In order to make full use of the continues pumping test data to estimate the hydraulic conductivity(K), the transmissivity(T)and the storage coefficient(μ*)of different head depression cones in a confined aquifer, a dimensionless analytical solution of drawdown transients with variable pumping rates was derived based on the Theis formula and the principle of superposition. Furthermore, a new type curve method was proposed. The in-situ pumping test was conducted to obtain the drawdown record perturbed by stepwise rates. Then, the drawdown curve was used to match the corresponding type curve. After that, this method selects one match point and records its coordinate values on both the type curve and the real drawdown curve. By substituting these recorded values into related formulas, the hydraulic parameters of the confined aquifer can be determined. This method was applied to a field pumping test conducted at a southern highway in Wuxi, Jiangsu Province, China. The type curve matching process is implemented in stages. Field test results reveal that the hydraulic conductivity of the confined aquifer with the 2-3 silt layer are 5. 12×10-4 cm/s, 2. 54×10-3 cm/s and 2. 83×10-3 cm/s respectively, which are corresponding to three-stage stepwise pumping rates.
周志芳,王萍,李雅冰,等.一种求解承压含水层水文地质参数的新配线法[J].河海大学学报(自然科学版),2019,47(1):7-12.(ZHOU Zhifang, WANG Ping, LI Yabing, et al. A new type curve method for estimating hydrogeological parameters of confined aquifers[J]. Journal of Hohai University (Natural Sciences),2019,47(1):7-12.(in Chinese))Copy