# Airport pavement Maintenance Decision-Making System with Condition Cases Optimization
## 1 Introduction  
The aviation industry has witnessed remarkable growth, leading to an increasing demand for airport facilities and services. As airports expand and operate under higher traffic volumes, the importance of effective maintenance management becomes more pronounced. Meeting the demands of various stakeholders while optimizing resource allocation presents a complex challenge. Previous research has mainly concentrated on advancing optimization models, often overlooking their applicability in real-world scenarios. The primary objective of the airport pavement maintenance decision-making system is to efficiently maintain or improve pavement conditions within a limited budget. This not only ensures user safety but also extends the overall lifespan of the pavement, resulting in cost savings. Airport management entities strive to establish effective maintenance strategies to balance short-term requirements and long-term sustainability. The Federal Aviation Administration (FAA) provides guidance for individual airport management entities to develop their pavement management systems [1], with most management organizations applying FAA guidelines as the basis for their procedures. Korea Airports Corporation maintains and manages the pavements of 15 domestic and international airports in the country. Maintenance methods and time are determined based on functional factors such as pavement surface distress, skid resistance, and longitudinal profile. Additionally, structural stability assessments are conducted to determine remaining life of the pavement and allowable loads for aircraft. However, a challenge arises from the separation of functional and structural assessments within the decision-making process, as well as the absence of evaluation indices reflecting each country's environmental conditions. The pavement condition index (PCI), widely used in most countries, has limitations in explaining structural damage phenomena, such as blow-ups, which have been a concern in Korean pavements over the past decade. Furthermore, the estimation of remaining service life is based on \"the past damage\" concept, which is the ratio of accumulated traffic volume to the allowable load repetitions, leading to limitations in determining maintenance methods based on functional assessment and timing based on structural evaluation. When the structural remaining lifespan is less than 5 years (Level I), immediate maintenance is deemed necessary, and for cases between 5 and 10 years (Level II), continuous monitoring and maintenance planning are required. For cases exceeding 10 years (Level III), a long-term maintenance plan is established. In this process, a comprehensive assessment is performed based on functional evaluation factors, including visual inspections and lab tests, to justify the maintenance plan. It is observed that the emphasis is more on qualitative and subjective judgments rather than consistent linkage between pavement condition, predicted performance, and budget conditions at the assessment stage. It is essential to recognize that the challenges faced in Korean airport pavement management are not unique to this context. Budget allocation issues are closely linked to national policies, and implementing maintenance based solely on optimization analysis results is difficult to accept practically. Additionally, the nature of public servant systems, which tend to maintain existing regulations and practices, makes it challenging to create an environment where the effectiveness of budget allocation can be clearly evaluated relative to the budget invested. From a technical perspective, improvements are also necessary. Decision-making systems must compare costs and associated effects for each maintenance method, which can be challenging due to the difficulty of quantifying environmental factors, traffic closure times, user satisfaction, and other non-monetary elements consistently. Despite the academic advancements in optimization technology, practical airport pavement management systems have not progressed significantly.