根據研究結果顯示，飽和所產生之膨脹現象會造成土壤結構及初始勁度參數的改變。為求得更貼近真實狀況之土壤正規化參數，本研究將考慮飽和膨脹對土壤勁度造成之影響，於三軸試驗飽和階段，將試體之圍壓與反水壓差值設定為現地土體之殘餘有效應力，並進行三軸K0壓密不排水軸向壓縮及軸向伸張試驗，於受剪過程中，將進行三次解壓再壓試驗，藉以求得台北粉土質黏土之正規化不排水土壤強度及勁度參數。本研究於兩種不同受剪應力路徑的情況下，發現所得之Eui/σ'vc結果很相近，其範圍介於527~572；而當兩種不同受剪應力路徑於相同應力位階下進行解壓或再壓，所得Eur/σ'vc之值亦很接近。於不排水軸向壓縮受剪試驗所求得之Eui/Su平均值約為1816，Eu50/Su之平均值為281。從試驗結果也發現，Eur值同樣具有正規化之現象。

For diminishing the influence of swelling during saturation in the triaxial test, the difference between cell pressure and back pressure should be equal to the residual effective stress of soil sample. According to the literatures, the stiffness of soil reduced if the swelling during saturation occurred. In order to ascertain more realistic soil parameters, the K0 consolidated undrained triaxial compression and extension (CK0U_AC, CK0U_AE) test with three unloading-reloading steps were performed. One set of test consist of three different vertical consolidation stress (σ'vc). In this study, the normalized undrained shear strength and stiffness parameters of normally consolidated Taipei silty clay were investigated such as Su/σ'vc, Eui/σ'vc, Eu50/σ'vc, Eur/σ'vc, Eui/Su, Eu50/Su and Eur/Su. The experimental results of CK0U_AC and CK0U_AE showed the value of Eui/σ'vc was close to each other with range from 527 to 572. The value of Eur/σ'vc of CK0U_AC and CK0U_AE was also similar when the stress level was almost the same. Thus, the Eur seemed that has the normalized beha-vior to σ'vc. The average of Eui/Su and Eur/Su on the CK0U_AC test were 1816 and 281 respectively.

1.秦中天、鄭在仁及劉泉枝(1989)，「台北沉泥之不排水剪力強度與過壓密比之關係」，中國土木水利工程學刊，第一卷，第三期，第245-250頁。
2.劉泉枝、秦中天及謝旭昇(1991)，「非均向壓密及主應力轉變對松山層土壤剪力強度之影響」，中國土木水利工程學刊，第三卷，第一期，第83-88頁。
3.喬國華(1992)，「台北粉土質黏土在不同應力路徑下之力學行為」，國立台灣科技大學營建工程系碩士學位論文。
4.張聰耀(1996)，「台北沉泥質黏土之變形特性研究」，國立台灣科技大學營建工程系碩士學位論文。
5.龔東慶(2003)，「考慮台北沉泥質黏土小應變行為之深開挖地表沉陷分析」，國立台灣科技大學營建工程系博士學位論文。
6.鄧福宸(2005)，「異向性小應變三軸試驗儀之研發」，國立台灣科技大學營建工程系碩士學位論文。
7.陳欣儀(2011)，「探討不同應力路徑下台北黏土之不排水勁度劣化行為」，國立台灣科技大學營建工程系碩士學位論文。
8.富國技術工程股份有限公司(2013)，「聯合報系企業總部新建工程基地土壤地質調查及大地工程分析報告書-A基地-」。
9.ASTM. (2010). “Standard test methods for laboratory determination of water (moisture) content of soil and rock by mass.” D2216-10, West Conshohocken, PA.
10.ASTM. (2010). “Standard test methods for liquid limit, plastic limit, and plasticity index of soils.” D4318-101, West Conshohocken, PA.
11.ASTM. (2011). “Standard test methods for one-dimensional consoled-tion properties of soils using incremental loading.” D2435/D2435M-11, West Conshohocken, PA.
12.Burland, J. B., and Symes, M. J. (1982). “A simple axial displacement gauge for use in the triaxial apparatus.” Ge ́otechnique, 32(1), 62-65.
