JP7233197B2 - Pipeline network management system and its management method - Google Patents

Description

The present invention relates to a pipeline network management system and a management method thereof in the field of liquid supply as well as the water supply field.

As a technique for permanently installing a water leakage sensor in a pipeline to detect water leakage and managing the degree of deterioration of the pipeline, there is a technique disclosed in Patent Document 1. In the technique of Patent Document 1, water leakage is detected by a water leakage sensor installed in a water distribution network, and an aging characteristic graph of the pipeline is created from past water leakage record information to grasp the degree of deterioration of the pipeline over the years. .

WO2013/145493

In Patent Literature 1, although it is possible to detect water leakage by a water leakage sensor, there is no description about the effect of preventing the amount of water leakage. In addition, although the degree of deterioration of pipelines is estimated, consideration is not given to service life and life extension of pipelines. Furthermore, there is no mention of earthquake resistance (business entity needs).

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a management system for a pipeline network and a management method thereof, which are capable of ascertaining the amount of water leakage to be prevented and effectively managing the amount of water leakage.

In order to solve the above problems, one aspect of the pipeline management system of the present invention includes a storage device that stores the leakage flow rate as water leakage accident history data, and a sensor that is installed at a predetermined position in the pipeline network according to the performance of the water leakage sensor. It has a control unit that calculates the amount of water leakage prevention by the water leakage sensor when it is assumed to be arranged based on the water leakage accident history data, and a display device that displays the calculated amount of water leakage prevention.

According to the present invention, it is possible to predict and visualize the effect of water leakage prevention by constant water leakage sensing, and it becomes easy to control the amount of water leakage.

check later
The whole block diagram of a pipeline information management system. The figure which shows pipeline attribute data. The figure which shows water leakage accident history data. The figure which shows the node data of a pipeline. The figure which shows the annual water leakage amount in a water supply area. FIG. 4 shows stop valve data with respect to stop valve position; The figure which shows the sensor capability data of a water leakage sensor. The figure which shows the coefficient of the mathematical model for calculating a water leakage accident rate. The figure which shows the update base year data by pipe type. The figure which shows the risk display screen of a pipeline network. Explanatory drawing of water leakage investigation. The figure which shows the calculation result display screen of the water leakage loss prevention amount (amount). The figure which shows the flowchart of a water leakage loss prevention amount (amount) calculation program. Explanatory drawing of the water leakage amount growth by the water leakage estimation model. Explanatory diagram for calculating annual water leakage increase. The display screen of the calculation result of the pipe life extension years calculation process. The figure which shows the flowchart of a pipeline life extension years calculation process. The figure which shows the flowchart of an annual water leakage loss prediction program. The figure which shows the display screen of the prediction result of the future water leakage amount when life extension of a pipeline is not carried out. The figure which shows the display screen of the prediction result of the future water leakage amount at the time of life extension of a pipeline. The figure which shows the display screen of the calculation result of the capital-investment amount and the water-leakage loss amount accompanying pipeline renewal planning. The figure which shows the example of a display of the calculation result of the renewal reference years of each pipeline accompanying pipeline renewal plan formulation. The figure which shows the flowchart of a pipeline renewal planning process. The figure which shows the screen which displayed the calculation result of the capital investment amount and the seismic resistance rate according to a life extension control parameter accompanying pipeline renewal planning. The figure which shows the example which displayed the calculation result of the renewal reference years of each pipeline according to a life extension control parameter accompanying pipeline renewal planning. The figure which shows the flowchart of the process which performs pipeline renewal plan formulation according to a life extension control parameter.

<Overview of the invention>
Typical objects of the present invention are as follows.
To provide a pipeline system and a pipeline management method capable of grasping the amount of water leakage to be prevented and effectively managing the amount of water leakage.
Another object of the present invention is to provide a pipeline system capable of grasping an appropriate renewal timing of a pipeline based on the grasp of the amount of water leakage prevention and suppressing the capital investment amount by extending the life of the pipeline. to provide a management method for

Furthermore, another object of the present invention is to provide a pipeline system and a pipeline management method capable of creating a pipeline renewal plan that levels the pipeline investment amount, a pipeline renewal plan that takes earthquake resistance into consideration. is to provide

That is, according to the present invention, the following effects can be obtained.
It is possible to predict and visualize the effect of water leakage prevention by continuous sensing of water leakage, making it easier to control the amount of water leakage.
In addition, it is possible to determine the number of years to extend the service life of the pipeline so as to maintain the water leakage loss by making use of the water leakage prevention effect of the constant water leakage sensing. Since the pipeline can be used for a long period of time due to the extension of life, it is possible to reduce the capital investment for the pipeline.

