piping network (in other words, a network of buried pipes), when an earthquake occurs, the piping may be damaged depending on the scale of the earthquake, so that safety can be ensured. , It is necessary to accurately grasp the damage situation that occurred in the piping due to the earthquake at that time.

Therefore, in the prior art, the "damage rate" of the pipe caused by the earthquake is statistically calculated based on the information obtained so far regarding the damage situation of the pipe when the earthquake occurred in the past. I was trying to ask.

For example, when the so-called Kobe Earthquake occurred, the situation of damage occurring to the piping network in the Kobe Hanshin area was investigated from the viewpoint of the material of the piping and the type of valve, and the information was statistically processed. Then, the probability of damage occurring to the piping network in the event of an earthquake of the Kobe Great Earthquake is set in advance. Then, when an earthquake of similar magnitude occurs, the damage rate of the pipe caused by the earthquake is calculated based on the predetermined damage occurrence probability. Alternatively, the probability of damage to the piping network in multiple other past earthquakes is investigated, and the correlation between the scale of the earthquake and the damage rate to the piping network is obtained statistically from those data, and the actual earthquake occurs. In doing so, the damage rate of the piping network corresponding to the magnitude of the earthquake that occurred at that time is calculated based on the correlation obtained in advance.

As described above, according to the conventional technique, when an earthquake occurs, the occurrence status of the damage to the pipe caused by the earthquake is preliminarily determined based on the earthquakes reported in the past and the information on the damages caused by the earthquakes. From the statistical data we had obtained, we were probabilistically (or statistically) inferred in the form of a “disaster rate”.

[0007]

However, according to the conventional technique as described above, the damage situation of the pipe when the earthquake occurs, for example, "the damage probability of the pipe buried in 1970 in Awaji district is 50%. It can only be estimated stochastically. For this reason, it is difficult to clearly understand whether or not the pipe has been damaged due to the earthquake that has occurred.

More specifically, when an earthquake actually occurs, the pipe is either damaged or undamaged. For example, "the damage probability of the pipe is 50%".
According to such an estimation, it is actually unknown whether or not the pipe is damaged. As described above, in the conventional technique, it is not possible to clearly (binarily) grasp the presence or absence of breakage, so it is difficult to surely and swiftly take measures for ensuring safety. In addition, it is not possible to accurately grasp which position in the piping network is damaged due to the earthquake.

Further, in the conventional technique, the probability of pipe damage is calculated by statistically processing data relating to damage to pipes caused by earthquakes (past earthquakes) that occurred in the past, and the magnitude of the past earthquakes Regarding the damage to the piping at this time, not enough data has been grasped to cover all cases, and the reliability (accuracy or certainty) of the damage probability obtained is not always sufficient. In addition, since it has only recently begun in earnest to collect information on damage to pipes in the event of an earthquake as a countermeasure against earthquakes, the amount of collected information (cases) on damage to pipes is not always sufficient. The reality is that it cannot be said to be a thing. Therefore, in the conventional technique, the accuracy of the probability of pipe damage estimated when an earthquake actually occurs is not necessarily high.

For example, in recent years, information about damage to pipes in the Kobe earthquake has been obtained. Therefore, when an earthquake of the same magnitude as this Kobe earthquake occurs, the probability of pipe damage can be calculated with relatively high accuracy. It is considered possible. However, future earthquakes are not necessarily of the same scale or smaller than the Kobe earthquake, so they are larger than the Kobe earthquake (unprecedented).
In the event of an earthquake, it is difficult to obtain a substantially accurate damage probability.

In addition, in order to supplement the disadvantage of the above-described method of estimating the damage probability of piping by the conventional statistical method, each important point in the piping network is actually dug up when an earthquake occurs. And check the condition of the buried pipe at that position,
It is possible to perform so-called on-site inspection, but in reality, it was time consuming to take safety measures before digging back such a buried pipe after the earthquake occurred. Needless to say, it is often too late, and it is not suitable as a coping method for ensuring safety. Moreover, if an earthquake occurs,
In some cases, access such as traffic or communication by telephone is blocked, and even if an attempt is made to investigate the present condition of the damage caused by the earthquake, it is not possible to even reach the position of the buried pipe. For this reason, the technique of conducting a physical inspection of the condition of the buried pipe at each key point is often substantially useless when an earthquake occurs.

The present invention has been made in view of the above problems, and an object thereof is to provide a pipe network such as city gas or water supply when an earthquake occurs regardless of the magnitude of the earthquake. To provide an earthquake damage occurrence estimation method and an earthquake damage occurrence estimation device that can accurately and accurately estimate the presence or absence of piping damage and the location of the damage, if any. is there.

[0013]

The earthquake damage estimation method according to the present invention divides a pipe network provided in a predetermined area into a plurality of segments, and for each segment, data on natural vibration of the ground and a pipe Whether or not pipe damage has occurred due to an earthquake, based on the data on damage strength and the data on the magnitude of earthquake motion observed when an earthquake occurs in a specified area or the magnitude of external force applied by the earthquake Is estimated.

The earthquake damage estimating apparatus according to the present invention is
Dividing the piping network provided in a predetermined area into multiple segments, for each segment, data on the natural vibration of the ground, data on the damage strength of the piping, and when a earthquake occurs in the predetermined area are observed. A damage occurrence estimating means for estimating the occurrence of damage to the pipe due to the earthquake based on the magnitude of the earthquake motion or the data relating to the magnitude of the external force applied by the earthquake is provided.

That is, in the earthquake damage estimating method or the earthquake damage estimating apparatus according to the present invention, the piping is stochastically based on the conventional statistical data on the magnitude of the past earthquake and the damage to the piping caused by the earthquake. Data (T or L) on the natural vibration of the ground where pipes such as gas conduits are installed, rather than estimating the occurrence of damage
And data on the damage strength of the pipe (Dcr or S
Icr or Ucr or Fcr) and the magnitude of the ground motion observed (including indirect measurement) when an earthquake occurs in a predetermined area where the piping network is installed, or the magnitude of the external force given by the earthquake. Data on (SI or U
Or, based on F) and, the presence or absence of pipe damage due to the earthquake that occurred at that time is estimated. Moreover, at this time, the pipe network provided in the predetermined area is divided into a plurality of segments in advance and grasped, and it is estimated for each segment whether or not the pipe is damaged due to the earthquake.

More specifically, in the earthquake damage estimation method according to the present invention, the piping network provided in a predetermined area is divided into a plurality of segments, and the natural vibration period or the natural vibration wavelength of the ground and the piping are divided for each segment. The critical seismic motion value, which is the critical seismic motion value that causes pipe damage, is calculated based on the critical deformation amount that causes the damage of the pipe, and when the earthquake occurs, the seismic motion value and the critical seismic motion observed in the earthquake occur. By comparing with the value, it is estimated for each segment whether or not pipe damage due to the earthquake has occurred.

Further, the earthquake damage estimating apparatus according to the present invention is
The pipe network provided in a given area is divided into multiple segments, and for each segment, the pipe is determined based on the natural vibration period or natural vibration wavelength of the ground and the critical deformation amount that causes pipe damage. A critical value storage means that stores a critical seismic motion value that is a critical seismic motion value at which damage occurs, and when an earthquake occurs in a predetermined area, compares the seismic motion value observed in the earthquake with the critical seismic motion value, A damage occurrence estimating means is provided for estimating, for each segment, whether or not the pipe is damaged due to the earthquake.

That is, in the earthquake damage estimating method or the earthquake damage estimating apparatus according to the present invention, the natural vibration period (T) or the natural vibration wavelength of the ground is used as the data of the "swayability of the ground" for each segment in the piping network. (L)
Of the critical seismic motion value (SIc) using the data of
r) is calculated in advance, and when an earthquake occurs, the earthquake motion value (SI) of that earthquake is compared with the critical earthquake motion value (SIcr) to estimate whether the pipe of each segment is damaged or not. To do.

