TY - JFULL AU - Said M. Easa and Shinya Kikuchi PY - 2009/10/ TI - Generalized Method for Estimating Best-Fit Vertical Alignments for Profile Data T2 - International Journal of Civil and Environmental Engineering SP - 307 EP - 316 VL - 3 SN - 1307-6892 UR - https://publications.waset.org/pdf/4572 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 33, 2009 N2 - When the profile information of an existing road is missing or not up-to-date and the parameters of the vertical alignment are needed for engineering analysis, the engineer has to recreate the geometric design features of the road alignment using collected profile data. The profile data may be collected using traditional surveying methods, global positioning systems, or digital imagery. This paper develops a method that estimates the parameters of the geometric features that best characterize the existing vertical alignments in terms of tangents and the expressions of the curve, that may be symmetrical, asymmetrical, reverse, and complex vertical curves. The method is implemented using an Excel-based optimization method that minimizes the differences between the observed profile and the profiles estimated from the equations of the vertical curve. The method uses a 'wireframe' representation of the profile that makes the proposed method applicable to all types of vertical curves. A secondary contribution of this paper is to introduce the properties of the equal-arc asymmetrical curve that has been recently developed in the highway geometric design field. ER -