Study of Detailed Survey of Pavement Using Large Core Bowling and Repair Design in Deteriorated Pavement Where Difficult of Open Cut Survey

Abstract

 The deterioration of pavement on national highways were confirmed in Nagano Prefecture. To identify the factors contributing to the pavement damage prior to implementing repair design, a detailed investigation was conducted primarily using large-core sampling. The results confirmed the condition of damage in the asphalt concrete layer, the coefficient of subgrade reaction on the upper subgrade, and the feasibility of sampling for laboratory tests. This method was deemed effective for elucidating the factors causing pavement damage. However, it was also found that the quantity of samples obtainable and the assessment of coefficient of subgrade reaction in the depth direction could not be conducted to the same extent as with excavation surveys. Therefore, it is deemed necessary to continue investigating similar surveys to establish a detailed investigation method centered on large-core sampling.