Abstract:
The micro-amplitude deformations of concrete face rockfill dams (CFRDs) can last for a very long time due to creep effect and external influences. The seepage control system such as the concrete face can be damaged if these micro-amplitude deformations continue to grow. Traditional deformation measuring methods are suffering from low accuracy and low frequency, thus the data can hardly reflect the true deformation features of CFRDs. To improve this defect, the Hydrostatic Level System and the Tension Wire Alignment System are applied for measuring the vertical and horizontal surface deformations for Zeya Reservoir dam. After a 5-year continuous monitoring, the monitoring data reveals that: ①The above measuring system can meet the requirements of the long-term and micro-amplitude deformation monitoring. ②The deformaions due to material creep have not stopped even after 20 years, the max average vertial deformation and horizontal deformaion rate can reach 4.33 mm/a and 3.50 mm/a, respectively. ③The deformation rates are reducing gradually, thus the deformations tend to converge. The above findings can provide useful references for monitoring system design and creep behavior studying.