The evaluation and readjustment of the VPI-CE horizontal control network

Abstract

The main objective of the VPI-CE control network. is to contribute to the Nation.al Geodetic Survey control network. In order to meet this objective, large amounts of survey data were accumulated at different times from various surveys between the years 1977-1980. Bach different set of survey data was reduced and adjusted by least squares independently creating various "sub" control networks that were connected to each other peace- . meal. When "sub" control networks were connected to each other, it was found that they did not meet the objective stated above. It is the purpose of this project to examine and check all survey data, adjust all data as one set to the NGS control network, and to evaluate the adjusted data to see if the survey meets second-order class II traverse specifications as established by the NGS. Included in this paper are the following: a background on NGS specifications; least squares theory including observation equations, and error theory; a description of how data for the project was accumulated and reduced; the adjustment of the reduced survey data; results and analysis of the adjustment; and conclusions and recommendations for the survey.