饱和—非饱和填埋场衬垫系统中水渗流规律的数值模拟

采用饱和—非饱和渗流场数学模型,通过室内试验测得的黏土渗透系数并运用数值模拟手段研究饱和—非饱和填埋场衬垫系统中水渗流规律。数值模拟结果分析表明：在饱和渗流场中水的运移速度明显大于处于非饱和状态下的运移速度,并导致在相同位置衬垫层处产生不同的压力水头,且随着时间的变化,非饱和渗流场下的压力水头远远小于饱和状态下的数值;此外,还验证了工程实际中采用渗透系数为10-7cm/s数量级黏土衬垫系统的合理性。该研究为分析渗滤液水分运移规律时采用非饱和渗流场提供理论数据,并验证所推荐的填埋场衬垫系统土工参数的正确性。

Numerical simulation of seepage in liner system under saturated-unsaturated condtion

The conductivity coefficient of clay is texted in indoor experiment,and the law of seepage in liner system under saturated-unsaturated condition is stydied by the method of numerical simulation based on the two mathemati- cal model of the seepage field. Numerical simulation results show that the velocity of water in saturated seepage field is obviously larger than that of unsaturated,thus causing distinct pressure heads in the same height of the two liner systems. Moreover,the pressure head in the condition of unsaturated is much smaller than that of saturated as time going by. In addition,the rationality of the adoption of clay in the order of magnitude of 10- 7cm / s in engineering practice. The theoretical data is provided to conduct us to use the unsaturated seepage when analyzing the migration of leachate from this study,and the correction of the recommended geotechnical parameters in landfill is verified.