Abstract:

Based on the analysis of the influence of random factors to water level simulation results, groundwater flow stochastic simulation model could provide important basis for risk management and decision-making of groundwater resources. The authors took Hun River’s alluvial fan as research area, adopted the Monte-Carlo method to build random forecast model of regional groundwater and forecast the risks of rising groundwater level under compressive exploitation. The results indicate that, hydraulic conductivity is the most sensitive factor for groundwater levels, and the specific yield is the secondary sensitive factor. The sensitivities of hydraulic conductivity of riverbed and infiltration coefficient of precipitation have lower sensitivity, and the sensitivities is proportional to the hydraulic and specific yield. Although compressing the exploitation quantity of groundwater can effectively prevent the cone of depression to expand, under the condition of compressive exploit of groundwater at an annual rate of 5.0%, the groundwater water level will rise in the average of 3.3 m. However, it will also bring groundwater seepage risks to underground engineering, and the lower the safe groundwater level designed, the higher risk of groundwater seepage to the underground engineering.

Key words: parameter uncertainty, random model, risk forecast, Mente Carlo