Furthermore, while adjusting the parameters related to life extension, it is possible to grasp the behavior of the capital investment amount and the seismic resistance rate, which have a trade-off relationship. Planning becomes possible.

<System configuration>
An embodiment of the present invention will be described with reference to FIGS. 1 to 26. FIG.

FIG. 1 is an overall configuration diagram of a pipeline information management system of the present invention. The pipeline information management system 1 is composed of a storage device 11 comprising a RAM, a hard disk, etc., a control unit 12 comprising a CPU, etc., a man-machine interface such as a keyboard and a mouse, and a network interface for taking in data from an external network. It consists of a data input device 13 and a display device 14 such as a display.

The control unit 12 calls and executes the program 110 stored in the storage device 11 and displays the calculation result on the display device 14 . During the program execution process, data fetched from the data input device 13 and various information stored in the database 120 of the storage device 11 are referenced as necessary and used for calculation processing.

The calculation processing program 110 stores four programs. Leakage loss prevention amount calculation program 111 for calculating the amount of water leakage loss prevention, pipeline life extension evaluation program 112 for evaluating pipeline life extension years, annual leakage loss prediction program 113 for predicting future annual water leakage amount, pipeline renewal timing At the same time, it is a pipeline facility investment calculation program 114 that calculates the amount of pipeline facility investment. These are used to efficiently manage pipelines and leaks. Details of the processing will be described later. The database 120 contains pipeline attribute data (Fig. 2), water leakage accident history data (Fig. 3), management data of the coordinates of each node (Fig. 4), annual water leakage in the water supply area, etc. (Fig. 5), water stop valve Water stop valve data on the position of the water leakage sensor (Fig. 6), sensor capacity data of the water leakage sensor (Fig. 7), coefficients of the mathematical model for calculating the water leakage accident rate (Fig. 8), update base year data by pipe type (Fig. 9 ) are stored.

<Various data>
Main data stored in the database 120 are shown in FIGS. 2 to 9. FIG.

FIG. 2 shows pipeline attribute data 121 . Node information 212, 213, diameter 214, extension (pipeline length) 215, pipe type 216, year of installation 217, existence of polysleeve 218, renewal reference year 219, important It consists of information indicating that it is a pipeline 220 (large-diameter pipe, pipe on the route of an important facility, etc., which has a high degree of impact in the event of an accident) (○ indicates important management), and information such as the amount of unavoidable leakage 221 . Note that the pipe type 216 represents the material of the pipe. Pipe types include DIP (ductile cast iron pipe), SP (stainless water pipe), VP (vinyl pipe), and the like.

The update base year 219 is set according to guidelines for each business entity as shown in FIG. FIG. 9 shows update reference year data 912 of pipe type 911 . The unavoidable water leakage amount 221 is a theoretical value of the unavoidable water leakage amount.

For example, in FIG. 2, a pipeline with a pipeline number 211 of "1" has a node A 212 of "100", a node B of "102", a diameter 214 of "150 mm", and an extension 215 that is the length of the pipeline. is "50 m", the year of installation (installation year) 217 is "2000", there is a polysleeve coating 218, the renewal reference year 219 is "80 years", and the inevitable leakage amount 221 is " 1500 m ³ /year”.

FIG. 3 shows water leakage accident history data 301 . Accident occurrence date 312, pipe type 313, diameter 314, sleep coating presence/absence 315, location of occurrence (pipe No.) 316, installation year 317, leakage type (above ground, underground) 318, leakage flow rate 319 for each leakage accident , and the leakage prevention amount 321 . The amount of water leakage prevention 321 is the amount of water leakage that could be prevented in the year by water leakage repair, and is calculated by multiplying the amount of water leakage by the period from the occurrence of water leakage to the end of the year. In the water leakage accident history data of FIG. 3, an accident number is assigned each time a water leakage occurs, and information related to the accident such as the date of occurrence of the accident is stored.

FIG. 4 shows management data of the coordinates of each node corresponding to the node number as the node information of the pipeline. Information 412 corresponding to latitude and information 413 corresponding to longitude are managed in association with node numbers 411 that identify nodes. The information of each node is used when the pipeline network is illustrated on a two-dimensional plane.

FIG. 5 shows the actual data of the annual water leakage amount and the annual water leakage prevention amount in the water supply area, and the figure shows only the past four years. The water supply area shown in FIG. 5 is, for example, one city as a unit, and is composed of a plurality of pipeline networks.

FIG. 6 shows water stop valve data relating to the position of the water stop valve. In addition to the numbers 612 and 613 of the water stop valve nodes (see FIG. 4), it is possible to determine whether a water leakage sensor is installed at each water stop valve. Information 614 is also included. For example, a sensor is arranged at the stop valve number "1".

