Research On Gongboxia Hydro-power Station Construction During Flood Perind

Combined with the significant project-Gongboxia hydro-power station construction, emphasized on construction during flood period of power station construction period, the climate character of the upstream of Yellow river basin and the practice operation state of cascade reservoirs are analyzed, some problems in construction during flood period such as flood propagation time, interval flood discharge forecast, construction risk, flood period pre-alarm and Longyangxia reservoir's function on construction of Gongboxia are also studied, with an aim at presenting real interval flood forecast scheme and dispatching method, so as to provide technological support for Gongboxia hydro-power station construction period. The main results of the paper are as follows:(1) Research on flood propagation time. The prediction period of flood forecast is decided by the flood propagation time to a great extent, and its shorter or longer play an important role in decision of construction scheme during flood period. Based on analyzing discharge data in Guide, Xunhua, Tongren hydrologic station and river course character, propagation time of different discharge in different river course is presented, and prediction period of interval flood, main stream flood during construction and operation period are acquired.(2) Research on forecast model and real-time correction methods. Geography position and meteorology character in Gongboxia watershed are analyzed, according to which the excess of infiltration and instantaneous unit hydrograph are used in runoff and affluence models, and Muskingum routing method in river course affluence, Kalman filtering technique and least square method in real-time correction.(3) Research on construction scheme during floof period. By analyzing interval flood and cascade operation characteristics of the upstream Yellow river basin, the influence of Longyangxia reservoir operation mode in different states on Gongboxia power station construction during flood period is studied. Through studying Longyangxia reservoir reasonable operation mode , Gongboxia hydro-power station's flood period scheme and improvement flood period standard scheme are established in this paper.(4) Research on the risk . On base of analysis of the main factors of construction risk, interval flood character, operation mode of Longyangxia and Gongboxia reservoirs, the risk of Longyangxia reservoir in different operation mode is estimated.(5) Research on pre-alarm mode. The main buildings of resisting flood such as cofferdam and diversion tunnel without the capacity of flood control play a role in flood detention. By studying on different operation mode and different interval flood of Longyangxia reservoir, as well as the flood propagation time, pre-alarm scheme is established, which can alarm in order to lower construction losses when flood is in excess of standard.