斷層構造形成不透水面造成邊坡潛變案例之研究

A Case Study on the Slope Creep Caused by Impermeable Layer Formed by Fault

劉永修(Yeong-Suioug Liou)

指導教授 ： 施邦築

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00275

摘要

台灣地區地形陡峭，其中約占73.3%為山坡地外加地質構造複雜且降雨集中，邊坡穩定問題顯得格外重要。
台灣島係位於歐亞板塊及菲律賓海板塊兩地殼板塊的接合處，這兩板塊相互撞擠形成諸多斷層及伴隨地震產生，斷層為岩體中已產生相對位移的破裂面，斷層於發生位移時，在強壓和高摩擦力之下，將岩層粉碎，斷層帶內為被擾亂之岩層，可能由斷層泥(gouge)或斷層角礫(fault breccia)所組成，斷層泥不具透水性，常阻滯地下水流而增加局部之地下水壓，降低斷層帶之剪力強度，容易發生滑動。
研究中以臺北市政府產業發展局所屬位於南港區舊莊街二段336號之南港茶葉製造示範場，經長期監測中發現位該場區於斷層帶上，地層滑動持續進行中，監測資料顯示斷層構造形成不透水面造成邊坡潛變之影響，主要是由於降雨導致地下水位變化所造成，由相關資料研判茶製場在相同受地下水位上升變動之潛移滑動邊坡，經分析結果於設置擋土微型樁及橫向排水管後，邊坡之潛移速率可減少至1/10甚至更低。

關鍵字

斷層 ； 邊坡潛變 ； 有限元素分析法

並列摘要

Steep topography in Taiwan, about 73.3% area is hillside,.The geological structure is complex and concentrated rainfall. Slope stability is a particularly important problem.
Taiwan Island is located in the Eurasian Plate and the Philippine Sea plate junction of two tectonic plates, two plates collided with each other and cause number of fault accompanies earthquake. The fault has been produced for the mass relative displacement of the fracture surface. When fault occur displacement, under the extreme pressure and high friction, it will be crush rock. The rock is disturbed in fault zones may be composed of fault gouge or fault breccias. Non-permeable fault gouge is often block groundwater flow and increase the local groundwater pressure, reduce the shear strength of fault zones and occurring sliding easily.
In the study by the Nankang tea manufacture demonstration field which belongs to Department of Economic Development of Taipei City Government. Mainly located at No.336, Sec. 2, Jiuzhuang St., Nangang District, after the long-term monitor in discovery position this area in the fault zone, the mass slip continues to carry on, the monitoring data demonstrated that the fault structure forms the airtight water surface to cause the side slope to dive changes the influence, is mainly because rains causes the subsoil water level change to create, in is dived same by the correlation data evaluation tea system field the subsoil water level rise change moves the glide side slope, after the analysis result keeps off the earth miniature pile and the crosswise discharge pipe after the establishment, the side slope dives moves to the speed to be possible to reduce to 1/10 is even lower.

並列關鍵字

fault ； creeps of slopes ； finite element method

參考文獻

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