For example, if the earthquake motion value observed (including indirect measurement; the same applies below) when an earthquake occurs exceeds the critical seismic motion value of a certain segment, the piping of that segment It is presumed that damage occurred due to the earthquake at that time, and if the earthquake motion value was less than the critical earthquake motion value, it is estimated that no damage occurred. Alternatively, if the safety factor is estimated higher and the seismic motion value observed at the time of the earthquake is greater than or equal to the critical seismic motion value for a certain segment, the piping for that segment will contain the earthquake at that time. It is presumed that damage has occurred, and if the seismic motion value is less than the critical seismic motion value of that segment, it is assumed that the pipe of that segment was not damaged by the earthquake at that time. May be.

Alternatively, in the earthquake damage estimation method according to the present invention, the pipe network provided in a predetermined area is divided into a plurality of segments, and the natural vibration period or the natural vibration wavelength of the ground and damage to the pipe are broken for each segment. Based on the amount of critical deformation that occurs, the critical seismic amplitude value, which is the critical seismic amplitude that causes pipe breakage, is obtained, and when an earthquake occurs,
By comparing the seismic amplitude value observed in the earthquake with the critical seismic amplitude value, the presence or absence of pipe breakage caused by the earthquake is estimated for each segment.

Further, the earthquake damage estimating apparatus according to the present invention is
The pipe network provided in a given area is divided into multiple segments, and for each segment, the pipe is determined based on the natural vibration period or natural vibration wavelength of the ground and the critical deformation amount that causes pipe damage. Critical value storage means for storing a critical seismic amplitude value which is a critical seismic amplitude at which breakage occurs,
When an earthquake occurs in a specified area, the earthquake amplitude value observed in that earthquake is compared with the critical earthquake amplitude value to estimate the occurrence of pipe damage due to that earthquake for each segment Damage Occurrence estimation means.

That is, in the earthquake damage estimating method or the earthquake damage estimating apparatus according to the present invention, the data of the natural vibration period (T) or the natural vibration wavelength (L) of the ground and the breakage of the pipe are obtained for each segment in the piping network. The critical seismic amplitude value (Ucr) is obtained in advance by using the data of the critical deformation amount (Dcr) as the critical value at which the earthquake occurs, and when the earthquake occurs, the amplitude value (U) of the earthquake and the critical seismic amplitude value (Ucr) is compared to estimate whether or not the pipe of each segment is damaged.

Alternatively, in the earthquake damage estimation method according to the present invention, the pipe network provided in a predetermined area is divided into a plurality of segments, and the natural vibration period or the natural vibration wavelength of the ground and the damage to the pipe are broken for each segment. The critical seismic motion value, which is the critical seismic motion value that causes pipe breakage, is calculated based on the critical stress value that occurs, and when an earthquake occurs in a specified area, the seismic motion value and the critical seismic motion observed during the earthquake occur. By comparing with the value, it is estimated for each segment whether or not pipe damage due to the earthquake has occurred.

The earthquake damage estimating apparatus according to the present invention is
The pipe network provided in a predetermined area is divided into a plurality of segments, and for each segment, the pipe is determined based on the natural vibration period or natural vibration wavelength of the ground and the critical stress value that causes pipe damage. A critical value storage means that stores a critical seismic motion value that is a critical seismic motion value at which damage occurs, and when an earthquake occurs in a predetermined area, compares the seismic motion value observed in the earthquake with the critical seismic motion value, A damage occurrence estimating means is provided for estimating, for each segment, whether or not the pipe is damaged due to the earthquake.

That is, in the earthquake damage estimating method or the earthquake damage estimating apparatus according to the present invention, the data of the natural vibration period (T) or the natural vibration wavelength (L) of the ground and the damage of the pipe are broken for each segment in the piping network. Based on the critical stress value (Fcr) data as the critical value at which
The critical seismic motion value (SIcr) is obtained in advance, and when an earthquake occurs, the seismic motion value (SI) of the earthquake is compared with the critical seismic motion value (SIcr) to determine whether the pipe of each segment is damaged. Presume.

In the earthquake damage estimating method or the earthquake damage estimating apparatus according to the present invention as described above, a predetermined pipe network is provided on the earth or as described above based on a so-called geophysical point of view. A segment with a critical seismic intensity value or critical seismic amplitude value that is greater than the seismic intensity value or seismic amplitude value of the largest (potential) earthquake that can occur in a region is presumed to be "constantly unbroken" You may keep it.

By doing so, it is possible to omit the damage estimation when an earthquake actually occurs for a segment in which the pipe is not damaged no matter how large-scale earthquake occurs. In addition, at least that much time and effort of information processing is simplified.

Another seismic damage estimation method according to the present invention is to divide a piping network provided in a predetermined area into a plurality of segments, and for each of the segments, perform fluidization of the ground expected when an earthquake occurs. Estimate the presence or absence of pipe damage due to the earthquake that occurred, based on the data related to the pipe breakage strength in the flow direction and the data related to the flow volume observed or estimated when the earthquake occurred. ,
That is.

Further, another earthquake damage estimating apparatus according to the present invention divides a piping network provided in a predetermined area into a plurality of segments, and for each of the segments, the flow of ground that is expected when an earthquake occurs. Based on the data on the damage strength of the pipe in the flow direction due to the liquefaction and the data on the flow amount observed or estimated when the earthquake occurred, the existence of the damage to the pipe due to the earthquake occurred A damage occurrence estimating means for estimating is provided.

That is, in another earthquake damage estimating method or earthquake damage estimating apparatus according to the present invention, data concerning the damage strength of the pipe in the flow direction due to the fluidization of the ground assumed when an earthquake occurs (δcr or Ucr or Fcr)
And the data on the flow rate observed or estimated when the earthquake occurred (δ or U or F), the occurrence of pipe breakage due to the fluidization of the ground caused by the earthquake that occurred. Estimate the presence or absence of.

More specifically, another seismic damage estimation method according to the present invention is assumed when a pipe network provided in a predetermined area is divided into a plurality of segments and an earthquake occurs in each segment. The critical amount of deformation that causes pipe damage in the flow direction due to the fluidization of the ground is obtained, and when an earthquake occurs, the flow rate that is observed or assumed due to the fluidization of the ground due to the earthquake By comparing with the critical deformation amount, it is estimated for each segment whether the pipe is damaged due to the earthquake.

Further, another earthquake damage estimating apparatus according to the present invention divides a piping network provided in a predetermined area into a plurality of segments, and obtains each segment, and the ground assumed when an earthquake occurs is obtained. Critical value storage means that stores the critical deformation amount that causes pipe damage in the flow direction due to the fluidization of the ground, and when an earthquake occurs, it is observed or estimated due to the fluidization of the ground due to the earthquake A breakage occurrence estimating means for comparing the flow rate and the critical deformation quantity and estimating whether or not breakage of the pipe due to the earthquake has occurred is provided for each segment.

That is, in the other earthquake damage estimating method or earthquake damage estimating apparatus according to the present invention, the critical deformation amount causing pipe damage in the flow direction due to the fluidization of the ground assumed when an earthquake occurs ( δcr) and the flow rate (δ) that is observed or assumed due to the fluidization of the ground caused by the earthquake, and compares the occurrence of pipe damage due to the earthquake at that time. presume. Moreover, at this time, the pipe network provided in the predetermined area is divided into a plurality of segments, and the data is individually grasped for each segment, and the occurrence of the damage of the pipe due to the earthquake occurred for each segment. Estimate the presence or absence.

