Analysis Of The Upstream Damming Flood Outburst Of Jinping First-level Hydropower Station

Jinping first-level hydropower station is the control reservoir on the Yalong River,the dam area is located in Pusiluogou Canyon section.Navigation in the development beach of the river,power plant installed capacity of 3600 MW,annual average annual power output of 16.62 billion kW · h.The upstream landslide body of Jinping first-level hydropower station is from Lenggou hydropower station in the dam site,down to the Lenggou hydropower station under the dam site.In March 2013 the first unit was operated to generate electricity.There is a danger of landslide and deformed body in the upper reach of Jinping first-stage hydropower station to form the barrier lake,and the possibility of the dam body collapse is large,that is to say,the Jinping first-class dam is facing the serious threat of the collapse mountain flood.In this paper,the landslide and the deformed body are analyzed and predicted after the landslide and the deformed body are destructed and destructed.Then the appropriate numerical simulation method is used to construct the model of the floodwater in the upstream.And the impact of the flood protection on the dam safety is analyzed.Then,the corresponding measures and suggestions are put forward to support the safe operation of the Jinping I Hydropower Station.Around the above research ideas,this paper mainly carried out the following four aspects:(1)The unstable landslide and the dam failure analysis of the deformable body are analyzed respectively from four aspects,such as the destabilization failure scale,the height of the dammed body,the stability of the dammed body and the stability time,and the analysis of the collapse of the dam body.Five main unstable bodies and landslides in the upper reach are selected and analyzed,and the accumulation patterns and failure modes of the dammed bodies are analyzed.(2)The DAMBRK model is used to construct the model of the floodwater in the upper reaches of the Jinping River,and the model is validated by the measured data.The representative dammed body is selected and the calculation scheme is calculated.The calculation of the flood-The process of the flood peak flow and the evolution of the flood in the downstream are analyzed.(3)According to the calculation result of upstream collapse weir flood,the time of dammed lake to dam height is analyzed.On the basis of this,according to the operation mode of Jinping first-class reservoir,choosing the normal water level of 1880 m,flood control Limit water level of 1859.06 m and dead water level of 1800 m,combined with the flow situation of upstream collapse mountain flood,analyze and formulate reservoir operation plan.(4)According to the calculation result of the upstream collapse weir flood,the influence of the cross-mountain flood to the dam's stress and abutment stability is calculated by taking the water level of 1889.65 m before the dam,and the influence of the flooding on the dam safety is analyzed.Measures and suggestions of engineering prevention measures.