FIG. 7 shows sensor performance data of the water leakage sensor to be utilized. Sensor intervals required for water leakage detection are shown for each pipe type and pipe diameter. If the sensors are installed at this interval, all leaks in the pipeline network where the sensors are installed can be detected. For example, when the pipe type 711 is "DIP, SP" and the diameter 712 is "75 to 200 mm", the sensor interval 713 is "300 m".

FIG. 8 shows the coefficients of the mathematical model for calculating the water leakage accident rate. For pipe types DIP and SP, the water leakage accident rate f(t) (number of cases/km/year) is calculated based on the following formula.

ｔ：管路の供用年数、ａ、ｂ：図８で示した係数、e：自然対数

t: service years of pipelines, a, b: coefficients shown in Fig. 8, e: natural logarithm

On the other hand, for pipe types CIP (cast iron pipe) and VP (hard vinyl chloride pipe), the accident rate formula is as follows. In order to use this mathematical model, among the management attribute data shown in FIG. 2, at least the pipeline node information, the pipeline length (extension), and the installation year are required.

The database storage information shown in FIGS. 2 to 9 is stored as the database 120 in FIG. 1 and used for various arithmetic processing of the four programs (111, 112, 113, 114).

In Equations 1 and 2, the number of water leakage accidents per unit length of pipeline can be obtained from the years of service of the pipeline. In addition, the water leakage flow rate can be obtained by the expected value of the annual water leakage rate per unit length using Equation 5. Details will be described later.

Therefore, by using mathematical models such as Equations 1, 2, and 5 in place of the actual water leakage accident history data, it is possible to obtain the amount added to the amount of water leakage loss prevention by the water leakage sensor shown in Equation 4. That is, it is possible to obtain the amount of water leakage prevention by the water leakage sensor when it is assumed that the sensor is arranged at a predetermined position in the pipeline network according to the performance of the water leakage sensor, using a mathematical model.

<Leakage loss prevention amount calculation program>
Next, processing contents of the program 111 for calculating the amount of water leakage loss prevention will be described based on FIGS. 10 to 13. FIG. This processing is to calculate the effect of the conventional manual water leakage investigation and countermeasures and the water leakage detection and countermeasures by the water leakage sensor (leakage loss prevention effect).

FIG. 13 is a flow chart of the water leakage loss prevention amount calculation program 111 .
At step 1301 , calculation conditions specified by the user are read through the data input device 13 . Calculation conditions specified by the user include information on how many years of past water leakage history data to use (specify 5 years here), pipe type information on pipelines where water leakage sensors are installed (specify DIP here), water supply Leakage survey cycle information in the area (here, a 3-year cycle is specified. The 3-year cycle means that, as shown in Fig. 11, the entire water supply area is divided into three, area A for this year, area B for the next year, and area B for the next year. area C, then area A, etc.) and water cost information (here, set at 175 yen/ ^m3 ).

At step 1302, the pipeline attribute data 201 (FIG. 2) of the target pipeline (here, DIP) is read.

In step 1303, referring to the data in FIG. 8, the coefficients of the mathematical model (coefficients of the accident rate model) for calculating the water leakage accident rate of the target pipeline (here DIP) are read.

In step 1304, the accident rate of the DIP pipeline is calculated from the number of years in service of the pipeline (the number of years in service is calculated from the year of installation) using Equation 1, and the result (result of accident rate calculation) is shown in FIG. indicate.

FIG. 10 is a diagram showing the risk display screen of the pipeline network, and the line is the pipeline network and the magnitude of the accident rate is shown in (grayscale), but in reality it is displayed in color. good. The accident rate occurrence expected value in FIG. 10 is displayed, for example, by changing the scale in units of "0.1", from "0.1" where the expected value is small to "0.5" or higher where the expected value is large. With reference to this figure, we will examine how many accident rates pipelines should be installed with water leakage sensors. A plurality of pipeline networks shown in FIG. 10 constitute one water supply area.

At step 1305, the user specifies and inputs the accident rate. That is, among the expected accident rate values shown in FIG. 10, a pipeline network with a high expected value is regarded as a pipeline with a high risk, and filtering is performed to preferentially perform water leakage treatment. Therefore, it is assumed that a water leakage sensor is installed in a pipeline having an accident rate higher than the expected accident rate specified by the user.

In step 1306, after grasping the sensor capacity (installation interval) in FIG. The position is calculated, and the presence/absence of arrangement (o mark) is written as shown in FIG.