For example, if the flow rate (δ) observed or assumed by the earthquake that occurred exceeds the critical deformation rate (δcr) of the pipe, it is estimated that the pipe is damaged and the flow rate (δ If δ) is less than or equal to the critical deformation amount (δcr) of the pipe, it is estimated that the pipe has not been damaged.
Or, by estimating the safety factor higher, if the flow rate (δ) is greater than or equal to the critical deformation rate (δcr), it is estimated that the pipe is damaged, and the flow rate (δ) causes the critical deformation of the pipe. If it is less than the amount (δcr), it may be estimated that the pipe is not damaged.

Alternatively, another seismic damage estimation method according to the present invention divides a piping network provided in a predetermined area into a plurality of segments, and for each of the segments, the flow of ground that is expected when an earthquake occurs. Determining the amount of critical deformation that causes pipe breakage in the flow direction due to seismicity, and when an earthquake occurs in a predetermined area, based on the seismic motion value or earthquake amplitude value observed in that earthquake, the ground caused by the earthquake The amount of flow caused by the fluidization is estimated, the amount of flow is compared with the amount of critical deformation, and the presence or absence of breakage of the pipe due to the earthquake at that time is estimated for each segment.

Further, another earthquake damage estimating apparatus according to the present invention divides a piping network provided in a predetermined area into a plurality of segments, and obtains each segment, and the ground assumed when an earthquake occurs is obtained. Critical value storage means for storing the critical deformation amount that causes pipe damage in the flow direction due to fluidization of, and when an earthquake occurs, based on the seismic motion value or the earthquake amplitude value observed in the earthquake, Estimate the flow amount caused by the fluidization of the ground due to the earthquake at that time, compare the flow amount with the critical deformation amount, and estimate the occurrence of pipe damage due to the earthquake for each segment Damage Occurrence estimation means.

That is, in another earthquake damage estimating method or earthquake damage estimating apparatus according to the present invention, the critical deformation amount (amount of deformation that causes pipe damage in the flow direction due to fluidization of the ground assumed when an earthquake occurs) δcr), and when an earthquake occurs, the seismic motion value (SI) observed at that earthquake
Or, based on the seismic amplitude value (U), the flow rate (δ) caused by the fluidization of the ground caused by the earthquake is estimated, and the flow rate (δ) and the critical deformation amount of the pipe ( By comparing with δcr), it is estimated whether pipe damage will occur due to the earthquake at that time.

In another seismic damage estimating method or seismic damage estimating device according to the present invention, a segment having a pipe within a predetermined distance from a seawall that is substantially affected by the fluidization of the ground among the pipes of the piping network. Only with respect to the above, it may be possible to estimate whether or not the pipe is broken due to the fluidization of the ground.

That is, within a predetermined distance from the revetment (for example, within a distance of 100 meters from the revetment), the flow amount of the ground (δ that occurs due to the fluidization of the ground compared to the location of other terrain). The present inventors have confirmed that) is particularly large. Therefore, pay particular attention to locations where such ground fluidization is likely to occur as points of caution where pipe damage due to ground fluidization is likely to occur, and attach particular importance to segments that meet such conditions. By estimating the presence or absence of pipe breakage due to ground fluidization, for other segments where the probability of ground fluidization is low, whether there is damage due to ground fluidization May be omitted.

By doing so, it is possible to omit the estimation of damage due to the fluidization of the ground when an earthquake actually occurs in the segment in which the probability of the ground fluidization occurring is low. At least that amount of information processing is simplified.

As the flow rate (δ) due to the fluidization of the ground, the flow rate in the direction orthogonal to the revetment is estimated, and the critical deformation amount (δcr) that causes pipe damage is orthogonal to the revetment. You may take it in the direction.

That is, the flow amount of the ground (horizontal deformation amount due to the fluidization of the ground) generated within a predetermined distance from the revetment as described above is almost always in the direction orthogonal to the quay wall of the revetment. Since it occurs most noticeably, the flow rate (δ) of the ground in the direction orthogonal to such a revetment and the critical deformation amount (δcr) of the pipe in the same direction are compared to determine the fluidization of the ground. It is desirable to estimate the occurrence of damage due to this.

Here, in the above earthquake damage estimating method or earthquake damage estimating apparatus, the pipe network is discretized into individual segments in accordance with a predetermined classification method focusing on the connection form of the pipes and grasped, It is also desirable to estimate for each segment whether or not pipe damage due to an earthquake has occurred.

More specifically, as such a classification method, based on structural mechanical and topological points of view, the connection form of the pipes is a straight line type having a predetermined length or more, a curved pipe type having a bend, or a midway point. T-shaped with at least 3 branches, at least 3
It is effective to classify the pipe network into individual segments based on this classification method. However, it goes without saying that it is not limited to such a classification method. In addition to this, for example, it is also possible to classify into four types of a straight portion, a curved pipe portion, a T-shaped branch portion, and an H-shaped branch portion. Alternatively, in more detail, in addition to the above classification, a classification method including the presence or absence of a valve is also possible.

Further, in the above earthquake damage estimating apparatus, the critical value storage means associates, for each segment, the data on the geographical position of the segment within the predetermined area with the data on the critical seismic intensity value on the segment. When the earthquake occurs, the damage occurrence estimation means compares the earthquake motion value observed in the earthquake with the critical seismic motion value to determine the location of the damage to the pipe caused by the earthquake. It may be possible to estimate whether the segment has occurred.

Further, in the other earthquake damage estimating device described above,
The critical value storage means stores, for each segment, data relating to the geographical position of the segment and a critical deformation amount causing pipe damage in the flow direction due to fluidization of the ground in association with each other in advance. When the earthquake occurs, the failure occurrence estimating means compares the flow rate observed or estimated in the earthquake with the critical deformation quantity, and at which position the segment of the pipe that was damaged due to the earthquake occurred. Alternatively, it may be estimated.

Further, a map of a pipe network in a predetermined area is displayed on the screen, and a damage occurrence position display means for displaying the damage occurrence position estimated by the damage occurrence estimation means on the map may be provided. Good. By doing this, when an earthquake actually occurs, the location of the estimated pipe damage is automatically displayed on the map of the piping network in the specified area, and By doing so, it is possible to present to the user the broken points that have occurred in the piping network at a glance.

The earthquake damage estimating method and the earthquake damage estimating apparatus according to the present invention can be applied to the city gas piping network and the water supply / sewerage piping network as the above piping network.
Needless to say, it can be applied to various piping networks.

Here, symbols such as SI, δ and U shown in parentheses in the description of the above-mentioned solution means the seismic motion value, the ground flow rate, the seismic amplitude value, etc., respectively. The clear definition and specific contents of the physical quantity are described in detail in the embodiments described below.

[0050]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a schematic configuration of an earthquake damage estimating apparatus according to an embodiment of the present invention. The earthquake damage estimation method according to the embodiment of the present invention is embodied by the operation or action of this earthquake damage estimation device, and therefore will be described below together.

This earthquake damage estimation device estimates the damage situation of pipes (presence or absence of pipe damage and its position) when an earthquake occurs in the region for the city gas pipe network provided in a predetermined region. The main parts of the critical value storage unit (critical value storage means) 100, the damage occurrence estimation unit (damage occurrence estimation means) 200, and the damage occurrence position display unit (damage occurrence position display means) 300 are as follows. It is configured.

The critical value storage unit 100 divides a piping network, which is stretched in a mesh in a predetermined area such as almost the entire Kanto area, into a mesh of a predetermined size, and divides it into a plurality of segments. As it is grasped, an identification number (N = 1, 2, 3 ...) Is attached to each segment, and the natural vibration period (T) or the natural vibration wavelength (L) of the ground and the pipe are damaged. The critical seismic motion value (SIc), which is a critical seismic motion value at which breakage occurs in the pipe in the segment, which is obtained in advance based on the critical deformation amount (Dcr).
r), the flow critical deformation (δcr) data that presumes that pipe damage will occur in the flow direction due to the fluidization of the ground when an earthquake occurs, and that segment Data ((x, y); for example, Cartesian coordinate data) about the position on the map is stored in association with each other. The critical value storage unit 100 also stores a map of the area where the piping network is arranged and data for displaying the piping network on the screen of the display device 302 of the damage occurrence position display unit 300.

