Analisis Perbandingan Desain Lapis Tambah (Overlay) Perkerasan Lentur Menggunakan Metode Bina Marga 2017 dan AASHTO 1993

Studi Kasus: Ruas Jalan By-Pass Bandara Internasional Lombok – Mataram

Abstract

The continuous increase in vehicle traffic, both in terms of volume and axle load, has significantly affected the service life of national roads. One of the strategic roads in West Nusa Tenggara Province is the Lombok International Airport – Mataram By-Pass Road, which serves as the primary corridor connecting the airport, Mataram City, and the Mandalika tourism area. The traffic characteristics on this route are distinct from typical urban roads, consisting of heavy trucks, tourist buses, and private vehicles of visitors. These conditions directly contribute to the structural deterioration of the flexible pavement, as indicated by surface cracking, rutting, and reduced riding comfort. To maintain service performance, it is essential to improve the pavement’s structural capacity through overlay. This study aims to analyze and compare overlay thickness design using two approaches: the Indonesian Manual Desain Perkerasan Jalan Bina Marga 2017 and the AASHTO 1993 method. The data employed include Average Daily Traffic (ADT), Vehicle Damage Factor (VDF), and deflection data obtained from the Falling Weight Deflectometer (FWD), which were subsequently adjusted to representative values. The results indicate that the Bina Marga 2017 method yields a thinner overlay design compared to the AASHTO 1993 method. The difference arises from the distinct design approaches, where Bina Marga 2017 is mechanistic-empirical, emphasizing the Cumulative Equivalent Standard Axle (CESA) and characteristic deflection values, while AASHTO 1993 is empirical, relying on subgrade resilient modulus, pavement layer modulus, and the effective structural number (SNeff). This comparative analysis highlights that the choice of design method significantly influences overlay requirements. Considering the mixed traffic of tourism-related vehicles and the specific subgrade conditions in Lombok, the findings are expected to serve as valuable input for pavement designers in selecting efficient and context-appropriate overlay design methods.