In step 1307, referring to the water leakage accident results in FIG. 3, the number of ground water leaks N1, the number of underground water leaks N2, the average ground water leakage flow rate Q1, and the average underground water leakage flow rate Q2 for each past year are calculated.
Number of ground leaks N1: A value obtained by counting water leaks occurring on the ground from the water leakage accident history data recorded in FIG.
Number of underground leaks N2: A value obtained by counting underground leaks from the leak accident history data recorded in FIG.
Ground leakage average flow rate Q1: The average value of the leakage flow rate 319 occurring on the ground from the water leakage accident history data recorded in FIG.
Average underground leakage flow rate Q2: The average value of the underground leakage flow rate 319 from the water leakage accident history data recorded in FIG.

In addition, the amount of water leakage prevention (amount) due to the investigation measures in the conventional 3-year cycle is calculated by the following formula.

The conversion factor for the annual leakage amount of flow rate is to convert the unit of leakage flow rate (l/min) in Fig. 3 to the unit (m3/year) and match it with the unit of water cost (yen/ ^m3 ). be.
The coefficient of 0.5 is because it is considered that if not prevented, a leak will be left unattended for an average of 0.5 years and become a loss. The amount of water leakage prevention by the conventional method can also be calculated by taking the average for the past five years using the values shown in FIG.

In addition, since underground water leakage can be detected at an early stage by using the water leakage sensor, the extra water leakage prevention amount (amount) due to the permanent installation of the water leakage sensor is calculated by the following formula.

The coefficient of 1.5 is because the conventional inspection cycle is three years, and even if a leak becomes detectable, it is considered to be left for an average of 1.5 years, resulting in a loss. Since this water leakage loss can be prevented by constant sensing, it is added to the amount of prevention due to the permanent installation of the sensor. Note that the conversion factor for the flow rate to the annual leakage amount is the same as Equation 3.

In step 1308, the calculation result display screen of the water leakage loss prevention amount shown in FIG. 12 is output.
A display area 1201 for user setting conditions input in step 1301, a display area 1202 for water leakage loss prevention amount calculation, a display area 1203 for past water leakage prevention results, and a display area 1204 for average water leakage amount results are shown.

For the average number of accidents in Equations 3 and 4, the expected number of accidents can be calculated by multiplying the accident rate obtained in Equation 1 by the length of the pipeline for the target pipeline without using actual data. . You can use this as an alternative value. Further, the water leakage amount can be obtained by using Equation 5, which will be described later, to obtain the annual water leakage amount per unit extension. From Equations 1 and 2, the number of accidents per year per unit extension can be obtained, and from Equation 5, the water leakage flow rate per year per unit extension can be obtained. In this way, using the mathematical models of Equations 1, 2, and 5, instead of the leakage accident history data, the amount of water leakage is obtained, and by applying Equations 3 and 4, the amount of water leakage loss prevention is obtained from the mathematical model. be able to.

In this way, the water leakage loss prevention amount calculation program 111 calculates the amount of water leakage prevention by the water leakage sensor when it is assumed that the sensor is arranged at a predetermined position in the pipeline network according to the performance of the water leakage sensor. Calculated from a mathematical model.

In the display area 1202 of FIG. 12, the leakage loss prevention amount is displayed as a result of the water leakage countermeasure. You can easily compare it with the amount of investment required to install it.

<Pipe service life extension evaluation program>
14 to 17, a calculation process for pipe life extension years (pipe line life extension evaluation program 112) utilizing the leakage prevention effect of constant water leakage sensing will be described. When the life of a pipeline is extended (deteriorated), the expected value of leakage from the pipeline generally increases. Before describing the calculation process, a model for calculating this increment will be described.

FIG. 14 is an explanatory diagram of the leakage amount growth by the leakage estimation model. FIG. 14 shows a model for estimating the amount of leakage of pipe attribute (pipe type). In this model, the expected value of the annual water leakage amount from the unit extension starts from the unavoidable water leakage amount Q0 and increases exponentially (see 1401 in FIG. 14). Expressed as a formula, it is as follows.

ここに、Ｑ：漏水量期待値（m3/ｋｍ/年）、ｔ：供用年数、Ｑ０：不可避漏水量、ｂ：漏水増加スピードを規定する定数、ｅ：自然対数である。

Here, Q: expected value of leakage (m3/km/year), t: number of years in service, Q0: amount of unavoidable leakage, b: constant that defines the rate of increase in leakage, and e: natural logarithm.

Once repaired, the amount of water leakage drops to the level of unavoidable water leakage (Fig. 14, t0), but then the amount of water leakage grows at the same speed as before the repair (1402 in Fig. 14). A curve 1402 is an extension of the curve 1401 before repair. Regardless of whether or not repairs are made, the water leakage rate remains unchanged, and the older the pipe, the faster the water leakage rate increases. The amount of water leakage increase in a pipe type (for example, DIP) in a water supply area can be calculated from the DIP model and the attribute data of the DIP pipe (service years and pipe length) using the following formula.

