High Slope Treatment of Xiyu Conglomerate in A Reservoir Engineering
CHANG Denglun;HAN Shoudu;Xinjiang Water Conservancy and Hydropower Investigation and Design Insitute;
Xiyu conglomerate distributed in the foothills of Tianshan Mountain and Kunlun Mountain,because of late diagenetic age and low intensity,easy to soften and disintegration under the influence of water and anti-erosion ability is poor. Within the territory of Xinjiang Bazhou a reservoir dam site area is the outdoor layer with Quaternary Xiyu conglomerate and Tertiary mudstone interlayer. Bank slope gradient is 75°-87° and slope height is 84 m at joint inlet leading edge of spillway tunnel,power generation water diversion tunnel and the diversion and water flushing tunnel. Such high and steep slope if handled improperly,under the reservoir water scour collapse and bank reengineering will happen,serious will endanger the safety engineering. According to the actual engineering,it took"cutting slope at the top for reducing load,piling up material at the slope toe for weights,concrete replacing mudstone layer at the middle part and shotcrete at overall slope surface for protection"as high slope comprehensive treatment method. Based on the 2D limit equilibrium method and 3D numerical calculation method,the stability of the intake slope of various working conditions of different sliding mode was analyzed and evaluated,so verified the rationality of the design. At the same time,by calculating the high slope stability of the mudstone interbed of Xiyu conglomerate layer,using the concrete plug,concrete beam displacement and closed treatment to avoid mudstone interbed's influence to the overall slope stability.