For example, for the nth segment (N = n), the position data in the map of the nth segment is (x, y), the natural vibration period of the ground is T, the natural vibration wavelength is L, and the critical deformation is When the amount is Dcr and the flow critical deformation amount is δcr, the critical value storage unit 100 stores {N = n, (x, y), T, L, Dcr, δcr, as the data of the nth segment.
A maximum of seven types of data called "SIcr}" are stored as a group. Even when this data is read from the critical value storage unit 100, as described above, {N, (x, y),
T, L, Dcr, δcr, SIcr} are handled as a set of states. In addition, when the data used when the earthquake occurs is substantially four types of data of n, (x, y), SIcr, and δcr, other data that is not used is T, L, Dcr. Is stored separately as back data, and the critical value storage unit 100 stores {n,
The data (x, y), δcr, SIcr} may be stored as a group. This is desirable because the amount of data to be stored or read can be reduced.

The piping network is divided into a plurality of segments (N = 1, 2,
3) is divided into, for example, one side is 0.
It is possible to assume a square mesh of 5 [km], divide a predetermined area where the piping network is stretched by the mesh, and handle each individual mesh as each segment. Then, for example, the center point or centroid position of each segment can be used as the data (x, y) of the position of that segment in the map.

Here, the smaller the size of one side of the mesh is, the higher the positional accuracy becomes, but the number of segments increases and the labor of data processing tends to be complicated. On the contrary, as the size of one side of the mesh is increased, the number of segments is decreased and the labor of data processing is simplified, but the positional accuracy tends to be low. Therefore, it is desirable to set the size of the mesh to an appropriate size in consideration of the balance between the positional accuracy and the large number of segments. Further, since it is meaningless to set the mesh to a fine dimension such that the display dimension is too fine with respect to the display resolution of the screen of the display device 302 for displaying the map and the damage occurrence position, It is desirable to take the resolution of the display device 302 into consideration.

Alternatively, as will be described in detail later, paying attention to the connection form of the pipe (structural mechanical and geometrical pipe shape), the pipe network is formed into a straight line portion, a bent portion, and a T-shape. It is also possible to perform subdivision (discretization) based on a classification method such as classification into branched parts, and to handle each individual part as each segment. Also in this case,
For example, the position of the center point or centroid of each segment is used as the position data (x,
It may be used as y).

The data of the natural vibration period (T) or the natural vibration wavelength (L) of the ground can be obtained by conducting a boring survey for each important point of the ground in a predetermined area where the piping network is arranged. For example, in the Tokyo metropolitan area, Kanagawa prefecture, Chiba prefecture, and Saitama prefecture, which are the target areas for management, the ground for each key point where a gas conduit is installed is subjected to a boring survey at a total of tens of thousands of locations, and It is possible to obtain actual measurement values at each point. Alternatively, it goes without saying that existing (previously surveyed) data on the ground in the area where the pipe is arranged may be used.

Since an earthquake is a vibration phenomenon of the ground, if data of one of the natural vibration period (T) or the natural vibration wavelength (L) of the ground is obtained, based on the data. The other data can also be calculated. Therefore, data of at least one of the two may be obtained by a field survey. However, it is better to directly use the actual measurement value surveyed as ground data.
Value calculated based on actual measurement value (or indirect measurement value)
It is needless to say that it is more desirable from the viewpoint that the data can be expected to have higher accuracy than the above data.

The data of the critical deformation amount (Dcr) due to the direct vibration force (destructive force) of the earthquake and the data of the flow critical deformation amount (δcr) due to the fluidization of the ground caused by the earthquake are respectively obtained. Specific types of pipes for each segment (for example, welded steel pipes, ductile cast iron pipes, gray cast iron pipes, etc. for city gas pipe networks), caliber (inner diameter), material, and other specifications (for example, reinforcement treatment /
It can be obtained by performing a strength analysis of the pipe based on various data such as (not yet started).

Further, further, based on the strength analysis result of the piping, etc., the data of critical deformation amount (Dcr) and the data of flow critical deformation amount (δcr) were calculated, and the data were obtained by case study of past earthquakes. Calibration may be performed on the basis of information such as data of damage cases to further increase the reliability of the data.

More specifically, the critical deformation amount (Dcr),
The flow critical deformation amount (δcr) is essentially a numerical value (a physical amount such as an allowable stress or an allowable displacement) related to the structural mechanical strength of a pipe or a valve. Therefore, when the destructive force due to the vibration of an earthquake is applied to the piping network as an external force, structurally mechanical strength analysis of pipes and valves or a fracture experiment is conducted to theoretically or experimentally obtain an accurate critical deformation amount. The values of (Dcr) and flow critical deformation amount (δcr) can be obtained.

Regarding the method of analyzing the structural mechanical strength of the pipe or valve at that time, for example, the pipe in a certain segment is regarded as a tubular structure made of a predetermined metal material and The critical deformation amount (Dcr) and the flow critical deformation amount (δcr) can be obtained by performing a strength analysis by the finite element method on the structure.

Alternatively, taking the connection shape of the pipe into consideration, the pipe in one segment is classified into a straight line portion, a bent (curved pipe) portion, and a T-shaped branched portion. Then, it is also possible to obtain the critical deformation amount for each of the respective types and then adopt the minimum value of them as the data of the critical deformation amount (Dcr) in the segment. Also, the flow critical deformation amount (δ
Similarly for cr), the piping in one segment is
As described above, it is finely classified based on the connection shape, and the flow critical deformation amount is individually calculated for each individual type, and the minimum value among them is the flow critical deformation amount (δcr) in that segment. Can be used as the data of.

Based on the value of the critical deformation amount (Dcr) obtained as described above and the value of the natural vibration period (T) or the natural vibration wavelength (L) of the ground in the segment, the critical seismic motion value ( SIcr) or critical seismic amplitude value (U
cr) is required.

More specifically, as shown in FIG. 2 as an example, for a critical deformation amount (Dcr) of a certain pipe, a critical seismic amplitude value (or an allowable seismic amplitude value) at which the pipe begins to break. The critical seismic amplitude value (Ucr), which is, is uniquely determined. At this time, the value of the natural vibration period (T) or the natural vibration wavelength (L) of the ground where the pipe is buried
It has been confirmed that the graph (curve) showing the correspondence between the critical deformation amount (Dcr) and the critical seismic amplitude value (Ucr) is different. In other words, in general, for one pipe, there are two variables, the critical deformation amount (Dcr) of the pipe and the natural vibration period T) or the natural vibration wavelength (L) of the ground in which the pipe is buried. , The functional relation that one critical seismic amplitude value (Ucr) is determined (ie F
This means that (Dcr, T or L) = Ucr) holds (that is, F is a function, F (Dcr, T or L) = Ucr).

Therefore, for example, the critical deformation amount of the pipe in a certain segment is Dcr, and the natural vibration period of the ground in which the pipe is buried is T = 0.7 [s] (at this time, L = 20).
0 [m]), the value Ucr of the critical seismic amplitude value in that segment is T: as shown in FIG.
It can be obtained based on the curve in the case of 0.7 [s] (L: 200 [m]). Alternatively, for example, the natural vibration period of the ground is T = 1 [s] (at this time, L = 400 [m]).
In this case, the value of Ucr can be obtained based on a curve showing a more gradual monotonic increase as shown in FIG.

