Deformation Monitoring of Dam Using GPS: Case Study Letsibogo Dam, Botswana

All civil engineering structures are susceptible for deterioration over a period of time after been constructed. Dams, bridges, tunnels, high rise buildings deteriorate due to different factors such as stress, unstable slopes, low foundation shearing strength, settlement, expansion from temperature changes, and age. As a results of these effects, long and short term deformation monitoring of these structures is very important to validate the construction specifications and safety measures. Long term deformation monitoring is mainly based on measurements of horizontal and vertical movement of the entire structure to ensure that every part of the structure is stable. In this work we present the first deformation monitoring of Letsibogo dam in Botswana by establishing baseline points using Global positioning Systems (GPS) which is capable of detecting structural movement in three dimension. The results obtained shows that the established reference and monitoring points measured by using GPS are reliable with standard deviations of 0.004m and 0.007m in x and y respectively and horizontal displacement of 1cm. In addition, the correlation coefficient for the observations

Dam deformation, geodetic technique, global positioning system.