ΔQtotal: annual increase in total leakage from all DIP pipes in the water supply zone, t: service years, l: total pipe length, ΔQ: annual increase in leakage per unit length. Here, it is assumed that there are no pipes that have been in service for 71 years or more. In order to use Equations 5 and 6, values of constants Q0 and b are required.

The unavoidable water leakage Q0 can be calculated from the number of pipeline nodes, the length of the water supply pipe, the average water pressure of the target pipeline, etc., according to the IWA formula. Also, for b, the differential value (annual leakage increase) of Equation 5 is equal to the structure of the formula for the leakage accident rate (the number of new leakage accidents per year), so the same coefficient (0.0582 in Fig. 8 for DIP) is approximated. used for purposes. This coefficient can be calculated from the annual leakage amount and the annual leakage prevention amount as shown in Fig. 15, which is an explanatory diagram for calculating the annual leakage increase amount. By fitting, b can be estimated. When the water supply area consists of a plurality of types of pipes, there are a plurality of parameters b for each type of pipe, but it can be calculated by establishing simultaneous equations regarding the increase in water leakage in the plurality of water supply areas.

FIG. 17 shows a flowchart of the life extension possible years calculation process.
At step 1701, calculation conditions are taken. Here, the analysis object pipe type information (for example, DIP) specified by the user is read.

In step 1702, the water leakage loss prevention amount calculation program 111 calculates the water leakage loss prevention amount of the target pipeline. Next, in step 1703, referring to the pipeline attribute data (Fig. 2) such as the length of the pipe type to be analyzed and the year of installation, this and Equation 6 are used to calculate the total annual water leakage when the pipeline life of the target pipe type is extended. Calculate the amount increase (=annual new leakage amount).

In step 1704, as shown in FIG. 16 (display screen of calculation result of pipe life extension years calculation processing), a graph 1602 of water leakage loss prevention amount and a graph of new water leakage occurrence amount 1601 are displayed on the display device 14, and the intersection Calculate and present the life extension years from

FIG. 16 shows the case where life extension is started at 0 years, and water leakage constant sensing is started in addition to the conventional water leakage investigation. Since 2002, the amount of water leakage prevention by constant sensing has been added, and the amount of prevention has been stepped up. On the other hand, the amount of new leaks will gradually increase due to the extension of service life (pipeline aging) after 0 years. This is because the number of service years t used in Equation 6 increases due to aging as years pass.

During the period in which the amount of prevention exceeds the amount of newly generated leakage, the annual leakage loss is maintained, so it is assumed that the life of the pipeline can be extended only during this period. This is because the following equation holds.

This year's annual water leakage loss = Previous year's annual water leakage loss + (annual new water leakage amount - annual water leakage prevention amount) x water cost

In FIG. 16, the length of life extension is 10 years. During this period, the water leakage loss is maintained even if the pipeline is used to extend its life, so the capital investment in the pipeline can be reduced by the extension of the pipeline's life, and a large cost reduction can be realized.

In FIG. 16, the amount of water leakage prevention was calculated by the water leakage loss prevention amount calculation program. Here, the amount of prevention was calculated in the case of manually inspecting water leakage every three years and constantly sensing water leakage with a new water leakage sensor. In addition, various water leakage countermeasures are conceivable, and the amount of prevention by them may be calculated in advance and utilized as an input (graph of 1602) of this process to calculate the life extension years.

<Annual Leakage Loss Prediction Program>
Next, the processing contents of the program 113 for predicting the future annual water leakage amount in the water supply area are calculated based on FIGS. 18 to 20. FIG.

In this process, FIG. 18 is a flow chart of an annual water leakage loss prediction program for predicting the future annual water leakage amount. In step 1801, user-set information such as parameters k, k1, and k2 required for calculation, pipeline life extension start time, pipeline life extension years (eg, 10 years), and calculation period (eg, 50 years) are set as calculation conditions. read as The meaning of the parameters will be described later.

At step 1802, a parameter T representing time is set to zero. At step 1803, referring to FIG. 5, the latest annual water leakage data QL(T) is fetched.

In step 1804, the annual new water leakage amount QN(T+1) in the next year (T+1) is calculated with reference to Equation 6. Formula 6 is for DIP, but calculations for other types of pipes are also performed using similar formulas, and the sum of the results is obtained. The calculation of Equation 6 requires data on the total pipeline length for each service year at T+1. It is necessary to calculate the future total length based on the future pipeline renewal plan and use it in Equation 6. At step 1805, the annual water leakage prevention amount QP(T+1) in the year (T+1) is calculated by the following equation.

