本研究以數值模擬成果建立一套液化後淺基礎變形之評估流程，利用分析區域之現地資料，以數值方法模擬區域液化後淺基礎之變形行為，利用分析案例之淺基礎變形資料進行多變數迴歸，確立現地液化後淺基礎之評估變形流程。數值模擬考慮現地土層分布與建物調查資料簡化後建立數值模型，其中考量到建物結構細節收集不易，建物採用剛性較高之彈性系統進行假設，以設計地震反應譜相符之地表加速度歷時作為模型輸入運動，計算液化後淺基礎之貫入沉陷與差異沉陷引致之傾角，對淺基礎變形之各影響因子進行分析，分析結果顯示貫入沉陷會隨著建物接觸應力與液化層厚度增加而增加，而隨著地表非液化層、基礎寬度和相對密度增加而減少。研究結果顯示貫入沉陷與基礎特徵之關係緊密，不宜利用自由場沉陷之計算結果與貫入沉陷進行連結。所有分析案例之淺基礎變形結果建立一迴歸公式，其迴歸公式結果與模擬之變形結果高度相關，進一步利用此迴歸公式計算，結合傾角-貫入沉陷關係式可推估淺基礎之傾角，所建立流程可快速取得現地淺基礎液化後變形量。

This study establishes an assessment procedure for the post-liquefaction deformation of shallow foundations, based on numerical simulation results. Using in-situ data from the study area, numerical methods are employed to simulate the deformation behavior of shallow foundations in the region after liquefaction. The deformation data from the analysis cases are then used to perform a multiple regression, thus establishing an assessment procedure for in-situ post-liquefaction shallow foundation deformation. The numerical simulations consider the simplified distribution of soil layers and building survey data to create numerical models. Given the difficulty in collecting detailed building structural information, buildings are assumed to be rigid elastic systems. The ground acceleration time histories corresponding to the design earthquake response spectrum are used as input motion for the model. The simulations calculate the penetration settlement and inclination by differential settlement of post-liquefaction shallow foundations. Various factors influencing shallow foundation deformation are analyzed. Results indicate that penetration settlement increases with building contact stress and liquefiable layer thickness but decreases with non-liquefiable surface layer thickness, foundation width, and relative density. The study shows a close relationship between penetration settlement and foundation characteristics, suggesting that it is inappropriate to link the calculation results of free-field settlement with penetration settlement. A regression formula is established based on the deformation results of all analyzed cases, and the results of this regression formula show a high correlation with the simulated deformation results. This regression formula, combined with the inclination-penetration settlement relationship, can be used to estimate the inclination of shallow foundations. The established procedure allows for a quick determination of post-liquefaction deformation of in-situ shallow foundations.

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