The Study of Confined Aquifer Hydraulic in Tianmu Area

• Main Authors: Cheng-Chun Lin, 林正浚
• Other Authors: 倪至寬
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/dp94y8

碩士 === 國立臺北科技大學 === 土木與防災研究所 === 96 === For a construction project that involves deep excavation, it is generally a common practice to conduct an thorough in-situ geologic investigation of its underground soil at the initial stage, as to get a picture of the composition of the soil, and to evaluate the risk that might be encountered during excavation period, and to come up with the right choices of construction methods, equipments and machines as well, so as to finish the project as scheduled, within budget, and without safety problems. The Tianmu area is located at the north side of Taipei basin. The soils under Tianmu area are mainly weakly clay layer and Ansan rock layer. The Ansan rock layer is itself a confined aquifer. Therefore, It must be evaluated whether the weight of clay above Ansan rock layer will overcome the uplifting water pressure in the confined aquifer while work of deep excavation is underway in this area, so as to avoid construction failure caused by heaving and uplifting. This research is focusing on getting the correct hydraulic parameters and planning the quantity and position of pumping wells through pumping test in site and the well theory for the construction project executed in Tianmu area. Hopefully, the possible influence range and settlement due to dewatering of Ansan rock layer can be obtained, and the safety of construction can be improved. The results of this research could also be used as references for construction projects with deep excavation and by dewatering method in Tianmu area.