This paper presents the results of a research on the capacity determination in selected basic segments of North and South Luzon Expressways. This study focuses on the establishment of a speed flow curve. This study also includes lane utilization analysis of the considered segments and a macroscopic approach in the estimation of passenger car equivalent for trucks. The speed-density relationship obrtained from the data taken from the South Luzon Expressway is linear in nature, which is similar to other countries. The lane utilization indicated a 70-30 percentage share of traffic for the inner and outer lanes, respectively, in the segment of North Luzon Expressway. In the South Luzon Expressway segment, lane utilization is equal. The passenger car equivalent for truct obtained in this study is 2.7.
