本研究對重模試體施加不同大小之前期反復荷重，探討前期反復荷重對試體剪力波速及液化阻抗之影響，並結合彎曲元件試驗及動力三軸試驗探討砂土剪力波速與液化阻抗之關係，及砂土受前期反復荷重後，對此關係之影響。以新店砂製作重模試體，試體壓密後先進行彎曲元件試驗求其剪力波速，接著進行動力三軸試驗求其液化阻抗。

研究結果顯示，重模試體之剪力波速越大其液化阻抗越高，將本研究所得之剪力波速與液化阻抗之關係和其他學者之研究成果互相比較，在相同正規化剪力波速時，本研究所得之液化阻抗介於Andrus and Stokoe (2000)及Zhou et al.(2005)之間。

前期反復荷重之影響方面，當試體承受一較小的前期反復荷重後其液化阻抗會增加，但前期反復荷重應力比(PCSR )超過了0.15後，其液化阻抗反而降低，前期反復荷重對剪力波速並沒有太大的影響，這也表示若要以剪力波速來推估液化阻抗，必須進行更完整試驗之探討，以釐清兩者之關係。

The research of this experiment is to discover the influence of previous cyclic loading on liquefaction resistance and shear wave velocity incurred in the reconstituted specimens imposed with various previous cyclic loading, in view to study the relationship between liquefaction resistance and shear wave velocity under previous cyclic loading. The tools used for the experiment are bender element test and cyclic triaxial test which will show us how reconstituted specimens are influenced by previous cyclic loading in terms of liquefaction resistance and shear wave velocity.Based on Hsin-Dian sand, the reconstituted specimens is made and consolidated, then put under bender element test to acquire shear wave velocity, followed by cyclic triaxial test to obtain liquefaction resistance.
The result shows,on the reconstituted specimens, the larger the shear wave velocity is, the higher the liquefaction resistance gets. Compare this result between the shear wave velocity and the liquefaction resistance from our experiement with those from other research results, it can be seen that under the same normalization shear wave velocity, the liquefaction resistance from this experiment falls between Andrus and Stokoe (2000) and Zhou et al.(2005).
On the influence of previous cyclic loading , we can see liquefaction resistance increases when specimens is imposed with small previous cyclic loading, but decreases while previous cyclic stress ratio ( PCSR ) goes beyond 0.15. On the other hand, the previous cyclic loading does not show obvious impact on shear wave velocity which indicates it would take more thorough tests and experiments to be able to conclude the liquefaction resistance via shear wave velocity.

1. 李志剛，「蘭陽平原砂土動態性質與液化阻抗之研究」，碩士論文，國立臺灣工業技術學院工程技術研究所營建工程組(1990)。
2. 吳偉特、夏啟明，細粒塑性程度對台北盆地粉泥質砂土液化特性之研究，第五屆大地工程學術研究討論會論文集，第1-10頁(1993)。
3. 林保延，利用彎曲元件試驗推估砂土動態性質之探討，碩士論文，國立臺灣科技大學學營建工程技術研究所(2005)。
4. 陳名利，以剪力模數評估砂土液化之研究，碩士論文，國立臺灣工業技術學院工程技術研究所營建工程組(1990)。
5. 陳堯中，土壤液化之機制及評估 ，土壤液化防災與補強技術研討會~營建自動化策略聯盟系列研討會之十~（2000）。
6. 陳界文，「細粒料特性對土壤抗液化強度之影響」，碩士論文，國立台灣大學土木工程研究所(2002)。
7. 黃朝聰，「冰凍融解過程對砂土液化阻抗及最大剪力模數之影響」，碩士論文，國立臺灣科技大學學營建工程技術研究所(2001)。
8. 黃信詳，「以現地冰凍土壤求得之剪力模數評估土壤之液化阻抗」，碩士論文，國立臺灣科技大學學營建工程技術研究所(2003)。