Here, since the earthquake is a ground vibration phenomenon, the critical seismic amplitude value (Ucr) and the critical seismic motion value (SIcr)
And, the relation expressed by the equation SIcr = 2π · Ucr / T is established. Therefore, using this relation,
From the critical seismic amplitude value (Ucr) obtained as described above, the critical seismic motion value (SIcr) can be obtained. The critical earthquake motion value (SIcr) thus obtained is finally used by the damage occurrence estimating unit 200 when estimating the presence or absence of damage to the pipe due to the earthquake.

Alternatively, the breakage occurrence estimating unit 2 is used to estimate the presence or absence of breakage of the pipe by using the critical seismic amplitude value (Ucr).
When 00 is set, the critical seismic amplitude value (Ucr) obtained as described above may be directly used. Therefore, in this case, the critical seismic intensity value corresponding to the critical seismic amplitude value (Ucr) is used. It goes without saying that the calculation of (SIcr) may be omitted.

Here, in recent years, the data of the seismic motion value (SI) observed in an earthquake is compared with other types of data.
It is easy to observe and obtain, and is extremely suitable for calculating the external force applied to piping. Therefore, in order to obtain and handle such data easily, the critical earthquake ground motion value (SIcr) is obtained in advance, and the critical earthquake ground motion value (SIcr) and the earthquake ground motion value (SI) observed at the time of the earthquake are calculated. Is preferably set so that the damage occurrence estimation unit 200 can compare.

On the other hand, regarding the data of the critical flow deformation (δcr), the critical flow deformation may be calculated for all the segments or all the pipes, but the fluidization of the ground due to the earthquake In the event of a spillage, the flow volume that causes pipe damage is actually limited to the vicinity of the revetment, and the displacement of the ground due to the fluidization near the revetment is caused on the revetment line. The present inventors have confirmed that the directions are almost orthogonal to each other in many cases. Therefore, for example, only pipes located in an area within 100 [m] from the seawall or segments having such pipes shall be treated as targets for damage occurrence estimation, and other pipes or segments should be treated as follows. The flow critical deformation amount (δcr) data may not be stored and the damage occurrence estimation operation based on the data may not be performed (omitted). By doing so, there is an advantage that at least the omitted data amount and data processing can be simplified.

The flow critical deformation amount (δcr) can be estimated by
Perform structural mechanical strength analysis of the pipe assuming that an external force is applied to the pipe from a direction almost orthogonal to the revetment line, which is the direction where the ground displacement is most likely to occur due to fluidization It goes without saying that it is desirable to seek by.

Further, when obtaining the data of the flow critical deformation amount (δcr), as in the case of the critical deformation amount (Dcr), connection of pipes such as a straight type, a curved pipe type, a T-shaped type, etc. The pipe network may be discretized into a plurality of segments based on a classification method focusing on the form, and strength analysis or the like may be performed for each of the segments.

Alternatively, the data of the flow critical deformation amount (δcr) is obtained in this way, and the flow critical seismic motion value (SIcr) that causes the flow critical deformation amount (δcr) is generated.
′) Or the flow critical seismic amplitude value (Ucr ′) is calculated based on, for example, the correlation or relational expression between the seismic intensity value and the flow amount, which has already been confirmed to hold.
Set the flow critical seismic motion value (SIcr ') or seismic amplitude value (Ucr') to compare with the seismic motion value (SI) or seismic amplitude value (U) observed when an earthquake actually occurred. Good.

However, it is needless to say that the flow rate (δ) actually generated when the earthquake occurs is not limited to this. Even if it is observed (measured) with image data or a displacement sensor for measuring the ground flow rate provided near the revetment, and the observed flow rate value δ and flow critical deformation value δcr are compared. Good.

The damage occurrence estimating unit 200 includes an SI comparison determining unit 201 and a δ comparison determining unit 202. When the earthquake occurs, the SI comparison and determination unit 201 compares the earthquake motion value (SI) observed in the earthquake with the critical earthquake motion value (SIcr) for each segment, and causes the earthquake to occur at that time. Then, it is estimated at which position the segment was damaged. Similarly, when the earthquake occurs, the δ comparison determination unit 202 also compares the flow rate (δ) observed or estimated in the earthquake with the flow critical deformation rate (δcr) for each segment or each predetermined segment. , It is estimated which segment of the pipe is damaged due to the fluidization of the ground caused by the earthquake at that time.

More specifically, when an earthquake occurs in the area where the piping network is installed, if the earthquake motion value (SI) observed in the earthquake is input to the damage occurrence estimating unit 200,
In the SI comparison determination unit 201 of the damage occurrence estimation unit 200, data {N, (x, y), T, L, Dcr, δcr, about all the segments stored in the critical value storage unit 100.
SIcr; N = 1,2,3 ...} is read out, and the seismic motion value (SI) and the critical seismic motion value (S) are calculated for each individual segment.
Icr) and the seismic motion value (SI) is greater than or equal to the critical seismic motion value (SIcr) (SIcr ≦ SI), it is determined that the segment is damaged, and the data at the position of the segment is damaged. It is sent to the generation position display unit 300.
However, if the seismic motion value (SI) is less than the critical seismic motion value (SIcr) (SIcr> SI), it is determined that the segment is not damaged. At this time, the data of the position of the segment is not transmitted.

It was also observed that when an earthquake occurred in the area where the piping network was installed, it occurred in an area within a predetermined distance from the revetment due to the fluidization of the ground caused by the earthquake. When the value of the flow rate (δ) is input to the damage occurrence estimation unit 200, the δ comparison determination unit 202 of the damage occurrence estimation unit 200 selects from among all the segments stored in the critical value storage unit 100, The data of the segment having the pipe within the predetermined distance from the above-mentioned revetment is selected and read out, and the flow amount value δ is read for each read out segment.
Flow rate (δ)
Is a flow critical deformation amount (δcr) or more (δcr ≦ δ)
It is determined that the segment is damaged, and the data of the position of the segment is displayed in the damage occurrence position display unit 300.
Send to. However, if the flow amount (δ) is less than the flow critical deformation amount (δcr) (δcr> δ), it is determined that the segment is not damaged.

The data of the seismic motion value (SI) and the flow rate (δ) observed when the above-mentioned earthquake occurs can be input even if the user manually sets the observation result, for example. It goes without saying that the data of the observation values sent by the relevant organization observing the earthquake may be automatically input.

Here, a critical seismic motion value (SIcr> SImax) larger than the seismic motion value (SImax) corresponding to the largest magnitude earthquake that can occur in a predetermined area, such as 200 [kine] or more, is set. It is possible to preliminarily presume that the owned segment is “constantly not damaged” because it is seismic-resistant even against such a maximum-scale earthquake. Similarly, when the critical seismic amplitude value (Ucr) is used instead of the critical seismic intensity value (SIcr), similarly, the critical seismic amplitude larger than the seismic amplitude value (Umax) corresponding to the largest magnitude earthquake that may occur. For segments with values (Ucr> Umax),
It may be preliminarily estimated that “there is no permanent damage”.

Thus, sufficient strength (SIcr or Uc
For pipes with r), it is preliminarily determined to be “constantly free from damage”, so that at least that amount of time and effort for comparing the seismic motion value (SI) with the critical seismic motion value (SIcr) (time and This is desirable because it is possible to omit (data processing), and further it is possible to further simplify the earthquake damage estimation method and further reduce the amount of data processing required for it.

Similarly, the damage due to the fluidization of the ground is the maximum that may occur near the seawall in a predetermined area where the piping network is provided, for example, 5 [m] or more. For a segment with a critical flow deformation amount (δcr> δmax) that is larger than the flow amount (δmax), it means that even if such maximum fluidization occurs, it will not be broken. It may be estimated in advance. Note that the above SImax = 20
It is needless to say that the values such as 0 [kine] and δmax = 5 [m] are given as examples, and are not limited to such numerical values in practice.

