Abstract:
Due to limited availability of vehicle load data, estimator often use standard load in order to
calculate the pavement thickness and overlay course thickness. This certainly makes the
calculation of pavement thickness and overlay course thickness become not accurate. Inaccurate
calculation results less capability of the pavement to endure the traffic load, as of the pavement
become damaged before it reach it life service as planned. The aim of this study is to calculate
overlay course thickness of flexible pavement based on actual load, standard load and remaining
life service. The standard load that has been used based on form letter (Surat Edaran) Directorate
General of Perhubungan Darat, Department of Public Works No. 2, 2008. The actual load was
obtained by vehicle load survey using Portable Weighter instrument. Overlay course thickness
was calculated using Manual Design of Pavement No. 02/M/BM/2013. The study case was
conducted on four road segments, those are Tanah Badantung – Kiliran Jao road, Batas Kota
Padang – Kota Painan road, Batas Provinsi Riau – Payakumbuh road and Sicincin – Lubuk
Alung road. The traffic load estimation shows that the actual traffic load is greater than standard
load. This results the overlay course thickness based on actual load is greater than the overlay
course thickness based on the standard load. The greater distinction is on Tanah Badantung –
Kiliran Jao load, wherein the thickness of overlay course that results by actual load is 56.4%
greater than the thickness of overlay course that results by standard load. The greater traffic load
also results reduction on pavement life service. Due to overloading, life service of Tanah
Badantung - Kiliran Jao road is reduces 56.8 % of 5 years life service (2 years and 10 months).
Kata kunci: Overlay, Overload Vehicle, Remaining Life.
