Summary: | 碩士 === 國立雲林科技大學 === 環境與安全工程系碩士班 === 93 === The study of the previous researches was based on the assumptions of an isotropic and homogeneous aquifer. In fact, the characteristics of a real aquifer are anisotropic and heterogeneous. In the analyzing methods of horizontal anisotropic test, hydraulic scholars obtain the in-situ data from few wells that can’t represent the real horizontal anisotropic hydraulic quality of the aquifer. In the heterogeneous hydraulic test, the design of experimental instrument and the higher price of monitoring equipments both influence the feasibility of in-situ experiment. Therefore, in this study, pumping tests horizontal anisotropic and vertical heterogeneous was conducted through a group of monitoring wells established on the campus of National Yunlin University of Science and Technology to estimate hydraulic parameter in-situ aquifer.
In the analysis process, the data of hydraulic properties of the aquifer taken from more than four monitoring wells were found to be better than Neuman’s (1984) three-well method. The results of this study are that the principal transmissivity (Tα) and lateral transmissivity (Tβ) are 3.30E-04 (m2/s) and 2.00E-04 (m2/s) respectively; the principal hydraulic conductivity (Kα) and lateral hydraulic conductivity (Kβ) are 1.88E-05 (m/s) and 1.25E-05 (m/s) respectively; the isotropic effective transmissivity Te is 2.40E-04 (m2/s); and the storage coefficient S is 3.22E-03. The angle between the direction (α)of anisotropic coordinates(α,β)and the axis of normal coordinates(X,Y) is 39.32 degrees clockwise from the X-axis. The result showed irregularity concerning some parts of the well distance as well as change of water level, which proves the testing field is a heterogeneous aquifer. This result showed an anisotropic characteristic of hydraulic parameters, agreeing with Bakr et al. (1978) that heterogeneous aquifers have anisotropic characteristics theoretically. The study found that the analysis of the vertical heterogeneous test reveals the lower price of the experimental instrument and equipment that the study designed can be used to discuss heterogeneous quality in the in-situ aquifer.
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