This volume, the first of a four-volume final report, presents a summary of the research conducted and procedure developed for identifying rural non-freeway geometric design inconsistencies. Volume II documents the research conducted and the study results. Volume III presents the highway geometric inconsistency procedure. A detailed on-site inventory of the geometric features studied, supporting laboratory data and a cost-effectiveness methodology are presented in Volume IV. The conceptual basis of the study is that the roads of today have created an expectancy set that cannot be ignored in design. Certain types and combinations of geometric features (e.g., divided highway transitions, lane drops, intersections and sharp curves) are not expected by drivers and, when presented in unusual circumstances, are likely to violate driver expectancy and cause unsafe driving to occur. Field and laboratory studies provided empirical data to support the results. (Author/publisher)
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