9. 游步上，台北盆地松山層粉土質砂之剪力模數與阻尼比，碩士論文，國立臺灣工業技術學院工程技術研究所營建工程組(1989)。
10. 曾清祥，砂土液化及穩定狀態之研究，碩士論文，國立臺灣工業技術學院營建工程技術研究所(1996)。
11. 楊沂恩，細料含量對砂土液化影響之研究，碩士論文，國立成功大學土木工程學研究所(1984)。
12. 廖廷勖，「過壓密對砂土動態性質及穩定狀態之影響」，碩士論文，國立臺灣科技大學學營建工程技術研究所(1998)。
13. 賴穎芳，以非均向壓密對砂土最大剪力模數與液化強度關係之影響，碩士論文，國立臺灣工業技術學院工程技術研究所營建工程組(1993)。
14. 簡連貴、李建中、許先才，冰凍取樣技術在粒狀土壤力學行為之研究，第五屆大地工程學術研究討論會論文集，第93-100頁(1993)。
15. 韓明憲，砂土最大剪力模數與液化阻抗關係之探討，碩士論文，國立臺灣工業技術學院營建工程技術研究所(1995)。
16. Andrus, R.D. and Stokoe , K.H., II., " Liquefaction Resistance Based on Shear Wave Velocity," Proceeding, NCEER Workshop on Evaluation of Liquefaction Resistance of Soils, ed. By T.L. Youd and I.M. Idriss, Tech. Report NCEER-97-0022, pp.89-128(1997).
17. Andrus, R.D. and Stokoe , K.H., II., "Liquefaction Resistance of Soils from Shear-Wave Velocity." Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol.126, No.8, pp.1015-1025
(2000).
18. Baig, S., Picornell, M. and Nazarian, S., "Low Strain Shear Moduli of Cemented Sand," Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol.123, No.6, pp.540-545(1997).
19. Clough, G.W., Iwabuchi, J., Rad, N.S. and Kuppusamy, T., "Influence of Cemention on Liquefaction of Sands," Journal of the Geotechnical Engineering Division, ASCE, Vol.115, No.8, pp.1102~1117(1989).
20. Dyvik, R. and Madshus, C., "Lab Measurements of Gmax Using Bender Elements," Advances in the Art of Testing Soils Under Cyclic Conditions, V. Khosla, Ed., ASCE, New York, pp. 186-196(1985).
21. Finn, W. D., Bransby, P.L., and Picreing, T., "Effect of Strain History on Loquefaction of Sand," Journal of the Soil Mechanics and Foundations Division , ASCE, June, 1970, pp.1917-1934. (1970).
22. Hardin, B.O. and Black, W.L., "Vibration Modulus of Normally Consolidation Clay," Journal of the Soil Mechanics and Foundations Division, ASCE, Vol.94, No.SM2, pp.353-369(1968).
23. Hardin, B.O. and Drenvich, V.P., "Shear Modulus and Damping in Soils: Design Equations and Curves," Journal of the Soil Mechanics and Foundations Division, ASCE, Vol.98, No.SM7, pp.667-692(1972).
24. Hardin, B.O., "The Nature of Stress-Strain Behavior of Soil," Conference on Earthquake Engineering and Soil Dynamics, ASCE, Vol.1, pp.3-90(1978).

