Journal of the Korean Asphalt Institute ISSN:2234-0785(Print) 2635-9553(Online) 한국아스팔트학회지

This study aims to evaluate and compare the economic feasibility of the lean concrete method (LCM) and the gravel wearing course (GWC) method for unpaved road improvement in Laos. The analysis incorporates the estimation of construction costs per cubic meter, projection of future inflation rates based on a 10-year review of the Consumer Price Index (CPI) and inflation data, and scenario-based assessments using three economic conditions: optimistic, neutral, and pessimistic. The results show that although the lean concrete method has a higher initial construction cost, its long service life of approximately 25 years leads to significantly lower long-term financial burden. In contrast, the GWC method requires annual reconstruction due to a one-year service life, causing cumulative construction costs to rise rapidly. Across all scenarios, the cumulative cost of the GWC method exceeded the initial lean concrete cost within 2-5 years, with the crossover occurring earlier under the pessimistic scenario. By 2050, cumulative GWC costs reached approximately 0.66 million USD, 0.96 million USD, and 2.47 million USD under the optimistic, neutral, and pessimistic scenarios, respectively, demonstrating a substantially higher long-term expenditure compared with lean concrete. The findings highlight the importance of life-cycle cost considerations rather than initial unit cost in selecting construction methods for rural roads in developing countries such as Laos.