IWeaving Analysis for Curved Freeway Segments

F the past 20 years weaving segments have been analyzed and designed using the methodologies and procedures provided in the 1965 Highway Capacity Manual (HCM).’ With the increase in urban growth in the mid-1960s, it was quickly realized that the procedures provided in the 1965 HCM for the analysis and design of weaving segments were in need of a critical review. In 1969 the National Cooperative Highway Research Program (NCHRP) authorized a project to produce such a review. The objectives of this project were to analyze and to evaluate the weaving area procedures presented in the manual and to develop and to implement a program that would lead to improved techniques for the analysis and design of weaving segments. The final report’ for this NCHRP project was published in 1975 and served as the main source for the procedures developed for the analysis and design of weaving segmkmts in the 1985 HCM.3 The analysis conducted in this study was based on the new procedures presented in the 1985 HCM. The objective of this study was to locate and to analyze weaving segments on a major freeway in the City of Charlotte, North Carolina, using the procedures provided in the 1985 HCM. The weaving segments selected for analysis were two adjacent segments located on the Brookshire Freeway. The sites selected were valid weaving segments as defined in the 1985 HCM, including the minimum length of each weaving segment and the configuration of lanes within each segment. A distinguishing feature of the segments was that they exhibited horizontal curvature.