As for the segment thus estimated to be “constantly no damage”, information (for example, flag) indicating that it is not necessary to estimate the earthquake damage based on the seismic motion value and the flow amount is added to the segment. A set of data about {n, (x, y), T, L, Dcr, δcr, SI
It may be stored in the critical value storage unit 100 by additionally adding it in cr}.

The damage occurrence position display section 300 includes a data processing circuit 301 and a display device 302 as its main parts. In the damage occurrence position display unit 300, when an earthquake occurs, the data of the position of the segment where it is determined that the pipe is damaged due to the earthquake motion or the fluidization of the ground caused by the earthquake is the damage occurrence estimation unit 200. Then, the data processing circuit 301 causes the display device 302 to display the position data (x, y) of the transmitted segment and the map data of the entire area where the piping network is provided. Display data is created for pinpointing the position where damage is estimated to occur in the displayed map.

The display device 302 uses, for example, a liquid crystal display device capable of color display, and displays on its display screen.
An image of the map of the entire predetermined area and an image of the damage occurrence position indicated by pinpoints in the map are synthesized and displayed.
For example, the ground color of the entire map is green, and the piping network is classified according to pressure grades, for example, and different colors such as yellow and blue are shown for each classification. Then, in such a map, the position where the pipe is estimated to have been damaged when the earthquake occurs is displayed in a prominent warning color such as red. Further, the warning pinpoint display at the position where the pipe breakage occurs may be made to blink. Alternatively, it goes without saying that it is possible to show the segment in which the damage is estimated to occur in a planar manner (paint the segment in a different color from the other segments). The location of the damage caused by the earthquake motion and the location of the damage caused by the fluidization of the ground are displayed in different colors and blinking, so that the location of the damage and the cause of the damage can be seen at a glance. You may make it possible to determine.

Next, the main operation of the earthquake damage occurrence estimating apparatus according to the present embodiment will be described. FIG. 3 shows the flow of the main operation.

When an earthquake occurs, the earthquake motion value (SI) observed in the earthquake and the flow rate (δ) in a predetermined area near the revetment are input to the damage occurrence estimating unit 200 (S).
1). On the other hand, the data of each segment stored in the critical value storage unit 100 is read and input to the damage occurrence estimation unit 200 (S2), and the map data of the entire region is read and the damage occurrence position is read. It is input to the display unit 300 (S3). At this time, regarding a segment that has been previously determined to be “constantly not damaged”, the data of that segment may not be read (not shown).

Then, the damage occurrence estimating unit 200 compares the critical seismic motion value (SIcr) of each segment with the seismic motion value (SI) (S4). As a result, when the critical earthquake ground motion value (SIcr) is larger than the earthquake ground motion value (SI) (SI
If cr> SI) (N in S4), it is determined that the pipe is not damaged in that segment (S5). However, if the critical seismic motion value (SIcr) is less than or equal to the seismic motion value (SI) (SIcr ≦ SI) (Y of S4), it is judged that the segment is damaged due to the seismic motion. (S6), the data of the position of the segment is sent to the damage occurrence position display unit 300 (S7).

Similarly for the estimation of damage occurrence due to fluidization of the ground, the damage occurrence estimating unit 200 compares the flow critical deformation amount (δcr) of each segment with the flow amount (δ) (S8). At this time, regarding a segment that has been previously determined to be “constantly not damaged”, the data of that segment may not be read (not shown). Alternatively, only the data of the segment having the pipe within the predetermined distance from the seawall may be extracted and read, and the data of the other segments may not be read (not shown).

As a result of the comparison, when the flow critical deformation amount (δcr) is larger than the flow amount (δ) (δcr> δ)
(N in S8), it is determined that the pipe is not damaged in that segment (S9). However, when the flow critical deformation (δcr) is less than the flow (δ) (δcr ≤
δ) (Y of S8), it is determined that the segment is broken in the pipe due to fluidization (S10),
The data of the position of the segment is displayed in the damage occurrence position display section 3
To 00 (S7).

Subsequently, when the breakage occurrence position display section 300 receives the data of the position of the segment determined to have the breakage of the pipe, the data processing circuit 301 causes the data processing circuit 301 to send the data of the position of the segment. Based on (x, y) and the map data of the entire area where the piping network is provided, display data for pinpointing the damage occurrence position is created in the map displayed by the display device 302 (S11). ). Then, based on the display data, a map of the entire predetermined area and a position in which damage is estimated to occur in the map are combined and displayed on the screen of the display device 302 (S12).

For example, when the critical seismic motion value (SIcr) is in a distribution state as shown in FIG. 4 (A) for each pipe shape in a certain area, the seismic motion value SI = When an earthquake of 100 [kine] occurs, as shown in FIG.
Icr = 90 [kine] (that is, SIcr = 90 <SI
= 100), it is estimated that the valve portion is damaged, and this portion is pinpointed as the damage occurrence position. In FIG. 4 (B), this portion is indicated by a cross.

In this way, according to the earthquake damage occurrence estimating apparatus of this embodiment, the damage occurrence position of the pipe can be displayed, for example, in pinpoint on the map within the predetermined area where the pipe network is provided. Thus, the user can confirm at a position in the predetermined area where the breakage of the pipe is occurring, not in a probabilistic or statistical manner, but at a glance and accurately in real time.

By the way, when the structural mechanical strength analysis of the pipe is performed to obtain the data of the critical seismic motion value (SIcr) or the critical seismic amplitude value (Ucr) and the flow critical deformation amount (δcr), the connection of the pipe is performed. Focusing on the form, there are three types of a straight line part (straight line type), a bent part (bent tube type), and a T-shaped branched part (T-shaped type), or in addition to that, a T-shaped type The shape of the piping network is subdivided based on a classification method such as classifying the piping network into four types, with an H-shaped portion (H-shaped) in which the branch portions of are connected in close proximity ( As described above, the method of discretizing and analyzing the piping network is effective, in which the discretized) is considered (divided), and each discretized individual part is treated as each segment. This will be explained in more detail here.

When the method of discretizing and dividing the pipe network by the above-mentioned classification method is applied to the piping network having the shape shown in FIG. 5A, it is as shown in FIG. 5B. It can be discretized into each unit element. For each unit element discretized in this way, the structural mechanical strength analysis corresponding to each connection shape is individually performed (independently for each unit element) to obtain the critical seismic motion value (SIcr).
Alternatively, it is possible to obtain data on the critical earthquake amplitude value (Ucr) and data on the flow critical deformation amount (δcr). For material mechanical or structural mechanical strength analysis of the individual unit element conduits (for example, as a cylindrical structure) or valves (for example, as a flanged cylindrical structure), use the finite element method, for example. Needless to say, the strength may be confirmed experimentally by performing a strength test or the like.

In the case of the example of the piping network 400 shown in FIG. 5 (A), if the discretized total 16 unit elements are given identification numbers as shown in FIG. 5 (B). , Straight type is 4, 9, 14, 16 and curved tube type is 5, 7
No. 11, No. 11, T-shaped are No. 1, No. 2, No. 3, No. 6, No. 8, No.
No.10, No.15, and the H-shape that the T-shape is close
No., other than the various conduits on the left, the shape of the valve is 13
No., and the strength analysis is individually performed for each unit element to which each of these numbers (reference numerals 1, 2, 3 ... 16 in FIG. 5 (B)) is given, and each of them is analyzed. Obtain the critical (allowable) displacement amount (Dcr) or critical (allowable) stress value (Fcr), and based on that value, calculate the critical seismic motion value (SIcr) or critical earthquake amplitude value (Ucr) for each unit element. You can ask.

