HOW PASSING CARS AFFECT THE CAPACITY OF TWO-LANE ROADS

Two-lane highways are the most predominant systems worldwide. They make up approximately 85% of Latin America's road network which carries 76% of its traffic. A large proportion of this traffic volume consists of heavy vehicles and 45% of the roads are built on mountain or rough terrain. Parameters, such as the percentage delay time or average travel speed, set out in widely-used TRB-1994 Highway Capacity Manual do not correspond to conditions in Latin American countries and do not take into account other elements such as passing and distance which affect the capacity of this type of highway. The paper explains the differences between the HCM and actual conditions, it will also establish the effect of maneuvers and two-lane highway capacity.