Road maintenance management planning support system

Abstract

To provide a road maintenance management planning support system that can be applied even when historical information is not organized or stored in a database, for an item managed over a wide area in a planar manner, in the formulation of a road maintenance management plan using mathematical optimization.SOLUTION: A system divides a road to be repaired into a plurality of segments, and uses the element information of the road to be repaired and a soundness score indicating the condition of the road to be repaired. For each of the plurality of segments, the system calculates a weighted soundness score after repair by multiplying the post-repair soundness score of the segment by: a priority corresponding to the road standard of the road to be repaired, obtained based on the element information; a priority that takes into account the number of segments of the same repair type within a specified range; and a priority that takes into account the number of locations within the same route where the same type of repair is required. Then, the system calculates a discrete variable that maximizes the total sum of: a value obtained by multiplying the weighted soundness score after repair by a discrete variable taking either 1 or 0 for each segment, and a value obtained by multiplying the soundness score by the difference between 1 and the discrete variable.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a system for supporting the formulation of a road maintenance management plan using mathematical optimization.

Background Art

[0002] Various methods have been proposed to support the formulation of a maintenance management plan for a building using mathematical optimization.

[0003] For example, Japanese Patent No. 7297165 discloses a method of forming a network model by assigning a soundness evaluation value at an arbitrary point in time as a node for each structure unit and assigning a repair cost or a cost in the case of non-repair to an edge, and determining an optimal repair scenario.

[0004] In addition, Japanese Unexamined Patent Application Publication No. 2019-71017 discloses a method of determining an optimal repair time for an arbitrary repair location on a road using an autoregressive model or the like based on past deterioration conditions, repair history, traffic volume, and the like.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Disclosure of the Invention

Problems to be Solved by the Invention

[0006] However, in the conventional methods for supporting the formulation of a maintenance management plan for structures such as bridges, it has been difficult to apply them to items that comprehensively manage a wide range, such as pavement repair and weeding.

[0007] On the one hand, conventional methods for supporting the formulation of road maintenance management plans require historical information such as traffic volume, maintenance history, and damage history, and it has been difficult to apply them to roads where the historical information has not been database-ized and organized.

[0008] Therefore, an object of the present invention is to provide a road maintenance management plan formulation support system that can be applied even when historical information has not been database-ized and organized for items that comprehensively manage a wide range when formulating a road maintenance management plan using mathematical optimization.

Means for Solving the Problems

[0009] The road maintenance management plan formulation support system according to the present invention divides a road to be repaired into a plurality of segments, and uses the specifications information of the road to be repaired and the soundness score indicating the state of the road to be repaired. For each of the plurality of segments, the priority corresponding to the road specifications of the road to be repaired obtained based on the specifications information, the priority taking into account the number of segments of the same repair type within the set range, and the priority taking into account the number of locations where repairs of the same type are required within the same route are multiplied by the post-repair soundness score of the segment to calculate a post-repair weighted soundness score. The discrete variable that takes either 1 or 0 for the post-repair weighted soundness score for each segment is calculated by calculating the sum of the value obtained by multiplying the discrete variable by the post-repair weighted soundness score for each segment and the value obtained by multiplying the soundness score by the difference between 1 and the discrete variable, and maximizing the sum of these values.

[0010] The discrete variable may be calculated within a range that satisfies the condition that the total repair cost, which is the sum of the costs obtained by multiplying the discrete variable by the repair cost for each segment, is equal to or less than the budget upper limit.

[0011] The repair scheduled for each segment is classified according to the soundness score, and the sum of the small-scale implementation discrete variable that takes 1 when small-scale repair is carried out and 0 when small-scale repair is not carried out in the classification for each segment, the repair cost, and the cost obtained by multiplying the discrete variable is calculated as the small-scale repair discrete variable that is equal to or greater than the cost allocated to the small-scale repair of the total repair cost.

[0012] The repair scheduled for each segment is classified according to the soundness score, and the sum of the large-scale implementation discrete variable that takes 1 when large-scale repair is carried out and 0 when large-scale repair is not carried out in the classification for each segment, the repair cost, and the cost obtained by multiplying the discrete variable is calculated as the large-scale implementation discrete variable that is equal to or greater than the cost allocated to the large-scale repair of the total repair cost.

