Experience of Using Total Station and GNSS Technologies for Tall Building Construction Monitoring

摘要

In prevalent engineering practice, geodetic measurement techniques are commonly applied for structural monitoring. For a long time, triangulation, trilateration and levelling techniques have been trusted for the determination of structural deformation and point displacement, with excellent outcomes. With the advent of robotic total stations, the three-dimensional topographic measurement method has been proposed as an efficient and rapid measurement option for the determination of 3D coordinates. In addition, the GNSS (Global Navigation Satellite System) technology improvements, mainly in the RTK (Real-Time Kinematic) measurement mode, opened a new perspective for monitoring, which has also shown consistent results. However, there are some situations where the use of total station or GNSS technology individually is not enough to perform the monitoring. The solution may then be the combination of both technologies. In this paper, we present the details of two proposed measurement methods and the results of a testing campaign carried out to monitor the construction of "La Costanera Tower", in Santiago, Chile, using a total station combined with GNSS receivers. These methods are based on the use of GNSS antennas and total station installed on the under-construction building floor. Having this scenario, two measurement procedures were applied. The first one was based on using a total station coupled with a GNSS receiver, for determining the position of the monitoring point and a GNSS antenna coupled with prism reflector, for the orientation of the total station. The second procedure was based on using a total station and two GNSS antennas coupled with prism reflectors. With this equipment, directions and distances were measured, to determine the position and orientation of the total station, by means of a Free Station positioning computation. The testing results have been compared with traditional measurement techniques. The results showed that the proposed methods could be a suitable solution for monitoring tall building construction.