Avaliação de medidas de desempenho para rodovias de pista simples obtidas a partir de relações fluxo-velocidade

Abstract

The Highway Capacity Manual 2010 uses Percent-Time-Spent Following (PTSF) and Average Travel Speed to estimate level of service on two-lane rural highways. As it is almost impossible to observe PTSF directly in the field, many researchers have been searching for alternative measures of effectiveness (MDs) that can be obtained from traffic stream parameters. Moreover, speed-flow relationships have a fundamental role in LOS estimation in the HCM2010 and in the German HBS2001. The objective of this paper was to assess MDs derived from speed-flow relationships that could ade-quately describe quality of service on two-lane rural highways in Brazil. Speed-flow models were fitted for different condi-tions (geometry, percentages of heavy vehicles and free-flow speeds), using synthetic traffic data produced by a recalibrated version of CORSIM. Comparisons between the values obtained using these models and field data indicated that average travel speed of cars and density for cars could replace the current HCM criteria for the estimation of LOS on two-lane rural highways in Brazil.