Stability Assessment of the Excavated Rock Slope at the Dagangshan Hydropower Station in China Based on Microseismic Monitoring

Abstract

A high-resolution microseismic (MS) monitoring system was implemented at the right bank slope of the Dagangshan hydropower station in May 2010 to analyse the slope stability subjected to continuous excavation. e MS monitoring system could real-time capture a large number of seismic events occurring inside the rock slope. e identification and delineation of rock mass damage subject to excavation and consolidation grouting can be conducted based on the analysis of tempospatial distribution of MS events. However, how to qualitatively evaluate the stability of the rock slope by utilizing these MS data remains challenging. A damage model based on MS data was proposed to analyse the rock mass damage, and a 3D finite element method model of the rock slope was also established. e deteriorated mechanical parameters of rock mass were determined according to the model elements considering the effect of MS damage. With this method, we can explore the effect of MS activities, which are caused by rock mass damage subjected to excavation and strength degradation to the dynamic instability of the slope. When the MS damage effect was taken into account, the safety factor of the rock slope was reduced by 0.18 compared to the original rock slope model without considering the effect. e simulated results show that MS activities, which are subjected to excavation unloading, have only a limited effect on the stability of the right bank slope. e proposed method is proven to be a better approach for the dynamical assessment of rock slope stability and will provide valuable references for other similar rock slopes.

Research on Temperature Control Index for High Concrete Dams Based on Information Entropy and Cloud Model from the View of Spatial Field

“…In situ observation and risk assessment are essential for making informed decisions about the construction safety of high concrete dams, with the ultimate goal of protecting both people and property [13]. If robust and reliable real-time safety monitoring strategies are conducted, then most hidden dangers can be found and catastrophic accidents can be avoided [14][15][16]. safety of high concrete dams, with the ultimate goal of protecting both people and property [13].…”

“…safety of high concrete dams, with the ultimate goal of protecting both people and property [13]. If robust and reliable real-time safety monitoring strategies are conducted, then most hidden dangers can be found and catastrophic accidents can be avoided [14][15][16]. Concrete temperature is an important in situ observation indicator for concrete dams [17][18][19].…”

Analysis of Re-Tensioning Time of Anchor Cable Based on New Prestress Loss Model

“…During the construction of highways and railways, slope excavation will not only change the original stress state of a slope, but also accelerate the weathering speed of new exposed rock mass [1][2][3][4]; therefore, it is necessary to support the excavated slope along the road to improve the stability of the excavated slope, so as to ensure the operation safety of the road. There are many kinds of slope support methods, commonly used slope support structures include retaining wall [5][6][7], anti-slide pile [8,9], prestressed anchor rod [10,11] and prestressed anchor cable [12,13], among them, the prestressed anchor cable has been widely used in slope support engineering due to its advantages of reliable strength, simple construction and economic benefits.…”

Numerical Analysis and Deformation Mechanism Study on an Excavated High-Steep Slope of a Hydropower Station

“…Based on the slope around the flood discharge tunnel at Yangqu Hydropower Station, a complicated three-dimensional (3D) numerical simulation and safety assessment were implemented in FLAC3D, while 3D slide arcs of good shape were obtained [26]. Taking the right bank slope in Dagangshan Hydropower Station in Sichuan province of China as the research background, the FLAC3D numerical simulation method was utilized to analyze its stability [27][28][29].…”