• 沒有找到結果。

第五章 結論與建議

5.2 建議

1. 本研究假設地質參數之空間變異性具有指數型態之共變異函數,然而依 據現地狀況之不同此假設並非永遠合適,後續可進一步探討當共變異函 數為其他型態時(如球型等),對於區域可靠度所造成之影響。

2. 本研究目前僅考慮地質參數為風險因子(不確定性參數),然對於降雨引 發淺崩塌之模擬仍有許多其他重要之條件或參數存在相當高之不確定 性,例如初始地下水位與土壤厚度等,建議後續可將風險分析方法擴充 考慮這些參數之不確定性。

3. 未來可以不同之不確定性分析方法計算安全係數之統計特性,例如改良 一階二次矩法(Advanced first-order second-moment method)、羅森布魯斯 點估計法(Rosenblueth’s point estimation)或哈爾點估計法(Harr’s point estimation)等,並比較不同方法應用於降雨引發坡地淺崩塌之適用性。

4. 不同格網點間安全係數之相關性主要包含兩項來源,即(1)地質參數在空 間上之相關性;以及(2)格網點發生崩塌後,其造成之土砂流動或地形變 化對鄰近格網點安定性之影響。本研究已針對前述第(1)項進行分析並用 以評估區域可靠度,後續可進一步分析第(2)項因素。

5. 本研究所提出之分析方法可計算在不同整治率下區域可靠度不再發生 崩塌之可靠度,建議後續可進一步考慮不同整治率所需之經濟成本,並 評估區域可靠度與工程成本間之競合關係(trade-off curve),以作為決策 者擬定策略之參考。

6. 建議往後可進階考量水文條件之不確定性及不同降雨量下之重現期 距,配合本研究所提出之分析方法評估區域之年崩塌機率(the annual probability of a landslide occurring )。

參考文獻

王建峰,(2001),「九份二山順向坡滑動機制研究與殘坡風險評估」,國立 中興大學土木研究所,碩士論文。

打荻珠男,(1971),「ひと雨による山腹崩壞について」,新砂防。

付兵先、唐飛和趙峰,(2006),「岩石參數的地基承載力模糊可靠性分析」,

岩石工程技術,第20 卷,第 2 期。

陳本康,(2005),「石門水庫集水區崩塌特性及潛勢評估研究」,國立中興 大學水土保持學研究所,博士論文。

陳弘恩,(2005),「降雨引發坡地淺崩塌模式之建立與探討」,國立交通大 學土木工程學研究所,碩士論文。

陳爾義,(2002),「地下水浸潤及滲流對崩積土邊坡穩定影響之探討」,國 立海洋大學河海工程學系,碩士論文。

陳樹群,(2003),「水庫集水區土砂整治成效評估 2/2」,經濟部水利署。

楊錦釧、蔡東霖、黃安斌,(2007),「石門水庫集水區崩塌與庫區淤積風險 評估研究2/3」,經濟部水利署。

謝正倫,(2002),「流域土砂管理模式之研究 3/3」,經濟部水資源局。

羅文強、張倬元和黃潤秋,(1999),「邊坡系統穩定性的可靠性研究」,地 質科技情報,第18 卷,第 2 期。

蘇歆婷,(2007),「降雨引發坡地崩塌風險評估模式之建立與應用」,國立 交通大學土木工程學研究所,碩士論文。

Alonso, E. E. (1976)“Risk analysis of slopes and its application to slopes in

Canadian sensitive clays.”

Geotechnique , 26(3): 453-472.

Baecher, G., B., (1993). “Recent developments in measurement and modeling of clay behavior for foundation design.”

Geotchnical Error Analysis ,

Leture Notes of MIT Special Summer Course 1.6os,August 5-9.

Barabosa, M. R., Morris, D. V., Sarma, S. K.. (1989). “Factor of safety and probability of failure of rockfill embankments.”

Geotechnique

, 39(3):

471-483.

Baum, R. L., Savage, W. Z., Godt, J. W., (2002). “TRIGRS-a Fortran program for transient rainfall infiltration and grid-based regional slope-stability analysis.” US Geological Survey Open file report, 402-424, Virginia.

Carrara, A.,(1998). “Multivariate models for landslide hazard evaluation, a black-box approach.” Workshop on Natural Disasters in European Mediterranean Countries, 205-224, Perugia, Italy.

Carrara, A., Cardinali, M., Guzzetti, F.,(1992). “Uncertainty in assessing landslide hazard risk.”