Here, k1 and k2 are constants determined depending on the conventional water leakage investigation method (inspection conducted by a person every 3 years), and k is a new investigation method in addition to the conventional investigation method (here, water leakage by a water leakage sensor is constant). sensing). In this calculation, k=1.15, k1=0.09, and k2=0.1.

The value of k can be calculated by (calculated value of Equation 3+calculated value of Equation 4)/calculated value of Equation 3. For k1 and k2, from the time-series data of the annual leakage amount QL and the annual leakage prevention amount QP (prevention amount by the conventional investigation method) in Figure 5, using the relationship in Figure 15, the annual leakage newly derived amount (= annual Increase in water leakage) QN is calculated, and k1 and k2 are determined using the least squares method so that the time series data fit the following equation.

Note that k1 is a constant indicating the ratio of how much the existing leak at time T grows and becomes detectable at time (T+1), and k2 is the ratio of how much of the newly derived leak can be detected. constant. Since these parameters depend on the leakage investigation method, it is necessary to calculate and use them for each investigation method.

In step 1806, the annual leakage amount QL(T+1) of the water supply area at time (T+1) is calculated by the following equation.

At step 1807, it is determined whether or not T has reached a predetermined value (calculation end time, 50 years since the calculation period is 50 years in this example). , T is incremented by 1, and the processing from step 1804 to step 1807 is repeated.

19 and 20 show display screens of prediction results of the future water leakage amount.
FIG. 19 shows a display screen of the prediction result of the future water leakage amount when the service life of the pipeline is not extended. FIG. 19 shows the result of the water leakage investigation by the conventional method up to year T0 and the constant sensing by the water leakage sensor after T0+1. It can be seen that the annual total water leakage amount 1903 in the water supply area is gradually decreasing due to the new water leakage countermeasures. In addition, the difference between the amount of water leakage prevention 1901 and the amount of water leakage new occurrence 1902 makes it possible to grasp the effect of water leakage countermeasures in which constant sensing by the water leakage sensor is added.

FIG. 20 is a display screen of the prediction result of the future water leakage amount when the service life of the pipeline is extended. In Fig. 20, it is assumed that the water leakage investigation by the conventional method is performed up to fiscal year T0, and new water leakage countermeasures using a water leakage sensor (constant detection of water leakage by a water leakage sensor) are added after T0+1, and the pipeline is installed for only 10 years from T0+1 to T0+10. It is a simulation result when life extension is carried out. The amount of newly generated water leakage 2002 increases due to the aging of pipelines, but the amount of water leakage prevention 2001 also increases due to new water leakage countermeasures. I understand.

<Conduit facility investment calculation program>
Next, the contents of the processing of the program 114 for calculating the pipeline facility investment amount at the same time as the pipeline renewal timing will be described with reference to FIGS. 21 to 26. FIG. This processing is for calculating the pipeline renewal timing for leveling the future pipeline equipment investment while taking into consideration the life extension of pipelines. As shown in FIG. 2, each pipeline is assigned a renewal reference year, but if pipeline renewal is performed according to this, it is undesirable because some years will appear with more investment and some years will have less investment. It is necessary to allocate the renewal of pipelines in the year when the investment is high to the years before and after to level the investment.

FIG. 23 shows a flow chart of pipeline renewal plan planning processing for formulating a renewal plan for realizing investment leveling while considering life extension and displaying the results.

In step 2301, user setting conditions are read. Here, the pipeline (pipe type) that is the target of the renewal plan designated by the user, the values of renewal year constraint adjustment parameters α and β, and the facility investment constraint adjustment parameter γ are read.

At step 2302, the following planning problem is solved to calculate the renewal timing of the target pipeline.
(1) Maximization of the total number of life extension years of the objective function

Minimization of average capital investment during the period

(2) Upper and lower limits of constraint update base year

Upper and lower limit of investment amount

(3) Variable pipeline numbers: 1, 2, ………, N
Renewal years of pipelines 1 to N: T1, T2, ... TN
Renewal cost of pipelines 1 to N: C1, C2, ... CN
Year of investment: t (t=0 represents the current year, t=1 the next year, and t=2 the next year)
Investment amount from year 1 to year t: I(1), I(2), ……, I(t)
Investment limit for 1 year to t years: Iu(1), Iu(2), ……, Iu(t)
Original update base years for pipelines 1 to N: To1, To2, ……, ToN
Installation years of pipelines 1 to N: Tb1, Tb2, ……, TbN
Extendable years of pipelines 1 to N: Te1, Te2, ………, TeN
Capital investment other than DIP from year 1 to year t: Io(1), Io(2), …………Io(t)
Investment period: 1 to TE
Set of pipeline numbers of important pipelines: Np
Positive constants: α, β, γ

Here, with DIP as the object, a renewal reference year for each pipeline is newly calculated while taking life extension into account. The original update base year, which is one of the variables, is the originally set update base year as shown in FIG. In consideration of the number of years Tei (i=1 to N) that can be extended, a new renewal reference year Ti (i=1 to N) for leveling the investment is calculated. As the objective function, the maximization of the total number of life extension years in the number 10 and the minimization of the annual average of the investment in the number 11 are adopted. As the constraint conditions, the upper and lower limits of the update base year and the upper and lower limits of the investment amount are provided in Equations 12 and 13.