13.Baldi, G., and Hight, D. W. (1988). “State-of-the-art: A reevaluation of conventional triaxial test methods.” Advanced Triaxial Testing of Soil and Rock, ASTM STP 977, ASTM, West Conshohocken, PA, 219–263.
14.Clayton, C. R. I., Khatrush, S. A., Bica, A. V. D., and Siddique, A. (1989). “The use of hall effect semiconductors in geotechnical instrum-entation.” Geotech. Test. J., 12(1), 69-76.
15.Cho, W., Holman, T. P., Jung, Y. H., and Finno, R. J. (2007). “Effects of swelling during saturation in triaxial tests in clays.” Geotech. Test. J., 30(5), 378-386.
16.Choo, J., Jung, Y. H., Cho, W., and Chung, C. K. (2013). “Effect of pre-shear stress path on nonlinear shear stiffness degradation of cohesive soils.” Geotech. Test. J., 36(2), 1-8.
17.Finno, R. J., and Chung, C. K. (1992). “Stress-strain-strength responses of compressible Chicago glacial clays.” J. Geotech. Engrg., 118(10), 1607-1625.
18.Goto, S., Tatsuoka, F., Shibuya, S., Kim, Y. S., and Sato, T. (1991). “A simple gauge for local small strain measurement in the laboratory.” Soils Found., 31(1), 169-180.
19.Hight, D. W. (2003). “Sampling effects in soft clay: An update on Ladd and Lambe (1963).” Soil Behavior and Soft Ground Construction, Cambridge, MA, 86–121.
20.Holtz, R. D, and Kavacs, W.D (1981). An introduction to geotechnical engineering, Prentice-Hall, New Jersey.
21.Jardine, R. J., Symes, M. J., and Burland, J. B. (1984). “The measure-ement of soil stiffness in the triaxial apparatus.” Ge ́otechnique, 34(3), 323-340.
22.Kokusho, T. (1980). “Cyclic triaxial test of dynamic soil properties for wide strain range.” Soils Found., 20(2), 45-60.
23.Ladd, C. C., and Lambe, T. W. (1964). “Strength of ‘Undisturbed’ Clay Determined from Undrained Tests.” Proceedings of the Symposium on Laboratory Shear Testing of Soils, ASTM Special Technical Publication, West Conshohocken, PA, 361, 342–371.
24.Ladd, C. C., and Foott, R. (1973). “New design procedure for stability of soft clays.” J. Geotech. Engrg., 100(7), 763~786.
25.Lo Presti, D. C. F., Pallara, O., Puci, I. (1995). “Modified commercial triaxial testing system for small strain measurements. Preliminary resu-lts on Pisa clay.” Geotech. Test. J., 18(1), 15-31.
26.Ladd, C. C., and DeGroot, D. J. (2003). “Recommended practice for soft ground site characterization: Arthur Casagrande lecture.” Proc., 12th PanAmerican Conf. on Soil Mechanics and Geotechnical Enginee-ring, Cambridge, MA.
27.Landon, M. M. (2007). “Development of a non-destructive sample quality assessment method for soft clays.” Ph.D. thesis, Unicersity of Massachusetts Amherst, Amherst, MA.
28.Mayne, P. W., and Kulhawy, F. H. (1982). “K0-OCR relationships in soil,” J. Geotech. Engrg., 108(6), 851-872.
29.Skempton, A. W. (1954). “The pore-pressure coefficients A and B.” Ge ́otechnique, 4(4), 143–147.
30.Skempton, A. W., and Sowa, V. A. (1963). “The behavior of saturated clays during sampling and testing.” Ge ́otechnique, 13(4), 269–290.
31.Santagata, M. C. (1999). “Factors affecting the initial stiffness and stiff-ness degradation of cohesive soils.” Ph.D. thesis, MIT, Cambridge, MA.
32.Teng, F. C. (2010). “Prediction of ground movement induced by excavation using the numerical method with the consideration of inherent stiffness anisotropy.” Ph.D. thesis, National Taiwan University of Science and Technology, Taipei, R.O.C..