However, the only method for analyzing the strength of the pipe is to divide the pipe network by such discretization and to perform the strength analysis for each unit element which is the element of the minimum unit. It is not limited to Besides this,
For example, the entire piping network is regarded as a so-called wire frame model (FBD; free body tiregram) or mesh, and the finite element method is applied to the entire piping network, and the piping It is also possible to solve the so-called overall stiffness matrix for the entire network and perform strength analysis. Needless to say, the specific classification method for discretization is not limited to the above.

The purpose of the earthquake damage estimating apparatus and the earthquake damage estimating method according to the present invention is to divide a pipe network provided in a predetermined area into a plurality of segments, and for each of the segments, data on natural vibration of the ground and , Based on the data on the damage strength of the pipe and the data on the magnitude of the earthquake motion observed when an earthquake occurs in the specified area or the magnitude of the external force given by the earthquake, the damage to the pipe caused by the earthquake It is to estimate the presence or absence of occurrence, but it goes without saying that a specific apparatus or method based on this is not limited to the above-described modes. In addition to this, for example, the critical seismic amplitude value (Uc
r) is stored, and when an earthquake occurs, the earthquake amplitude value (U) observed in that earthquake and the critical earthquake amplitude value (Uc
It is also possible to estimate for each segment whether or not pipe damage has occurred due to the earthquake by comparing with r).

Further, in the above-mentioned embodiment, the critical seismic motion value (SIc
Although r) is calculated based on the critical deformation amount (Dcr) that causes pipe damage, it may be calculated based on the critical stress value (Fcr) that causes pipe damage. This also applies to the strength analysis regarding damage due to fluidization.

Needless to say, the estimation result of the presence or absence of breakage of the piping including the valve and the position where the breakage occurs is not limited to displaying on the screen of the display device as described above. In addition to this, for example, by printing out a map of a predetermined area and a damage occurrence position with a color printer or the like, or by printing out the coordinates of the damage occurrence position as character information instead of as an image such as a map. It is also possible.

[0101]

As described above, according to claims 1 to 1.
The method for estimating earthquake damage according to claim 3, or claim 1.
According to the earthquake damage estimation device described in any one of 4 to 29, it is probabilistic based on the statistical data about the magnitude of the past earthquake and the damage of the pipe caused by it as in the case of the conventional technique. Rather than estimating the occurrence of pipe damage, the data on the natural vibration of the ground where pipes such as gas pipes are installed, the data on the damage strength of the pipe, and the pipe network are arranged. Based on the magnitude of the earthquake motion observed when an earthquake occurs in the specified area or the data on the magnitude of the external force given by the earthquake, the presence or absence of pipe damage due to the earthquake occurred at that time, Estimated for each segment, or separately from it, data on pipe damage strength in the flow direction due to ground fluidization estimated when an earthquake occurs, and Based on the data on the flow rate observed or estimated when an earthquake occurs in the area, it is possible to estimate the occurrence of pipe damage due to the fluidization of the ground caused by the earthquake. , When an earthquake occurs, no matter what kind of earthquake it is, whether there is any damage to the pipes in the pipe network such as city gas or water,
In addition, if damage has occurred, the location of the damage can be estimated concretely and accurately rather than stochastically or statistically.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an earthquake damage estimation device according to an embodiment of the present invention.

FIG. 2 is a graph of a correspondence relationship between the value of the natural vibration period (T) or the natural vibration wavelength (L) and the critical deformation amount (Dcr) of the ground in which the pipe is buried, and the critical earthquake amplitude value (Ucr). It is a figure showing an example of (curve).

FIG. 3 is a diagram showing the flow of main operations of the earthquake damage occurrence estimation device shown in FIG. 1.

FIG. 4 shows the shape of the piping network and the result of its strength analysis (A), and SI = 100 [ki for the piping network.
FIG. 6 is a diagram illustrating an example of a damaged portion (B) estimated when an earthquake [ne] occurs.

FIG. 5 is a diagram showing an example of a shape (A) of a piping network and a method (B) in which the piping network is discretized into individual unit elements and divided.

[Explanation of symbols]

100 ... Critical value storage unit, 200 ... Damage occurrence estimation unit, 20
1 ... SI comparison determination unit, 202 ... δ comparison determination unit, 300 ...
Damage occurrence position display unit, 301 ... Data processing circuit, 302
… Display device

Continued front page    (72) Inventor Naoyuki Hosokawa             1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas             Within the corporation F term (reference) 3J071 AA02 AA12 BB11 CC02 EE16                       EE19 EE21 EE30 EE38 FF03                       FF12

Claims (29)

