本研究利用試體為南投縣眉溪中上游之河砂，試體尺寸為長300mm、寬300mm、高250mm/200mm，在不同單位重14kN/m^3 、15kN/m^3 、16kN/m^3及各種圍壓下，進行氣壓缸應力控制乾砂界面靜態直接剪力試驗，以及震動台應力控制乾砂界面反覆直接剪力試驗(應力振幅漸增、固定應力振幅)，從而得到各實驗之剪應力與水平位移量關係等數據，再根據實驗數據求取動態背骨曲線土壤剪應力-變位雙曲線模型、修正H-D模型模型所需之參數代入公式，並依此公式建立模型用以預測土壤之乾砂界面反覆剪動行為，再與先前之實驗數據作圖比較，並評估模型符合程度。
本研究根據實驗結果與模型預測結果得知：一、由於應變速率的增加，氣壓缸應力控制之乾砂界面直接剪力試驗計算所得摩擦角大於位移控制之乾砂界面直接剪力試驗計算所得摩擦角。二、由於應變速率的增加，震動台應力控制應力振幅漸增乾砂界面反覆直接剪力試驗計算所得摩擦角大於氣壓缸應力控制之乾砂界面直接剪力試驗計算所得摩擦角。三、相同單位重情況下，尖峰剪應力會隨著圍壓上升而增加，所對應之水平位移量也會隨著圍壓上升而增加。相同圍壓情況下，尖峰剪應力會隨著單位重上升而增加，所對應之水平位移量隨著單位重上升而減少。四、震動台應力控制之固定應力振幅乾砂界面反覆剪力試驗結果顯示，土壤初始剪動時會有硬化情況，但剪動到一定程度時，試體的硬化程度會慢慢降低。五、於尖峰剪應力之前的反覆迴圈，可使用修正H-D模型預測，預測結果與實驗符合程度高。六、土壤殘餘狀態行為，可使用Newmark(1965) 塊體滑動理論估算破壞後的位移量。七、以本研究的修正H-D模型參數製作方法製作的位移控制界面反覆直接剪力試驗修正H-D模型，預測結果比歷來的論文研究結果準確。

In order to understand the soil behavior under dynamic loading and model the relationship between cyclic shear stresses and shear displacements on the soil to soil interface, a medium-scale direct shear test apparatus is uesd. The direct shear tests under stress control include monotonic sand to sand interface tests with pneumatic cylinder and cyclic sand to sand interface tests with shaking table using a poorly graded river sand.
To simulate the behavior of sand to sand interface subjected to cyclic shear loads, the hyperbolic model (Huang, 2013) and the modified Hardin-Drnevich (H-D) model are used. The hyperbolic model (Huang, 2013) is used to simulate the backbone curve and the modified Hardin-Drnevich (H-D) model is used to simulate the hysteresis loop. Curve fitting from experiment data were carried out to determine model parameters, and the model-predicted stress displacement relationships are compared with the experimental ones.
The hyperbolic model (Huang, 2013) satisfactorily simulates the backbone curve of sand subjected cyclic shearing under dynamic loading. Before the soil specimen reaches the peak point, the modified Hardin-Drnevich (H-D) model simulates the hysteresis loop of sand very well. But it can not simulate the hysteresis loop of sand when specimen is destroyed. However, the displacement of sand when specimen is destroyed can predict with Newmark's sliding block theory.

1. Al-Douri, R. H. and Poulos, H. G. (1992) “Static and cyclic direct shear tests on carbonate sands” Geotechnical Testing Journal, GTJODJ, Vol. 15, No. 2, pp. 138-157.
2. Collios, A., Delmas, P. and Girous, J. P. (1980) “Experiments on soil reinforcement with geotextiles” The Use of Geotextiles for Soil Improvement, ASCE National Convention, Portland, ASCE, pp. 53-73.
3. De, A, and Zimmie, T.F. (1998) “Estimation of dynamic interfacial properties of geosynthetics,” Geosynthetics International, Vol.5, No.1-2, pp.17-39
4. Das, B. M. (2010) “Principles of geotechnical engineering” Cengage Learing, 7th
ed, Chapter 12, pp. 372-373.
5. Desai, C. S. and Drumm, E. C. (1986) “Determination of parameters for a model for the cyclic behavior of interfaces” Earthquake Engineering and Structural Dynamics, Vol. 14, pp. 1-18.
6. Carrubba, P., Massimino, M.R., Maugeri, M., (2001) “Dynamic friction of geosynthetic interfaces by shaking table tests. ” International Waste Management and Landfill Symposium, vol. 3, pp. 567–576.