Advantages of the Invention

[0013] The road maintenance management plan formulation support system according to the present invention uses the specifications information of the road to be repaired and the soundness score indicating the state of the road to be repaired, so it can be applied even when the history information is not databaseized and organized. In addition, the road to be repaired is divided into a plurality of segments, and for each of the plurality of segments, the priority corresponding to the road standard of the road to be repaired obtained based on the specifications information, the priority taking into account the number of segments of the same repair type within the set range, and the priority taking into account the number of locations where the same type of repair is required within the same route are multiplied by the post-repair soundness score of the segment to calculate the post-repair weighted soundness score, so it can also be applied to items that comprehensively manage a wide range.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0015] While referring to FIG. 1, an embodiment of a road maintenance management plan formulation support system according to the present invention will be described. The road maintenance management plan formulation support system of this embodiment includes a road information storage unit 1, a soundness evaluation information storage unit 2, an optimization calculation unit 3, an output unit 4, and a soundness evaluation data storage unit 5.

[0016] In the road information storage unit 1, specifications information of the road to be repaired is stored. The specifications information is mainly information related to the design of the shape, structure, etc. of the road, and information related to the laying work. Historical information indicating the usage status after opening, such as traffic volume, is not essential but may be stored as reference information.

[0017] In the soundness evaluation information storage unit 2, for each of a plurality of segments formed by dividing the road to be repaired, the soundness evaluation score of the road to be repaired and the facilities attached to the road at the time of formulating the road maintenance management plan, and the expected soundness score after repair by performing repair are stored.

[0018] An optimization condition setting unit 6 for setting the conditions for arithmetic processing is connected to the optimization calculation unit 3. The conditions for arithmetic processing are input to the optimization condition setting unit 6 via an input unit 7, and the optimization calculation unit 3 uses the data stored in the road information storage unit 1 and the soundness evaluation information storage unit 2, and performs arithmetic processing for determining the necessity of repair for each segment according to the conditions set by the optimization condition setting unit 6.

[0019] In the arithmetic processing executed by the optimization calculation unit 3, first, for each of a plurality of segments, a priority corresponding to the road standard of the road to be repaired obtained based on the specifications information (hereinafter referred to as "road standard priority"), a priority taking into account the number of segments of the same repair type within the set range (hereinafter referred to as "proximity priority"), and a priority taking into account the number of locations requiring the same type of repair within the same route (hereinafter referred to as "route priority") are multiplied by the post-repair soundness score of the segment to calculate the post-repair weighted soundness score. The definition formula of the post-repair weighted soundness score in this embodiment is shown below.

[0020]

Equation

[0021] Next, a discrete variable that takes either 1 or 0 is multiplied by the post-repair weighted soundness score for each segment, and the sum of the value obtained by multiplying the soundness score by the difference between 1 and the discrete variable is calculated to find the discrete variable that maximizes the total sum. Then, based on the discrete variable, it is determined whether repair is necessary for each segment. That is, if the discrete variable is 1, repair is required, and if the discrete variable is 0, repair is not required. The calculation formula of the discrete variable in this embodiment is shown below.

[0022]

Equation

[0023] Also, in this embodiment, as an optimization condition, the budget upper limit is considered. The calculation formula of the discrete variable that satisfies the budget upper limit is shown below.

Equation

[0024] Furthermore, in this embodiment, according to the soundness score S, after classifying the repairs scheduled for each segment into preventive maintenance, minor repairs, and major repairs, as optimization conditions, the budget allocated to minor repairs and the budget allocated to major repairs are considered.

[0025] The calculation formula for the discrete variable of minor implementation that satisfies the budget allocated to minor repairs is shown below.

Equation

[0026] Next, the calculation formula for the discrete variable of major implementation that satisfies the budget allocated to major repairs is shown below.

Equation

[0027] The repair necessity judgment result for each segment obtained by the arithmetic processing of the optimization arithmetic processing unit 3 is output to the output unit 4 and stored in the soundness evaluation data storage unit 5. Also, for the segments determined to require repair, the soundness score after repair is substituted, and the soundness score at the time when it becomes the target of the next repair plan is estimated, and the estimated value is stored in the soundness evaluation information storage unit 2. For example, when repairs are performed annually, the estimated value one year after the repair is stored. Therefore, the calculation regarding the repair timing that comes after the repair according to the repair plan can also be continuously executed using this estimated value.

[0028] Note that the soundness score can be estimated, for example, using a deterioration curve. However, there is no restriction on the estimation method, and other known estimation methods may be adopted.

[0029] The repair necessity judgment result for each segment stored in the soundness evaluation data storage unit 5 is displayed on the display unit 8 together with the set conditions input to the optimization condition setting unit 6 via the input unit 7.

