碩士 / 國立中興大學 / 水土保持學系所 / 101 / The influence of rainfall, tide waves and landforms on water table will cause different fluctuations and wave celerity on coastal aquifers. The data of groundwater level are mainly obtained from the observation wells. However, it is very expensive to set up the instrument and wells. Therefore, by means of solving governing equations with boundary conditions, we can better understand the groundwater level fluctuations.
The present study considers the unconfined aquifer with an impervious sloping bed, a beach slope, and various rainfalls. Therefore, based on the Dupuit-Forchheimer assumptions two zones of a coastal aquifer are defined. One zone near the coast is with rainfall and the other inland zone is without rainfall. Next, the study employed the Chapman’s(1980) modified Boussinesq equation as governing equations. After linearization of these equations and applying the moving boundary method proposed by Li et al.(2000) to the beach slopes, the analytic solutions of groundwater table fluctuations are presented.
The analysis of one-dimensional and two-dimensional models of groundwater fluctuations are carried out respectively. We discuss the effects of tidal waves and rainfall on the groundwater fluctuations in a coastal unconfined sloping aquifer. The solutions of the non-rainfall area satisfy the boundary conditions by adding the factor e^(-p(X-1)). In comparison with previous analytical solutions, the results agree very much. The groundwater level increases quickly with the upward inclined angle of the impermeable bed to maximum and then decreases until reaching to the non-rainfall area. The groundwater level induced by tidal waves and rainfall increases linearly with the downward inclined angle of the impermeable bed to further inland gradually. Moreover, the groundwater level also increases as the beach angle becomes small.
| Identifer | oai:union.ndltd.org:TW/101NCHU5080021 |
| Date | January 2013 |
| Creators | Hsiao-Ting Hsu, 徐筱婷 |
| Contributors | 謝平城 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 123 |
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