微透水岩体单孔抽水试验渗透系数的分析——以西非某水电站为例

抽水试验成本较高,耗时长,而单孔抽水试验获取的试验数据有限,且紊流、井损等因素对水位影响较大,从而影响参数计算精度;同时,实际抽水试验常在多种复杂边界条件下进行,如试验孔有临河时,需结合多种含水层模型,使实际抽水试验条件尽可能与理论模型条件相近,选择合适的模型计算,相互比较验证,求取岩土体渗透系数;将计算成果与有其他水文地质试验结果比较,综合确定渗透系数,进一步提高了岩土体渗透系数的合理性。

Permeability Analysis of Slightly Permeable Rock based on Single Hole Pumping Test in a Hydropower Station in West Africa

Pumping test is often used to determine the permeability of rocks. However,the pumping test is high-cost and time consuming. Also,the accuracy of the permeability coefficient obtained is often unsatisfying due to the limited data received from the single hole pumping test and influences of turbulent flow and well loss on water level measurement. A permeability analysis based on single hole pumping test with complex boundary conditions is presented. In the analysis,various aquifer models are examined and an appropriate model is chosen to accurately simulate the real conditions of the pumping test. The calculated permeability coefficient is then compared and verified with results from other geologic tests,which confirms its accuracy.