Research On Quantitative Model For Risk Assessment Of Earth-Dammed Reservoir Staged Operation In Flood Season

In order to explore the optimal limited water level scheme for reservoir staged operation in flood season, this thesis established quantitative assessment model for flood risk of earth-dammed reservoir staged operation in flood season based on risk degree theory. The model assessed risk of the flood season staging in different limited water level for chengbihe reservoir which is the largest earth-dammed reservoir in guangxi province, and determine the optimal limited water level schemes without overproof flood risk. The result can provide some basis for the dangerous reservoir risk ranking and implementation of reservoir flood resources utilization.First, the thesis established model for overtopping risk of earth-dammed reservoir staged operation in flood season based on Monte Carlo method, and calculated the whole flood combination overtopping risk by the law of total probability. The overtopping danger degree function and gradation criteria were depended on the range of overtopping risk. Exemplification indicates that if the overtopping danger degree of chengbihe reservoir under moderate, the limited water level in each season can be established as:185.00 meters for the per-flood season and major season,185.00 meters～187.50 meters for post-flood season.Second, the thesis summarized the calculation method of the loss (including the loss of life, economic, society and environment) of earth-dammed reservoir break and established vulnerability model of earth-dammed reservoir based on the theory of the comprehensive assessment. The vulnerability gradation criteria were depended on the national regulations. Exemplification indicates that the vulnerability of chengbihe reservoir was 0.89 that belong to high vulnerability.The last, the quantitative model for risk assessment was established by risk quantity "risk degree is product of danger degree and vulnerability" based on risk and vulnerability assessment theory. The risk degree is divided and evaluated by grade. Exemplification indicates that if the risk degree of chengbihe reservoir under moderate, the limited water level in each season can be established as:185.00 meters for the per-flood season and major season, 185.00 meters～186.50 meters for post-flood season.