Ground Deformation Monitoring Technology And Its Application In Xiaolangdi Multipurpose Project

After the establishment of the P. R. China, several dozens of thousands of dam have been built. The safety monitoring of dam is a significant tool to secure the dam operation safely. Based on the data and information obtained from in-situ monitoring on settlement, inclination and deformation of engineering structure, basic information and suggestions could be provided to improve the physical properties of structures and strength index of foundation. The information and data obtained from the monitoring could be also used to analysis the landslide mechanism and predict the landslide developing tendency. The deformation monitoring provide basic data for deformation to analysis and prediction.The external deformation monitoring is a main part of engineering safety monitoring. The geodetic method, following the philosophy of assorting net and principle of progressive control has been involved design horizontal control and elevation control net to providing baseline point for dam safety monitoring and furthermore been used to monitor the stability of baseline point and rockmass in the vicinity. The external deformation measurement consist of fixed point, baseline point and monitoring net. The Xiaolangdi external deformation monitoring during the construction consist of three main parts: external deformation monitoring around the dam, external deformation monitoring for slope in the vicinity of dam, active fault monitoring and ground deformation monitoring.The paper, concerning the characteristic of engineering and geology, studied the creation of the Xiaolangdi multipurpose project safety-monitoring system. A zoned monitoring system under the control of unique baseline has been proposed. Manu possible monitoring methods, especially, the accuracy of collimation axis, intersection, olar coordinate, have been studied in detail to provide the theory foundation of the application of intelligent otal-station instrument automatic monitoring system on Xiaolangdi project.The application of intelligent otal-station instrument, TCA2003, and digital water level,DiNil2, on the dam safety monitoring as well as data automatic recording have been researched extensively. All this research provide the valuable experience to in-situ data collection, automatic transferring, data analysis and treatment and management.