Capacity analysis for two way stop controlled (TWSC) intersections is mainly based on headway acceptance theory. Critical headways and follow up times are fundamental parameters in capacity estimation. Both factors clearly show the influence of driver behaviour on traffic operations. The critical headway parameter is typically associated with safety and
operational performance of this intersection type.
This paper explores critical headways and follow up times by analyzing data from video recorded tapes collected in urban intersections located in the city of Cordoba, Argentina in order to derive local values that can be used in capacity estimates at unsignalized intersections. Maximum likelihood methodology and regression analysis are employed. An
exponential model is then used to assess the relationships between headways and capacity.
Estimates for both headways are significantly smaller than the values given in version 2010 of the Highway Capacity Manual. Increased capacity, due to critical headway and follow up time reductions, becomes proportionally greater as conflicting flows grow. Percent differences increase while curves tend to get closer. From this point of view the conclusion is
that intersections operate more efficiently, but also more dangerously.Fil: Depiante, Violeta S. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Maestría en Ciencias de la Ingeniería. Mención en Transporte; Argentina.Fil: Galarraga, Jorge J. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Maestría en Ciencias de la Ingeniería. Mención en Transporte; Argentina.Ingeniería del Transport