Example

[0030] Regarding a road passing through a small city in the northern part of Texas, USA, a 53.5 km long section was divided into 5348 segments (every 10 m), and for each segment, it was determined whether repair was necessary, and a pavement repair plan was formulated.

[0031] For the arithmetic processing to determine whether repair is necessary, the following were used as road information. · Pavement type: Asphalt / Concrete · Residential road width: 21 Feet · Secondary arterial road width: 24 Feet · Tertiary arterial road width: 24 Feet

[0032] The soundness was evaluated for each segment with a score from 0 to 100. Also, it was aggregated into a seven-level evaluation where 0 - 10 is the 7th level, 11 - 25 is the 6th level, 26 - 40 is the 5th level, 41 - 55 is the 4th level, 56 - 70 is the 3rd level, 71 - 85 is the 2nd level, and 86 - 100 is the 1st level, and the repair type, repair unit price, and post-repair score were set. The correlation between the soundness evaluation score, the seven-level evaluation, the repair type, the repair unit price, and the post-repair score is shown in Figure 2, and the situation of the road to be repaired shown in the seven-level evaluation is shown in Figure 3.

[0033] For calculating the post-repair weighted soundness score, weights corresponding to road specifications and with higher priorities as the numerical values increase were set as follows. · Residential road: 3 · Secondary arterial road: 1 · Tertiary arterial road: 1

[0034] Also, the range for searching segments of the same repair type for calculating the post-repair weighted soundness score was set to 150 feet.

[0035] Furthermore, as optimization conditions, the budget was set as follows. · Budget ceiling: 300,000 USD / Year · Allocation budget for minor repairs: 20% · Allocation budget for major repairs: 30%

[0036] The condition of the road to be repaired after repair according to the pavement repair plan for the first year formulated is shown in FIG. 4, and the condition of the road to be guaranteed after repair according to the pavement repair plan for the second year is shown in FIG. 5. Also, the deterioration curve used to estimate the soundness score one year after the repair of the part to be repaired in the first year (when formulating the pavement repair plan for the second year) is shown in FIG. 6. In FIGS. 4 and 5, the parts that became the first in the 7-level evaluation due to repair are not colored.

[0037] Under the optimization conditions set in this embodiment, it was confirmed that the locations where segments of the same repair type are concentrated, giving priority to residential streets, are selected as repair targets.

Description of Reference Numerals

[0038] 1 Road information storage unit 2 Soundness evaluation information storage unit 3 Optimization calculation unit 4 Output unit 5 Soundness evaluation data storage unit 6 Optimization condition setting unit 7 Input unit 8 Display unit

Claims

1. Divide the road to be repaired into a plurality of segments, Use the specifications information of the road to be repaired and the soundness score indicating the state of the road to be repaired, For each of the plurality of segments, the priority corresponding to the road standard of the road to be repaired obtained based on the specifications information, the priority taking into account the number of segments of the same repair type within the set range, and the priority taking into account the number of locations where repairs of the same type are required within the same route are multiplied by the post-repair soundness score of the segment to calculate the post-repair weighted soundness score. Calculate the discrete variable that maximizes the sum of the value obtained by multiplying the post-repair weighted soundness score for each segment by either 1 or 0 and the value obtained by multiplying the soundness score by the difference between 1 and the discrete variable, and a road maintenance management plan formulation support system characterized by this.

2. Calculate the discrete variable within the range that satisfies the condition that the total repair cost, which is the sum of the costs obtained by multiplying the repair cost for each segment by the discrete variable, is equal to or less than the budget ceiling. The road maintenance management plan formulation support system according to Claim 1.

3. The repairs scheduled for each segment are classified according to the soundness score, Calculate the small-scale implementation discrete variable that takes 1 when small-scale repairs are carried out and 0 when small-scale repairs are not carried out in the classification for each segment, and the sum of the repair cost and the cost obtained by multiplying the discrete variable is equal to or greater than the cost allocated to the small-scale repairs of the total repair cost. The road maintenance management plan formulation support system according to Claim 1.

4. The repairs scheduled for each segment are classified according to the soundness score, The large-scale implementation discrete variable that takes 1 when large-scale repair is carried out in the classification for each segment and 0 when large-scale repair is not carried out, the repair cost, and the sum of the cost obtained by multiplying the discrete variable is greater than or equal to the cost allocated to the large-scale repair of the total repair cost, and the road maintenance management plan formulation support system according to claim 1 for calculating the large-scale implementation discrete variable.

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