COMPARISON OF DIFFERENT MERCATOR PROJECTION SYSTEMS FOR THE TOPOGRAPHICAL SURVEY OF THE BUCHANAN-TOKADEH (YEKEPA) RAILWAY, LIBERIA, AFRICA

Ibarra Granda J.A.; SOARES DA SILVA E. · Geodesy and Cartography (Vilnius) (2025) · DOI: 10.3846/gac.2025.21650

Resumen

For this project of the Buchanan-Tokadeh (Yekepa) railway located in the Republic of Liberia, Af-rica, it is about carrying out comparative analysis of precisions between two projection systems, the Local Transverse Mercator (LTM), divided into 15 zones; and Hotine Oblique Mercator (HOM); as well as the projection heights of their Local Topographic Planes (LTP) both in orthometric heights to determine the scale factor, as well as ellipsoidal ones to extend the semi-axes of the ellipsoid of the WGS84 datum to give an scale factor equal to 1 of these systems, along 245 km of route, taking as reference tolerances precisions that must be within 1/40,000 or 2.5 cms per kilometer, and also that the difference in height does not ex-ceed 150 meters. Getting results by performing survey traverse polygon made with a total station, in a way that the deformations using an LTM divided into 15 zones and the HOM expanding the semi-axes of the reference ellipsoid of the Datum WGS84 complying with the aforementioned standards.

Instituciones: Universidad Nacional Mayor de San Marcos