Formula 13 is the update base year constraint for important pipelines, and its upper and lower limits are smaller than the base year constraint for normal pipelines in Formula 12 by the variable β. β is a user setting parameter and is set to a value of about 10, for example. α sets the width of the upper and lower limits, and is set to about 10, for example.

This is the upper and lower limits of investment, and the width is set by the parameter γ. For example, γ is set to about 0.9. At step 2302, the new renewal base year for each pipeline is obtained by solving this planning problem. An example of a newly planned update base year is shown in FIG. FIG. 22 is a diagram showing a display example of the calculation result of the renewal reference years for each pipeline associated with pipeline renewal planning. The renewal base year is the original base year, the modified renewal base year is the base year considering the number of years of life extension (here, 10 years), and the modified renewal base year (with investment leveling) is calculated by solving the planning problem. This is the base year for the planned pipeline renewal.

In step 2303, referring to the update plan in step 2302, the future water leakage amount of the water supply area is predicted by the method described in the annual water leakage loss prediction program.

Finally, in step 2304, as shown in FIG. 21, the equipment investment amount based on the renewal plan and the annual leakage loss amount are displayed. In the investment amount graph 2101, the conventional method 20111 uses the original renewal year, the proposed method (without leveling) 21012 uses the modified renewal base year considering life extension, and the proposed method (with leveling) 21013 This is the result when using the revised renewal base year considering life extension and leveling.

The annual leakage loss amount 2102 is shown by the proposed method (without leveling) 21022 and the proposed method (with leveling) 21023 for the conventional method 20121 .

In the proposed method (without leveling) that adds water leakage countermeasures by constant sensing with water leakage sensors, and in the proposal method that leveled the investment in addition to the water leakage countermeasures by constant sensing with water leakage sensors (with leveling), these measures are implemented. It can be seen that the amount of capital investment is reduced compared to the conventional method that does not carry out, and that the investment is leveled with leveling.

Along with these results, the average life extension years and average capital investment amount of the proposed method (with leveling) are calculated. The former is calculated by calculating the total number of years of service life extension with Equation 10 using the determined renewal year and dividing it by the number of pipelines N. Moreover, the latter can be obtained by calculating the investment average amount in Equation 11 using the determined renewal year.

The above method can be used to find a base year for renewal that will level out the investment while prolonging the life of pipelines. The longer the service life is, the less the capital investment will be, but the delay in renewal of pipelines will also delay the progress of seismic retrofitting. The processing program of FIG. 26 (flowchart of the processing for formulating a pipeline renewal plan according to the life extension suppression parameter) can be used in order to formulate a renewal plan while taking earthquake resistance into consideration. Here, the following constraint equation using a life extension suppression parameter ΔT (positive constant) is used as a constraint condition for the aforementioned planning problem.

At step 2601 in FIG. 26, data similar to that at step 2301 in FIG. 23 is read. In step 2602, instead of Equations 12 and 13, the constraints of Equations 15 and 16 are used to solve the planning problem (determining the renewal year of the pipeline). Here we solve the planning problem with .DELTA.T=0 and some positive value, for example .DELTA.T=5. ΔT is information input by the user through the data input device 13, and can be considered as a value that suppresses extension of life.

An example of the result of solving the planning problem is shown in FIG. 25 (an example of displaying the calculation result of the renewal reference years of each pipeline according to the life extension suppression parameter) associated with the formulation of the pipeline renewal plan. In the case of ΔT = 5, life extension is suppressed, so the corrected renewal base year (with leveling) obtained is smaller than the corrected renewal base year (with leveling) in the case of ΔT = 0. I know you are.

In step 2303, based on the proposed pipeline renewal plan for the next fiscal year and thereafter, the ratio of the total extension of earthquake-resistant pipelines to the total pipeline extension is calculated for each future year. It is assumed that all pipelines to be renewed will be made earthquake resistant.

At step 2304, as shown in FIG. Displays a transition graph of pipeline equipment investment amount and a graph of seismic resistance rate transition based on the renewal plan. The equipment investment for ΔT=0 is 24012 and the earthquake resistance rate is 24022, and the equipment investment for ΔT=5 is 24011 and the earthquake resistance rate is 24021.