[Claims] 1. A pipe network provided in a predetermined area is divided into a plurality of segments, and data for the natural vibration of the ground, data for the damage strength of the pipe, and an earthquake occur in the predetermined area for each segment. Earthquake damage estimation characterized by estimating the occurrence of pipe damage due to the earthquake based on the magnitude of the earthquake motion observed during the earthquake or the data on the magnitude of the external force applied by the earthquake Method. 2. A pipe network provided in a predetermined area is divided into a plurality of segments, and for each segment, based on the natural vibration period or natural vibration wavelength of the ground and the critical deformation amount causing pipe damage, The critical seismic intensity value that is the critical seismic intensity value that causes damage to the pipe is determined in advance, and when an earthquake occurs in the predetermined area, the seismic intensity value observed in the earthquake is compared with the critical seismic intensity value. A method for estimating earthquake damage, characterized by estimating, for each segment, whether or not pipe damage due to the earthquake has occurred. 3. A pipe network provided in a predetermined area is divided into a plurality of segments, and for each segment, based on the natural vibration period or natural vibration wavelength of the ground and the critical deformation amount causing pipe damage, The critical seismic amplitude value, which is the critical seismic amplitude at which damage to the pipe occurs, is calculated in advance, and when an earthquake occurs in the predetermined area, the seismic amplitude value and the critical seismic amplitude value observed in the earthquake are calculated. In comparison, an earthquake damage estimation method characterized by estimating whether or not pipe damage due to the earthquake has occurred for each of the segments. 4. A pipe network provided in a predetermined area is divided into a plurality of segments, and for each segment, based on the natural vibration period or natural vibration wavelength of the ground and the critical stress value at which pipe damage occurs, The critical seismic intensity value that is the critical seismic intensity value that causes damage to the pipe is determined in advance, and when an earthquake occurs in the predetermined area, the seismic intensity value observed in the earthquake is compared with the critical seismic intensity value. A method for estimating earthquake damage, characterized by estimating, for each segment, whether or not pipe damage due to the earthquake has occurred. 5. The segment having a critical seismic intensity value larger than the seismic intensity value corresponding to the largest magnitude earthquake that may occur is estimated to be permanently damaged in advance. The earthquake damage estimation method according to item 2 or 4. 6. A segment having a critical seismic amplitude value larger than the seismic amplitude value corresponding to the largest magnitude earthquake that may occur is estimated to be permanently damaged in advance. The earthquake damage estimation method according to claim 3. 7. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is broken in the flow direction due to fluidization of the ground estimated when an earthquake occurs. An earthquake characterized by estimating the occurrence or non-occurrence of pipe damage due to the earthquake based on the data on the strength and the data on the flow rate observed or estimated when the earthquake occurs in the predetermined area. Damage estimation method. 8. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is damaged in the flow direction due to the fluidization of the ground estimated when an earthquake occurs. Is obtained in advance, when an earthquake occurs in the predetermined area, by comparing the critical deformation amount with the flow amount observed or estimated due to the fluidization of the ground due to the earthquake, A method for estimating earthquake damage, characterized in that the presence or absence of breakage of piping due to the earthquake is estimated for each of the segments. 9. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is broken in the flow direction due to the fluidization of the ground estimated when an earthquake occurs. Is calculated in advance, when an earthquake occurs in the predetermined area, based on the seismic motion value or the earthquake amplitude value observed in the earthquake, the flow rate caused by the fluidization of the ground due to the earthquake A method for estimating earthquake damage, characterized by estimating the flow rate and comparing the flow rate with the critical deformation rate to estimate the presence or absence of pipe breakage due to the earthquake for each segment. 10. The estimation of the occurrence of breakage of the pipe only in a segment of the pipe of the pipe network, the segment having a pipe within a predetermined distance from a seawall that is substantially affected by fluidization of the ground The method for estimating earthquake damage according to claim 8 or 9, wherein 11. When an earthquake occurs in the predetermined area,
Based on the seismic motion value or the seismic amplitude value observed in the earthquake, the flow rate in the direction orthogonal to the revetment is estimated as the flow rate caused by the fluidization of the ground due to the earthquake, and when the earthquake occurs, The earthquake damage estimation method according to claim 10, wherein a flow amount in a direction orthogonal to the revetment is estimated as a flow direction due to the estimated ground fluidization. 12. The pipe network is discretized into a plurality of segments by classifying the pipe network according to a predetermined classification method focusing on the connection form of the pipes, and the pipes caused by the earthquake are discriminated for each individual segment. The earthquake damage estimation method according to any one of claims 1 to 9, wherein the presence or absence of damage is estimated. 13. The earthquake damage estimation method according to claim 12, wherein, as the classification method, the connection form of the pipe is classified into a straight type, a curved pipe type, and a T-shaped type having a predetermined length or more. . 14. A pipe network provided in a predetermined area is divided into a plurality of segments, and data for natural vibration of the ground, data for damage strength of the pipe, and an earthquake occur in the predetermined area for each segment. Based on the magnitude of the earthquake motion observed at the time of the earthquake or the data on the magnitude of the external force given by the earthquake, the damage occurrence estimating means for estimating the occurrence of the damage of the pipe due to the earthquake was provided. Earthquake damage estimation device. 15. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is obtained based on the natural vibration period or natural vibration wavelength of the ground and the critical deformation amount causing pipe damage. A critical value storage means for storing a critical seismic motion value which is a critical seismic motion value causing damage to the pipe, and when an earthquake occurs in the predetermined area, the seismic motion value and the critical value observed in the earthquake. An earthquake damage estimating device comprising: a damage occurrence estimating means for comparing the seismic motion value and estimating whether or not the pipe is damaged due to the earthquake for each of the segments. 16. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is obtained based on the natural vibration period or natural vibration wavelength of the ground and the critical deformation amount causing pipe damage. A critical value storage means for storing a critical seismic amplitude value that is a critical seismic amplitude at which damage to the pipe occurs, and when an earthquake occurs in the predetermined area, an seismic amplitude value observed in the earthquake An earthquake damage estimating device comprising: a damage occurrence estimating unit that compares the critical earthquake amplitude value and estimates whether or not the pipe is damaged due to the earthquake for each of the segments. 17. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is obtained based on a natural vibration period or a natural vibration wavelength of the ground and a critical stress value causing pipe damage. A critical value storage means for storing a critical seismic motion value which is a critical seismic motion value causing damage to the pipe, and when an earthquake occurs in the predetermined area, the seismic motion value and the critical value observed in the earthquake. An earthquake damage estimating device comprising: a damage occurrence estimating means for comparing the seismic motion value and estimating whether or not the pipe is damaged due to the earthquake for each of the segments. 18. The segment having a critical seismic intensity value larger than the seismic intensity value corresponding to the largest possible earthquake is estimated to be permanently damaged in advance. The earthquake damage estimation device according to Item 15 or 17. 19. A segment having a critical seismic amplitude value larger than the seismic amplitude value corresponding to the largest magnitude earthquake that may occur is estimated to be permanently damaged in advance. The earthquake damage estimation device according to claim 16. 20. A pipe network provided in a predetermined area is divided into a plurality of segments, and each segment is damaged in the flow direction due to fluidization of the ground estimated when an earthquake occurs. A damage occurrence estimating means for estimating whether or not the pipe is damaged due to the earthquake based on the data regarding the strength and the data regarding the flow rate observed or estimated when the earthquake occurs in the predetermined area Earthquake damage estimation device characterized by 21. A pipe network provided in a predetermined area is divided into a plurality of segments, and pipes in a flow direction derived from the fluidization of the ground estimated when an earthquake occurs are obtained for each segment. Value storage means for storing a critical deformation amount that causes damage to the ground, and a flow amount and the critical deformation amount that are observed or estimated due to fluidization of the ground due to the earthquake when an earthquake occurs in the predetermined area. And a damage occurrence estimating means for estimating, for each of the segments, whether or not the pipe is damaged due to the earthquake, and an earthquake damage estimating device. 22. A pipe network provided in a predetermined area is divided into a plurality of segments, and the pipes in the flow direction due to the fluidization of the ground estimated when an earthquake occurs are obtained for each segment. Value storage means for storing the critical deformation amount that causes damage of the ground, and when an earthquake occurs in the predetermined area, based on the seismic motion value or the earthquake amplitude value observed in the earthquake, the fluidization of the ground due to the earthquake The flow rate resulting from the above is estimated, and the flow rate is compared with the critical deformation amount, and a breakage occurrence estimating means for estimating the presence or absence of breakage of the pipe due to the earthquake for each segment is provided. Earthquake damage estimation device characterized by 23. Estimating the presence / absence of breakage of the pipe only in a segment of the pipe of the pipe network, the segment having a pipe within a predetermined distance from a revetment that is substantially affected by fluidization of the ground. 23. The earthquake damage estimation device according to claim 21 or 22, wherein 24. When an earthquake occurs in the predetermined area,
Based on the seismic motion value or the seismic amplitude value observed in the earthquake, the flow rate in the direction orthogonal to the revetment is estimated as the flow rate due to the fluidization of the ground due to the earthquake, and when an earthquake occurs, The earthquake damage estimating device according to claim 22 or 23, wherein a flow amount in a direction orthogonal to the revetment is estimated as an estimated flow direction due to fluidization of the ground. 25. The pipe network is discretized into a plurality of segments by classifying the pipe network in accordance with a predetermined classification method focusing on the connection form of the pipes, and the seismic intensity is divided into the seismic regions by the individual discretized segments. The earthquake damage estimation device according to any one of claims 14 to 24, wherein the earthquake damage estimation device is configured to estimate whether or not pipe damage has occurred. 26. The earthquake damage estimating device according to claim 25, wherein the classification method is to classify the connection form of the pipe into a linear type, a curved pipe type, and a T-shaped type. 27. The critical value storage means stores, for each of the segments, data relating to a geographical position of the segment in the predetermined area and the critical seismic intensity value data in association with each other in advance, Damage occurrence estimation means, when an earthquake occurs in the predetermined area, by comparing the earthquake motion value observed in the earthquake with the critical earthquake motion value, the damage to the pipe caused by the earthquake,
18. The earthquake damage estimation device according to claim 15, wherein the position of the segment is estimated. 28. The critical value storage means is, for each of the segments, a critical value at which breakage of a pipe in a flow direction due to data on a geographical position of the segment in the predetermined area and fluidization of the ground occurs The amount of deformation is stored in advance in association with each other, and when the damage occurrence estimating unit compares an amount of flow observed or estimated in the earthquake with the amount of critical deformation when an earthquake occurs in the predetermined area. 23. The earthquake damage estimating device according to claim 21, wherein the position of the segment at which the breakage of the pipe caused by the earthquake occurs is estimated. 29. A map of the pipe network provided in the predetermined area is displayed, and the position of the segment where the damage is estimated to be caused by the damage occurrence estimating means when the earthquake occurs is displayed. 29. The earthquake damage estimating device according to claim 27, further comprising a damage occurrence position display unit displayed on the map.