25. Iwasaki, T., Tatsuoka, F., "Effect of Grain Size and Grading on Dynamic Shear Modulus of Sands," Soils and Foundations, Vol.17, No.3, pp.19-35(1977).
26. Iwasaki, T., Tatsuoka, F. and Takagi, Y., "Shear Moduli of Sands Under Cyclic Torsional Shear Loading," Soils and Foundations, Vol.18, No.1, Mar., pp.39-56(1978).
27. Ishihara, K. and Tadatsu, H., "Effecs of Over-consolidation and K0 Conditions on the Liquefaction Characteristics of Sands," Soils and Foundations, Vol.19, No.4, Dec., pp.59-68 (1979).
28. Kayen, R.E., Mitchell, J.K., Seed, R.B., Lodge, A., Nishi, S. and Coutinho, R., "Evaluation of SPT-, CPT-, and Shear Wave–Based Methods for Liquefaction Potential Assessment Using Loma Prieta Data," Proceedings, Fourth Japan-US Workshop on Earthquake Resistant Design of Lifeline Facilities and Countermeasures for Soil Liquefaction, Technical Report NCEER-92-0019, M. Hamada and T. D. O，Rourke, eds., Vol. 1, pp. 177-204(1992).
29. Lee, K.L. and Fitton, J.A., "Factors Affecting the Cyclic Loading Strength of Soil," Vibration Effects of Earthquakes on Soils and Foundations﹐ASTM﹐STP 450, pp.71- 95(1969).
30. Lohani, T.N., Imai, G. and Shibuya, S., "Determination of Shear Wave Velocity in Bender Element Test," Proceeding of Earthquake Geotechnical Engineering, Rotterdam, pp. 101-106(1999).
31. Peacock, W.H. and Seed, H.B., "Sand Liquefaction Under Cyclic Loading Simple Shear Conditions," Journal of the Soil Mechanics and Foundations Division, ASCE, Vol.9, No. SM3, pp.689-708(1968).
32. Pennington, D. S., Nash, D. F. T.,and Lings, M. L., "Horizontally Mounted Bender Elements for Measuring Anisotropic Shear Moduli in Triaxial Clay Specimens," Geotechnical Testing Journal, Vol. 24, No. 2, pp. 133-144(2001).
33. Robertson, P.K., Woeller, D.J., and Finn, W.D.L., "Seismic CPT for Evaluating Liquefaction Potential Under Cyclic Loading," Canadian Geotechnical Journal, Vol. 29, pp. 686-695(1992).
34. Seed, H.B. and Lee, K.L., "Liquefaction of Saturated Sand During Cyclic Loading," Journal of the Soil Mechanics and Foundations Division, ASCE, Vol.92, No.SM6, pp. 105-133 (1966).
35. Seed, H.B. and Idriss, I.M., "Shear Moduli and Damping Factors for Dynamic Respons Analysis," Report No.EERC pp.70-100, Earthquake Engineering Research Center, University of California, Berkley, Calif.(1970).
36. Seed, H.B. and Idriss, I.M., "Simplified Procedure for Evaluating Soil Liquefaction Potential," Journal of the Soil Mechanics and Foundations Division, ASCE, Vol. 97, No. SM9, pp. 1249-1273(1971).
37. Seed, H.B., Idriss, I.M., Makdidi, F., and Banerjee,N., "Representation of Irregular Stress-Time Histories by Equivalent Uniform Stress Series in Liquefaction Analyses," Report No. EERC 75-29, Earthquake Engineering Research Center, University of California at Berkeley(1975).
38. Seed, H.B., Mori, K., and Chan, C. K. "Influence of Seismic History on Liquefaction of Sand," Journal of the Geotechnical Engineering Division, ASCE, Vol.103, No.GT4, pp.257-271(1977).

39. Shen, C.K., Vrymoed, J.L. and Uyeno, C.K., "The Effect of Fines on Liquefaction of Sands," Proceedings of the 9th International Conference on Soil Mechanic and Foundation Engineering, Tokyo, Vol.2, pp.281-285 (1977).
40. Suzuki and Toki, "Effect of Preshearing on Liquefaction Characteristics of Saturated Sand Subjected to Cyclic Loading," Soils and Foundations, v 24,n 2, pp.16-28(1984).
41. Tokimatsu, K. and Uchida, A., "Correlation between Liquefaction Resistance and Shear Wave Velocity," Soils and Foundations, Vol.30, No.2, pp.33-42(1990).
42. Thevanayagam, S., Fiorillo, M. and Liang, J. "Effect of Non- Plastic Fines on Undrained Cyclic Strength of Silty Sands," Soil Dynamics and Liquefaction, pp. 115-123(2000).
43. Vaid, Y.P. and Chern, J.C., "Cyclic and Monotonic Undrained Response of Saturated Sands," ASCE National Convension Session on Advance in the Art of Testing Soils Under Cyclic Loading, Detroit , pp.120-147 (1985).
44. Viggiani, G. and Atkinson, J.H., "Interpretation of Bender Element Tests," Geotechnique ,Vol.45, No. 1, pp. 149-154(1995).
45. Youd, T.L., and Nobel, S. K., "Magnitude Scaling Factors," Proceeding, NCEER Workshop on Evaluation of Liquefaction Resistance of Soils, Nat. Ctr. For Earthquake Engr. Res., State Univ. of New York at Buffalo, pp. 149-165(1996).

46. Zhou, Y. G., Chen, Y. M., Ke, H., "Correlation of Liquefaction Resistance with Shear Wave Velocity Base on Laboratory Study Using Bender Element," Journal of Zhejiang University science, Vol.6, n 8, pp.805-812(2005).