It can be seen that if ΔT is increased to suppress life extension, the amount of capital investment will increase, but the speed of the seismic resistance rate will increase. This graph supports decision-making (what value should be used as ΔT) for renewal planning considering the trade-off between capital investment and earthquake resistance rate (or life extension and earthquake resistance).

In this way, since the relationship between the earthquake resistance rate and the amount of capital investment can be displayed, it is possible to make a decision on capital investment in consideration of the earthquake resistance rate.

1: pipeline management system, 11: database, 12: control unit, 13: data input device, 14: display device, 110: calculation processing program, 111: water leakage loss prevention amount calculation program, 112: pipeline life extension evaluation program , 113: annual leakage loss prediction program, pipeline equipment investment calculation program 114;

Claims (5)

In the management system of the pipeline network that constitutes the water supply area,
a storage device for storing water leakage flow rates as water leakage accident history data for pipelines constituting the pipeline network;
The first amount of water leakage prevention due to investigation measures and the amount of water leakage prevention due to the permanent installation of the water leakage sensor when it is assumed that the water leakage sensor is placed at a predetermined position in the pipeline network according to the performance of the water leakage sensor. a control unit that calculates the water leakage prevention amount of 2 based on the water leakage accident history data;
a display device for displaying the first water leakage prevention amount and the second water leakage prevention amount calculated by the control unit;
The control unit
Calculate the first water leakage prevention amount by multiplying the past water leakage average of the water leakage accident history data by the average number of years that the water leakage is left unchecked and the water cost ,
A pipeline management system, wherein the second water leakage prevention amount is calculated by multiplying the past water leakage average of the water leakage accident history data by half the number of years of the water leakage investigation cycle and the cost of water as a coefficient. The storage device
For pipelines constituting the pipeline network, pipeline attribute data including at least a pipeline type, pipeline node information, pipeline length, and installation year, and to calculate a water leakage accident rate for each pipeline type Store the coefficients of the mathematical model of and the ability of the water leakage sensor,
The control unit
The second water leakage prevention amount is replaced with the water leakage accident history data, and the water leakage accident rate per year is calculated for the pipelines constituting the pipeline network using the mathematical model, and the calculated water leakage is calculated. 2. The pipeline management system according to claim 1, wherein the expected number of accidents calculated by multiplying the accident rate by the pipeline length is used for calculation. The control unit
calculating an expected leakage amount based on the unavoidable leakage amount of the target pipeline of the pipeline network and the service life;
calculating an annual new leakage amount in the water supply area based on the expected water leakage amount, the number of years of service of the target pipeline, and the total length of the target pipeline for the pipelines constituting the pipeline network;
2. The pipeline management system according to claim 1, wherein the time point when said annual new leakage amount exceeds said first and second leakage prevention amounts is displayed on said display device as the life extension years of said pipeline. . In a method for managing a pipeline network constituting a water supply area using a management system having a storage device, a control unit, and a display device,
The storage device stores, as water leakage accident history data, a water leakage flow rate for the pipelines constituting the pipeline network, and further stores at least pipe type, pipeline node information, pipeline length, and installation year. store the pipeline attribute data including, the coefficient of the mathematical model for calculating the water leakage accident rate for each pipe type, and the ability of the water leakage sensor,
The control unit provides a first water leakage prevention amount by investigation measures and a water leakage prevention amount by permanent installation of the water leakage sensor when it is assumed that the water leakage sensor is arranged at a predetermined position of the pipeline network according to the ability of the water leakage sensor. Calculate the second water leakage prevention amount as an additional amount based on the water leakage accident history data,
The first water leakage prevention amount is calculated by multiplying the past water leakage average of the water leakage accident history data by the average number of years that water leakage is left unchecked and the cost of water ,
The second water leakage prevention amount is calculated by multiplying the past water leakage average of the water leakage accident history data by half the number of years of the water leakage investigation cycle and the water cost as a coefficient,
The pipeline network management method, wherein the display device displays the first water leakage prevention amount and the second water leakage prevention amount calculated by the control unit. The storage device
For pipelines constituting the pipeline network, pipeline attribute data including at least a pipeline type, pipeline node information, pipeline length, and installation year, and to calculate a water leakage accident rate for each pipeline type Store the coefficients of the mathematical model of and the ability of the water leakage sensor,
The control unit
The second water leakage prevention amount is replaced with the water leakage accident history data, and the water leakage accident rate per year is calculated for the pipelines constituting the pipeline network using the mathematical model, and the calculated water leakage is calculated. 5. The pipeline network management method according to claim 4, wherein the calculation is performed using an expected number of accidents calculated by multiplying the accident rate by the pipeline length.

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