摘要 過往研究表明，滑移速度會顯著影響滑山崩滑移帶的強度，而且水對滑 移帶的影響也被認為是一個關鍵因素。然而，關於此影響的文獻討論仍不足 夠，且仍在爭論之中。為了更深入地研究滑移速度和排水條件對山崩滑移帶 強度的影響，本研究以在正向應力為 1 MPa 及較大滑移速度範圍（從 10-7 m/s 到 1 m/s）的實驗條件對純高嶺土上進行了一系列旋剪試驗。在徑向排水條件 下，將試體夾在兩個不透水的圍岩之間以鐵氟龍環包覆，然後將其放入浸水 容器中。本研究還評估了浸水條件下摩擦特性與溫度變化之間的相關性。結 果表明，穩態摩擦係數在滑移速度從 10-7 m/s 到 10-5 m/s 時到達 0.2，然後在 10-4 m/s 時略微上升到 0.26、在 10-3 m/s 時上升到 0.3、並在 10-2 m/s 時到達 0.4、 接下來在 10-1 m/s 下降至 0.3。而在 1 m/s 的實驗條件下摩擦係數為滑移弱化 且穩態摩擦係數等於 0.14，這顯示了在浸水條件下之結果不同於先前研究的 氣乾且飽和條件下的實驗結果。另外在實驗過程中的溫度紀錄為在低滑移速 度（從 10-7 m/s 到 10-3 m/s）下保持在攝氏 25 – 26 度左右，然後在 10-2 m/s 時 逐漸增加到攝氏 32 度，接下來在 10-1 m/s 的速度顯著地升至攝氏 60 度，最後 以 1 m/s 的速度升至攝氏 75 度。然而，這項研究表明了高嶺土的線性熱膨脹 是在剪切過程產生的，與軸向位移的變化無關。 關鍵詞：旋轉剪切試驗、高嶺土、速度相依性、排水條件、溫度測量。;ABSTRACT Researches have suggested that slip rates can significantly influence the strength of the slip zones of landslides, and the effect of water on the slip zones is also proposed as a crucial factor. Nevertheless, efficient reports on this process are still limited and are continue being debated. In order to dig deeper into the roles of slip rate and drainage condition on the strength of the slip zones of the landslides, a series of rotary shear tests were conducted on a wide range of shear velocity (from 10-7 to 1 m/s) with normal stress of 1 MPa on kaolinite clay. For the control of radial drainage condition, samples were sandwiched by two impermeable-holders and covered by a Teflon ring. The system then being submerged into water tank. This research also assesses the correlation between the friction characteristics and the temperature changes in the submerged condition. The results illustrated that the steady-state friction coefficient reached 0.2 at a slip rate from 10-7 m/s to 10-5 m/s and followed by a slightly raised to 0.26 at 10-4 m/s, 0.3 at 10-3 m/s, and reached 0.4 at 10-2 m/s before dropping to 0.3 at 10-1 . The friction coefficient at 1 m/s shown the slip-weakening behavior with steady-state friction equal 0.14, indicated that the submerged condition is different to the dry and saturated conditions from previous studies. Temperature measurement results during the tests were maintained at around 25 – 26 degrees Celsius at a low slip rate (from 10-7 m/s to 10-3 m/s), then gradually increased to 32 degrees Celsius at 10-2 m/s, and significantly raised to 60 degrees Celsius at 10-1 m/s and 75 degrees Celsius at 1 m/s. However, this study proved that the linear thermal expansion of kaolinite clay had been created by the shearing process, not related to the changing of axial displacement. Keywords: Rotary shear test, kaolinite, velocity dependency, drainage condition, temperature measurement.
