Mechanism And Instrumentation Of Real-time Earth-rock Dam Compaction Quality Inspecting

Effective control of dam compaction quality is critical to ensure dam safety. The conventional quality control method of earth-rock dam construction is mainly based on test pits sampling. This method is difficult to meet the demands of high intensity and high mechanization of large-scale dam construction because of man-made interference and extensive management. In this paper, real-time compaction quality monitoring mechanism of earth-rock dam is deeply studied, and a real-time, continuous, automatic monitoring device of dam material compaction quality is developed finally. Then, the rolling process quality of earth-rock dam can be on-line monitored to effectively avoid under voltage and over voltage, which is significant to achieve fine management of earth-rock dam construction quality and ensure and improve the quality of dam construction. The main contents and results of this paper are as follows:(1) Real-time compaction quality monitoring mechanism of earth-rock dam is studied, mainly including the following content: the theoretical framework of intelligent compaction of earth-rock dam, real-time characterization mechanism of dam material compaction quality, and the definition and algorithms of real-time compaction quality characterization indicator based on spectral analysis of vibration acceleration. These not only provide a direct characterization indicator for compaction quality, but also supply a theoretical basis for the development of real-time monitoring device of dam material compaction quality.(2) Combined with the current research status, a real-time compaction quality monitoring device of earth-rock dam material is developed. Then, the characterization indicator CV (Compaction Value) can be obtained to real-time reflect the effect of dam material compaction. Meanwhile, CV value can be real-time displayed on LCD screen of the monitoring device, to achieve real-time, continuous and intelligent monitoring of dam material compaction quality. In addition, compaction value CV, vibration frequency and spectrum analysis data can be stored for further analysis.(3) With under construction earth-rock dam project, the field trial is conducted in the purpose of verifying the correlation between compaction value CV (CV₁,CV₂,CV₃,CV₄) defined by different formulas and dam material compaction (or dry density) obtained by test pits. The conclusion is that CV₂ shows well correlation with dam material compaction (or dry density) in the above four kinds of compaction value CV. That means CV₂ can be used as an intelligent real-time characterization indictor of dam material compaction quality, which provides a new way to judge the compaction quality of earth-rock dam.