本研究以沉泥質砂土在三種不同尺寸的流槽中進行實驗，分別為長1.75 m、寬1.35 m、高0.7 m，土層厚度0.28 m、長1.94 m、寬0.645 m、高0.7 m，土層厚度0.38 m及長2.29 m、寬0.645 m、高0.84 m，土層厚度0.42 m，堆置一坡角為30°的邊坡，並進行模擬降雨試驗，探討邊坡在豪雨中的破壞機制、土砂流出特性及土層厚度改變所造成之影響。於邊坡的坡趾、坡中與坡頂埋設有土壤水份計和孔隙水壓計，用以監測降雨時邊坡內部含水量與孔隙水壓變化，並藉由邊坡模型匯流口所收集邊坡破壞後所排出雨水及土砂之混合物，來觀察其排放率與混合物體積濃度變化情形。
研究結果發現，邊坡中段底部與邊坡坡趾底部的土壤水份計曲線到達峰值時的時間點之差值可參考做為關鍵避難時間，此關鍵避難時間值隨著降雨強度增強而縮短。邊坡中土壤水份計有兩種反應曲線，第一種為直線上升型，第二種為兩階段上升型。第二種反應曲線較容易發生於降雨強度低且土層較厚之中間部位。由砂土排放歷線之發動期觀察得知，降雨強度對於邊坡破壞發動時機的影響為負相關但非線性。

A series of artificial rainfall tests were performed on three sizes were 0.28 m, 0.38 m,
0.42 m thick sandy slopes with a slope angle of 30°. Wooden sand boxes with 1.75 m long, 1.35 m wide and 0.7 m high, 1.94 m long, 0.645 m wide and 0.7 m high, and 2.29 m long, 0.645 m wide and 0.84 m high were used with soil moisture sensors and a data acquisition system to monitor the interior soil moisture response to the rainfall infiltration. The present study features the measurement of solid and water discharge from the slope subjected to rainfall. This substantiates the investigation into the relationship between the soil moisture response and the solid discharge (or waste) process.
Experimental evidences revealed that the time difference of slope middle and slope toe moisture response curve’s peak value able to be critical refuge time, that time decrease attach to rainfall intensity increase. There were two kinds response curve of moisture sensor, first is direct rising, second is two steps rising. The second kind response curve usually appear at small rainfall intensity and middle of slope. Observed the starting period of soil discharge curve revealed the negative relationship between rainfall intensity and critical slope failure time but nonlinear.

誌 謝 I
論文摘要 II
Abstract III
目錄 IV
第一章 緒論 1
1.1前言 1
1.2研究動機與目的 1
1.3論文內容概述 3
第二章 文獻回顧 4
2.1邊坡破壞之形式 4
2.2邊坡破壞之原因 6
2.3降雨與邊坡破壞之研究 7
2.4 土石流體積濃度之相關研究 12
第三章 實驗設備與律定方式之介紹 14
3.1實驗流槽與週邊設備 14
3.1.1 實驗流槽 14
3.1.2 人工模擬降雨系統 19
3.2 感測儀器 22
3.2.1 土壤水份計 22
3.2.2孔隙水壓計 23
3.3 感測儀器律定與降雨均勻律定 24
3.3.1 土壤水份計 24
3.3.2 水壓計 26
3.3.3 降雨強度與均勻度 27
第四章 室內模型邊坡試驗 30
4.1 試驗內容 30
4.1.1 試驗土壤性質 30
4.1.2 一號實驗流槽(厚度0.28 m) 31
4.1.3 二號實驗流槽(厚度0.38 m) 32
4.1.4 三號實驗流槽(厚度0.42 m) 33
4.2 試驗步驟 34
4.3 混合物之體積濃度的量測方式 37
4.4 土壤水份計與孔隙水壓計關鍵時間定義 38
第五章 試驗結果說明 39
5.1 土體厚度0.38 m 二號流槽各別實驗結果及綜合討論 39
5.1.1砂土排放歷線 39
5.1.2土體內部含水量變化 47
5.1.3 土壤水份計關鍵時間點與土壤水份計埋設位置之關係 53
5.1.4 土壤水份計關鍵時間點與不同降雨強度之關係 55
5.1.6 土體內部孔隙水壓變化 59
5.2 土體厚度0.42 m 三號流槽各別實驗結果及綜合討論 64
5.2.1砂土排放歷線 64
5.2.2土體內部含水量變化 71
5.2.3 土壤水份計關鍵時間點與土壤水份計埋設位置之關係 80
5.2.4 土壤水份計關鍵時間點與不同降雨強度之關係 82
5.2.5 不同降雨強度下土壤水份計關鍵時間點與破壞特徵之關係 85
5.2.6 土體內部孔隙水壓變化 88
5.2.7 孔隙水壓計關鍵時間點與不同降雨強度之關係 93
5.2.8 不同降雨強度下孔隙水壓計關鍵時間點與破壞特徵之關係 95
5.3 土體厚度0.28 m 一號流槽、土體厚度0.38 m二號流槽與土體厚度0.42 m三號流槽實驗結果綜合比較討論 97
5.3.1 砂土排出累積量百分比例與歷時之關係 97
第六章 結論 103
參考文獻 105

弗來施曼，C.M.(1986) 姚德基譯，泥石流，科學出版社。
范正成、吳明豐(1996) 台灣地區田間人工降雨機之研究。
黃景川(1999）土壤力學，三民書局。
詹錢登(2000) 土石流概論，科技圖書股份有限公司。

Brand,E.W.,1982.”Analysis and Design in Residual Soil s ,”Proceedings of the ASCE Geotechnical Engineering Division Specialty Conference- Engineering and Construction in tropical and Residual Soils, Honolilu, Hawaii, pp.89-141,January 11-15.

Eckersley,J.D.,1990.”Instrumented laboratory flow slides.”Geotech
ique 40, No. 3,pp.489-502.

Lavigne, F. and Suwa, H. (2004) Contrasts between debris flow, hyperconcentrated flows
and stream flows at a channel of Mount Semeru, East Java,
Indonesia.Geomorphology.61,pp44-58.

Lumb,P.,1975.”slope failures in Hong Kong” Quarterly Journal of Engineering Geology,Vol.8,pp.31-65.

Lourenço, S. D.N., Sassa, K., Fukuoka, H. (2005), “Failure process and hydrologic response of a two layer physical model:Implications for rainfall-induced landslides” ,Geomorphology Vol.73 , pp.115~130.

Johnson,K.A.,andN.Sitar,1987.”DebrisFlow Initiation; An Investig ation of Mechanisms ,”University of California ,Department of Civil Engineering Report No.UCB/GT/87-02,University of California ,Berkeley, California,179pp.

Nishigaki,M.,Tohari,A.&Komatsu,M.,1999.”Predicting rainfall induce
d slope failures from moisture content measurement.”
Slope stability Engineering, Yagi, Yamagami&Jiang.pp465-469.

Orense R. and Shimoma S. 2004 .Instrumented Model Slope Failure due to Water Seepage. Journal of national Disaster Science, Volume 26,Number 1,pp15-26.

Varnes,D.J.1978，Slope movement types and processes ;in Landslides, analysis and control(R.L Schuster and R.J. Krizek eds.)：National Academy of Sciences,Special Report 176,Washington,D.C.,11-33