ITC Journal

, 1992-2: 172-183.

Chang,Y.L.,Tsai,T.L.,Yang,J.C.,M.ASCE,Tung,Y.K.,(2007). “Stochastically optimal groundwater management considering land subsidence.”

Journal of water resources planning and management-ASCE,

133(6).

Chen, J. C., Jan, C. D., Lee, M. H.,(2007) .“Probabilistic analysis of landslide potential of an inclined uniform soil layer of infinite length: theorem.”

Environmental Geology

, 51: 1239-1248.

Chowdhury, R. N., Xu, D. W., (1995).”Geotechnical system reliability of slopes.”

Reliability Engineering and System Safety,

47:141-151,1995

Chowdhury, R. N., Xu, D. W., (1984).“Rational polynomial technique in slope stability analysis.”

Journal of Geotechnical Engineering Division

, 119(12):

1910-1928.

Christian T. J., Ladd, C.C., Baecher, G. B., (1992).“Reliability and probability in stability analysis.”

Stability and performance of slopes and embankments II

, STP 31 :1071-1111.

Christian T. J., Ladd, C.C., Baecher, G. B.,(1994). “Reliability applied to slope stability analysis.”

Journal of Geotechnical Engineering Division

, 120(12):

2180-2207.

Cornell,C.A.,(1967). “Bounds on the Reliability of Structural Systems.” Journal of the Structural Division ,ASCE,Vol.93,No.ST1,pp.171-200.

Cornell, C. A.,(1971). “First-order uncertainty analysis of soils deformation and stability.” In: Proc. 1st Int. Conf. On Application of Statistics and Probability to Soil and Structural Engineering, 129-144, Hong Kong.

Cressie,N.A.C.(1993).Statistics for spatial data, J. Wiley ,New York.

Crosta, G. B., Frattini, P.,(2003). “Distributed modeling of shallow landslides triggered by intense rainfall.”

Natural Hazards and Earth System Sciences

, 3: 81-93 .

Gelhar, L. W.,(1993).

Stochastic subsurface hydrology

, Prentice-Hall Inc., New Jersey.

Genz,A.(1992) “Numerical Computation of Multivariate Normal Probabilities.”

American Statistical Association, Institute of Mathematical Statistics, and Interface Foundation of North America,1(2):141-149.

Frattini, P., Crosta, G. B., Fusi, N., Negro, P. D.,(2004). “Shallow landslides in pyroclastic soil : a distributed modeling approach for hazard assessment.”

Engineering Geology

, 73: 277-295.

Harp, E. L., Jibson, R. W.,(1995). “Inventory of landslides Triggered by the

1994 Northridge, Californation Earthquake.” In: US Geological Survey Open-File Report,17: 95-213.

Hoek,E.,(1998),Rock Engineerint,pp.105-114.

Hovius, N., Stark, C. P., Allen, P. A.,(1997). “Sediment flux from a mountain belt derived from landslide mapping.”

Geology

, 25: 231-234.

Huang, S., L., Yamasaki, K.,(1993). “Slope failure analysis using local minimum factor-of-safe approach.”

Journal of Geotechnical Engineering

,ASCE,Vol.119,pp.1974-1990.

Husein Malkawi, A. I., Hassan W. F., Abdulla F. A.,(2000). “Uncertainty and reliability analysis applied to slope stability.”

Structural Safety

, 22:161-187.

Iverson, R. M., (2000).“Landslide triggering by rain infiltration.”

Water Resources Research

, 36: 1897-1910.

Keim , R. F., Skaugset , A. E.,(2003). “Modeling effects of forest canopies on slope stability.”

Hydrological Processes

, 17: 1457-1467.

Korup, O.,(2005). “Distribution of landslides in southwest New Zealand.”

Landslides

, 2:43-51.

Lan, H. X., Lee, C. F., Zhou, C. H., Martin, C. D.,(2005). “Dynamic characteristics analysis of shallow landslides in response to rainfall event using GIS.”

Environmental Geology

, 47: 254-267.

Li, K. S., Lumb, P., (1974).“Probabilistic design of slopes.”

Canadian Geotechnical Journal

, 24: 520-35.

Liu, C.N., and Wu,C.C.,(2007). “Mapping susceptibility of rainfall-triggered shallow landslides using a probabilistic approach.”

Environ Geol

.

Mays, L.W., and Tung, Y.K.,(1992). “ Hydrosystens engineering and

management.” McGraw-Hill ,New York.