7. Duncan, J. M. and Chang, C. Y. (1970) “Nonlinear analysis of stress and strain in soils” Journal of Soil Mechanics and Foundation Division, ASCE, Vol. 96, No. SM5, pp. 1629-1653.
8. Yegian, M.K., and Lahlaf, A.M. (1992) “Dynamic interface shear strength properties of geomembranes and geotextiles,” Journal of Geotechnical Engineering, ASCE, Vol.118, No.5, pp.760-778, 1992
9. Hardin, B. O. and Drnevich, V. P. (1972) “Shear modulus and damping in soil” Measurement and Parameter Effect, ASCE, Vol. 98, No. SM6, pp. 603-624.
10. Huang, C.-C. , Hsieh, H.-Y. and Hsieh, Y.-L. (2014) “Hyperbolic models for a 2-D backfill and reinforcement pullout” Geosynthetics International, Vol. 21, No. 3, pp. 168 –178.
11. Ingold, T. S. (1982) “Some observations on the laboratory measurement of soil-geotextile bond” Geotechnical Testing Journal, Vol. 5, No. 3, pp. 57-67.
12. Jewell, R. A. and Wroth, C. P. (1987) “Direct shear test and reinforced sand” Geotechnique, Vol. 37, No. 1, pp. 53-68.
13. Yegian, M.K, and Kadakal, U. (1992) "Geosynthetic interface behavior under dynamic loading,”Geosynthetics International, Vol.5, No.1-2, pp.1-16, 1998
14. Koerner, R. M. (1998) “Designing with geosynthetics” Fourth Edition, Prentice Hall.
15. Lambe, T. W. and Whitman, R. V. (1979) “Soil Mechanics SI Version” John Wiley and Sons, New York.
16. Masing, G. (1926) “Eigenspannungen and verfestigung beim Messing” Proceedings of the 2nd International Congress on Applied Mechanics, Zurich, pp. 332-335.
17. O’Rourke, T. D., Druschel, S. J. and Netravali, A. N. (1990) “Shear Strength Characteristics of Sand Polymer Interfaces” Journal of Geotechnical Engineering, Vol. 116, No. 3, pp. 451-469.
18. Lo Grasso, S. A., Massimino, M. R., and Maugeri, D. I. C. A. (2002). “Dynamic analysis of geosynthetic interfaces by shaking table tests,” International Conference on Geosynthetics, Vol. 4, pp. 1335-1338.
19. Vardanega, P. J. and Bolton, M. D. (2013) “Stiffness of clays and silts: Normalizing shear modulus and shear strain” Journal of Geotechnical and Geoenvironmental Engineering, Vol. 139, No. 9, pp. 1575-1589.
20. Ramberg, W. and Osgood, W. R. (1943) “Description of stress-strain curves by three parameters” National Advisory Committee on Aeronautics, Technical Note, No. 902.
21. Richards, E. A. and Scott, J. D. (1985) “Soil geotextile frictional properties” Second Canadian Symposium on Geotextiles and Geomembranes, Edmonton, pp. 13-24.
22. Williams, N. D. and Houlihan, M. P. (1987) “Evaluation of interface friction-properties between geosynthetics and soil” Proceedings of the 87 Geosynthetics Conference, New Orleans, Vol. 2, pp. 616-627.
23. Zhang, J., Andrus, R. D., and Juang, C. H. (2005) “Normalized shear modulus and material damping ratio relationships” Journal of Geotechnical and Geoenvironmental Engineering, Vol. 131, No. 4, pp. 453-464.
24. Inn Joon PARK, Min Woo SEO, Jun Boum PARK , Soo Young KWON, Jong Sung LEE (2004) “Estimation of the dynamic properties for geosynthetic interfaces” , 13th World Conference on Earthquake Engineering , Paper No. 3210
25. Newmark, N. M. (1965) “Effect of earthquake on dams and embankments”Geotechnique, Vol. 15, No 2, pp. 139-159.
26. 廖泓韻 (2013)，「以微觀角度探討顆粒狀材料在直剪試驗下行為」，國立中央大學土木研究所碩士論文。
27. 徐浩怡 (2017)，「土壤之反覆直接剪力行為與模式化」，國立成功大學土木研究所碩士論文。
28. 魏嘉伶 (2017)，「承受反覆剪力之砂土與地工合成物界面行為模式研究」，國立成功大學土木研究所碩士論文。