Failure mechanism of deformation and evaluation of treatment effect of high slope at right bank of Luozha RiverⅡHydropower Station

In 2013, the excavation of the arch abutment of dam of Luozha River II Hydropower Station caused many hidden safety hazards such as local landslide accidents and wider loosening of the high slope at the right bank, which needed to be treated.In view of the commonality of such problems and the characteristics of this slope, the scheme of "locking feet" by prestressed anchor cable, "protection" by soil nailing+hanging net sprayed concrete, and "pressure reduction" by built-in soft drainage pipe is used to reinforce the slope.After daily inspections and the monitoring of slope displacement, groundwater level and stresses on anchor cables, the comprehensive analysis and verification of the rationality and effectiveness of the antiseepage treatment are given, and the management and maintenance recommendations are also put forward.The slope treatment was completed in 2014.It had been affected by the earthquakes of magnitude 6 or above three times in the past five years, and experienced heavy rains on July 18, 2018.It has been running well so far, which has certain guiding significance for the treatment of similar slopes.