Mckay, M. D., (1988).“Sensitivity and Uncertainty Analysis Using a Statistical Sample of Input Values”,

Uncertainty Analysis

, Y.Ronen,ed.,CRC Press,Inc., Boca Raton, FL.,145-186.

Mckay,M.D., Beckman, R.J., and Conover,W.J.(2000). “A comparison of three methods for selecting values of input variables in the analysis of output from a computer code.”,

Technometrics

,42(1),55-61.

Morgenstern, N. R., (1997).“Toward landslide risk assessment in practice.” In:

Cruden and Fell (eds.) Landslide risk assessment, 15-24, Balkema, Rotterdam.

Mostyn, G. R. and Li, K. S.,(1993). “Probabilistic slope analysis-State-of-Play.”

Proceedings of the conference on probabilistic methods in geotechnical engineering, 89-110, Canberra, Australia.

Mylopoulos, Y. A., Theodosiou, N .,and Mylopoulos, N. A .(1999). “A stochastic optimization approach in the design of an aquifer remediation under hydrogeologic uncertainty.”

Water Resources Management

,13(5),335-351.

Shou, K. J., Chen, Y. L.,(2005). “Spatial risk analysis of Li-shan landslide in Taiwan.”

Engineering Geology

, 80: 199-213.

Sivakumar Babu, G. L., Mukesh, M. D.,(2003). “Risk analysis of landslides-A case study.”

Geotechnical and Geological Engineering

, 21: 113-127.

Soeters, R., Westen, C. J. van, (1996).“Slope stability recognition, analysis and zonation.” In:

Landslides investigation and mitigation

. (eds.) Turner, A. K., Schuster, R. L., Transportation Research Board, special report 247:

129-177, National Academy Press, Washington.

Tang, W. H., Yucemen, M. S., Ang, AH-S.,(1976). “Probability-based short term design of slopes.”

Canadian Geotechnical Journal

,13(3): 201-215.

Tsai T. L. and Yang J. C.,(2006). “Modeling of rainfall-triggered shallow landslide.”

Environmental Geology

, 50(4): 525-534.

Van Westen, C. J., Van Duren, I., Kruse, H. M. G., Terlien, M. T. J., (1993).“GISSIZ: training package for geographic information systems in slope instability zonation.” ITC publ 15(1) and (2) ,ITC, Enschede, The Netherlands.

Van Westen, C. J., Rengers, and N., Terlien, M.T.J., Soeters, R., (1997).“Prediction of the occurrence of slope instability phenomena through GIS-based hazard zonation.”

Geologische Rundschau

, 86:

404-414.

Venmarcke, E. H., (1977).“Reliability of earth slopes.”

Journal of Geotechnical Engineering Division

, ASCE, 103(11):1227-46.

Wagner, B. J., and Gorelick, S. M. (1989). “Reliable Aquifer Remediation in the Presence of Spatially-Variable Hydraulic Conductivity - from Date to Design.” Water Resources Research,25(10),2211-2225.

Wolff, T. F.. (1985).“Analysis and design of embankment dam slopes: a probabilistic approach.” Ph.D. thesis, Purdue University, West Lafayette.

Wu, T. H., Kraft, L. M., (1970).“Safety analysis of slopes.”

Journal of Soil

Mechanics and Foundation Division

, ASCE, 96(2):609-630.

附錄A 拉丁超立方取樣方法 (Latin Hypercubic Sampling ,LHS )

作業程序:

1. 在求解空間中,選取所需取樣之參數X,及取樣組數K,並決定輸入參 數之機率分佈型態。

2. 將參數X 可能的範圍劃分為K個區間,每個區間被取中的機率皆為 1 K。 3. 在劃分的K個區間內隨機取樣一個樣本值,可得到K個隨機樣本。

4. 任意排列此K個隨機樣本,即完成取樣。

附錄 B 正交轉換(Orthogonal Transformation)

由於相關係數矩陣為對稱且正定(positive definite),利用 cholesky decomposition method 及特徵拆解法(eigenvector decomposition)將Rx進行拆

解:

其中,

Λ

為特徵值( eigenvalue )組成之對角矩陣;

V

為特徵向量(eigenvector) 組成之正規化矩陣。

1

X X 2

X =μ +σ ⋅ ⋅ Λ ⋅V Y (B.13)

式(B.13)為具相關性統計變數與無相關性統計變數之轉換式子。

圖B-1 正交轉換圖

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