根據對深開挖之研究，可利用總應力與有效應力分析來預測土壤的應力應變行為，然真實土壤行為應該是根據有效應力原理，但綜觀有效應力分析結果卻相對不理想。所以本研究先選用台北國家企業中心(TNEC)案例做分析基礎，利用不同分析模式反覆驗證，以求得正確、合理之有效應力分析方法。
此外，本研究另外考慮40m及80m兩種不同邊界條件案例，並且分別提高不同區域內的土壤勁度參數，以便找出利用既有簡單的有效應力模型，卻能夠更真實模擬小應變區域範圍內開挖行為之特性。從分析結果顯示，若使用PLAXIS-HS model分析時，在開挖邊界底部之區域考慮較大的解壓再壓模數(Eur^ref)，可模擬理想的小應變行為特性。
為了驗證數值分析之參數正確性，本研究同時針對台北沉泥質黏土進行三軸K0壓密排水於不同應力路徑下之解壓再壓試驗，並同時施作彎曲元件試驗。試驗結果顯示，在CK0D_AE_UR試驗下無應變軟化之現象，而其解壓再壓模數(Eur_sec)約等於分析提高勁度之解壓再壓模數(Eur^ref)，而解壓再壓楊氏模數與50％極限強度之正割楊氏模數的比值(Eur_sec⁄E50_sec)，與分析建議之3倍有段落差，另排水狀態下之波森比(ν_ur)與分析程式中所建議之0.2則相當相近。

According to previous study on deep excavation, the stress-strain behavior of soils can be predict by T.S.M. & E.S.M.. However, the real soil behavior should be based on the principle of effective stress, but result of effective stress analysis is relatively unsatisfactory. In this study, we selected the case of the Taipei National Enterprise Center (TNEC) to be an analysis basis, and then use different analytical method to obtain the correct and reasonable effective stress analysis method.
In addition, a series of parameteric study with 40m and 80m of boundary is carried out analysis with increase of stiffness in different regions is performed. A more realistic simulation result can be obtained by considering the small strain behavior. The analysis showed that the use of PLAXIS-HS model analysis, with increasing the Eur^ref at the bottom part of excavation, with result in a better result.
Finally, in order to verify the numerical analysis, this study conduct K0 consolidation drainage triaxial test (CK0D) at different stress paths with unloading and reloading. Bender element tests was performed as well. The results show that no strain softening behavior under CK0D_AE_UR test. And then, the unloading and reloading secant stiffness (Eur_sec) approximately equal to the reference unloading and reloading secant stiffness (Eur^ref) in the analysis. The ratio of unloading and reloading secant Young's modulus and the secant Young's modulus (Eur_sec⁄E50_sec) at 50% of ultimate strength is higher than the suggestion in PLAXIS. The drained Poisson’s ratio (ν_ur) is found to be close to 0.2.

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