Vehicle damage factor (vdf) analysis on freight transport vehicles :: Case study on Jogya-Prambanan Highway

JIHAD, Shaiful, Ir. Djoko Murwomo, M.Sc

2009 | Tesis | S2 Magister Sistem dan Teknik Transportasi

An accurate estimation of the current traffic load is essential for an appropriate pavement design, because pavement thickness and durability depend on the carrying loads. The accurate estimation of vehicle loads can only be obtained by an axle load survey. Overload on the traffic often considered as the main factor that shortens pavement life time. The information about axle loads is required so that accurate forecast can be made. A methodology is outlined using traffic volume, vehicle type and axle load data to estimate the VDF value. Data from a weight bridge have been collected and analyzed. The weight bridge unit, which comprises weigh pads and two unit digital weighing indicator, were available on Jl. Jogja-Prambanan sta 700. The data were collected continuously for 2 x 24 hours since 20th to 22nd October 2008 for each commercial vehicle and include axle loads, number of axle, tire configuration, vehicle type and vehicle direction. The weigh pads measure each axle loads and then digital weighing indicator shows axle loads value. Hourly traffic volumes were counted manually. Some preliminary data analysis including vehicle classification and direction were done on site by the surveyor. Further data analysis used Excel spreadsheet computer program to calculate equivalent single axle loads (ESALs), vehicle damage factor (VDF) and traffic analysis period. Beside real axle loads data which were obtained on the surveys, standard axle load limit and The Binamarga default VDF were used as a comparison. The result of this study was the real VDF value for Jogja-Prambanan highway. Traffic composition was dominated by 95 percent of passenger cars and light buses. The composition of commercial vehicle was 5 percent from the total traffic volume. The differences of traffic analysis period resulted from real axle loads and The Binamarga default VDF as 21.46 percent were also gained. This was caused by different assumptions on the vehicle types and axle load, especially on 60 passenger heavy buses. Overloading problem resulted in 11.65 percent differences in traffic analysis period. Those results may be used as a consideration to improve the default VDF, design and analysis of pavement structures as well as the law enforcement.

Kata Kunci : Axle load,Vehicle damage factor,Eguinvalent single axle load and traffic analysis period