Challenges in Managing Road Facilities
Road facility management is one of the core responsibilities of local governments, facing several issues such as aging infrastructure, budget shortages, and the absence of an efficient maintenance system. In particular, the deterioration of road facilities increases the likelihood of safety accidents, leading to gradually increasing costs for reactive maintenance. In this situation, local governments need a systematic and strategic approach for preventive maintenance of road facilities, but the current budget operation methods and management systems do not effectively support this.
Budget Shortages and Inefficient Allocation
- Local governments have limited budgets for infrastructure maintenance, and there are difficulties in efficiently allocating funds to necessary items.
- The budget allocation process requires cooperation between the government and local authorities, but currently, it is uniformly allocated by the central government.
Complexity and Diversity of Road Facilities
- Road facilities consist of various elements such as structures, pavements, and drainage systems, leading to high complexity in the maintenance process.
- Each facility has unique characteristics and purposes, resulting in different maintenance cycles and methods. Simple budget allocation that does not reflect these differences can reduce management efficiency and lead to greater long-term costs.
Lack of Field-Based Data
- There is a lack of reliable data that can accurately diagnose the condition of road facilities. This is a major factor in reducing the accuracy and efficiency of maintenance strategy development.
- In particular, there is insufficient quantitative data necessary for facility management, making it difficult to take a scientific and systematic approach to preventive maintenance.
The Need for preventive Maintenance of Road Pavements
Road pavement is a critical element directly related to traffic safety. Through preventive maintenance, both cost reduction and safety enhancement can be achieved simultaneously, as opposed to reactive maintenance.
Severity of Aging and Problems
- According to research by the Korea Expressway Corporation and Seoul City, road pavement deterioration progresses rapidly on roads over 10 years old, and if left unattended, maintenance costs increase exponentially.
- The degradation of road pavement is closely related to traffic accident rates, making preventive management essential for prevention. preventive maintenance can ensure long-term safety and economic efficiency.
Cost-Effectiveness
- preventive maintenance is cost-effective in the long term compared to reactive repairs. For example, research shows that performing maintenance at a minor deterioration stage can save 30-50% compared to restoration costs after progressing to severe deterioration.
- Life cycle cost analysis results show that preventive maintenance effectively extends the lifespan of road pavements and delays repaving cycles, significantly reducing the total maintenance costs.
Improved Road Safety
- Preventive maintenance plays a crucial role in ensuring vehicle driving safety, which directly leads to a reduction in traffic accidents. The better the road condition, the more effectively accident risks can be reduced.
- Additionally, good road conditions provide the added environmental benefit of improving vehicle fuel efficiency and reducing carbon emissions. This means achieving both economic cost savings and environmental protection simultaneously.
- Improvement Measures for Integrated Management System for preventive Maintenance of Road Pavements
Development of Road Pavement Aging Prediction Model
- This study proposes an economic evaluation framework for flexible road networks, considering the benefits of preventive maintenance based on various factors such as the types of preventive maintenance methods, the scope of preventive maintenance compared to reactive maintenance methods, service management standards set by local governments, budget constraints, and intervention timing.
- A road pavement aging prediction model was developed that can estimate costs and conditions at the road unit level using deterioration curves based on the International Roughness Index (IRI).
Development of Life Cycle Cost Analysis Method
- The IRI-based deterioration curve is the foundation of this research, used to predict road pavement conditions based on inspection data and implementation of preventive maintenance strategies. The exponential curve has been shown in many previous studies to effectively represent road deterioration, and this study developed a road deterioration model based on the IRI.
- To answer the research question "What benefits can be expected from preventive maintenance in road maintenance?", this study investigated the long-term effects of preventive maintenance in road maintenance considering various scenarios including the ratio of reactive to preventive maintenance, types of preventive maintenance, and required serviceability for up to 50 years.
- An economic evaluation framework was proposed by separately modeling the deterioration curves for roads with and without preventive maintenance strategies.
- In the case study of the "Second Jayuro" expressway used in this study, sensitivity analysis was performed on the coverage of preventive maintenance to predict annual and total road maintenance costs.
- The simulation results of road maintenance costs over 50 years confirmed the expected costs of the expressway depending on whether preventive maintenance was implemented or not.
Proposal for Integrated Management System
- Based on these research results, this study proposed a web-based integrated management system for preventive maintenance of road pavements.
- This system starts by uploading the International Roughness Index for the relevant year and allows for adjustment of information such as the minimum road pavement standards assumed in this study, the type of preventive maintenance method to be applied, cost units, and the period to be simulated. This enables simultaneous confirmation of the costs required for preventive maintenance of road pavements under various conditions, the cost-saving effects due to preventive maintenance, and the condition of the pavement surface of the managed roads.
Analysis of preventive Maintenance Effects
- When applying a preventive maintenance strategy to road pavement maintenance, significant cost savings of up to 29.7% can be expected depending on the type of preventive maintenance work. This saving effect is mainly attributed to the reduction in the number of road units exceeding the minimum service requirements.
- The implementation scope of preventive maintenance affects cost savings, with savings ranging from 6.9% to 23.9% for preventive maintenance type 1 (slurry sealing) and from 9.5% to 29.7% for preventive maintenance type 2 (micro-surfacing). Additionally, the road repaving cycle is extended as the application scope of preventive maintenance increases.
- The cost-saving effect may vary over specific periods even when applying a preventive maintenance strategy, as the average IRI of road units follows a periodic pattern.
- As the application scope of preventive maintenance is gradually expanded from 0%, the average annual IRI value of road units requiring repair increases, indicating a slight deterioration in the maintenance road condition. This is because the preventive maintenance strategy extends the service life of road units, allowing them to be maintained at higher IRI values closer to the unacceptable serviceability level (IRIthr) for longer.
- An increase in the unacceptable serviceability level (IRIthr) value can lead to greater fluctuations in the average IRI value, affecting the cost-saving effect of preventive maintenance.
- The results of this study emphasize the potential for cost savings through the implementation of preventive maintenance strategies in road pavement management, particularly showing very distinct differences from a long-term perspective.
- While the degree of cost savings due to the implementation of preventive maintenance strategies may vary depending on the period, cost-saving effects are generally confirmed after about 10 years of introduction, with distinct decreases observed at 30-year and 50-year intervals.
- These research results are expected to promote the implementation of preventive maintenance strategies that can significantly reduce long-term road maintenance budgets by presenting cost reduction simulation results that road maintenance agencies or local governments can expect when introducing preventive maintenance strategies for road maintenance, avoiding misunderstandings about benefits due to short-term analysis.
- In particular, this study provided a basis for road facility management agencies, such as local governments, to regularly establish and revise short-term (2-3 years), medium-term (5-7 years), and long-term (10-15 years) plans annually based on these expected cost simulation results when setting road maintenance budget allocations.
Conclusion
To address the challenges in managing road facilities and effectively perform preventive maintenance of road pavements, the development and improvement of an integrated management system are essential. This can simultaneously achieve efficient budget use, improved safety, and long-term cost savings. Local governments and the central government should strengthen cooperation to support the implementation of such integrated management systems and establish technical and institutional foundations.