Comparative Analysis of DGPS and Total Station Accuracies for Static Deformation Monitoring Of Engineering Structures
Edition: No
Series: Yes
Publisher: IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT)
Published: 2018
Place of publication: India
Copyright date: Yes
Other titles: No
Description: The displacements of engineering structures have been investigated by different researchers using one of the various geodetic methods such as GPS, Total Station, Levelling, InSAR, Photogrammetry, Theodolite, EDM and 3D Laser but in that, the accuracy of these methods have not really been compared to determine which of the methods is better in terms of accuracy, magnitude and direction of the expected deformation. This study monitored and modelled the deformation of Palm House in Benin City using GPS and Total Station and compared the accuracy of the two horizontal methods. Four reference stations and two sets of monitoring points were used. The DGPS observations were used to determine the roof monitoring points rectangular coordinates while the total station was used to determine the 10th floor base monitoring points rectangular coordinates and their bearings and distances from the reference stations. The observations were carried out at six epochs of three months interval and adjusted using least squares adjustment technique to determine the reliability of the adjusted observations and that of the adjusted parameters. The displacements magnitudes of the two sets of observations were computed using the coordinates differences between the first and the subsequent epochs observations. The evaluated displacements magnitudes were compared with their corresponding computed 95% confidence ellipses to determine the significance level. The results showed that neither the 10th floor nor the entire building underwent any movement during the monitoring period of eighteen months. The results of comparison using their a posteriori standard errors and traces of the variance co-variance matrices to determine which of them is better in terms of accuracy showed that the DGPS method is better. It was recommended that whenever more suitable and accurate method of monitoring of engineering structures that DGPS method should be selected.