摘 要
潛盾施工過程中因開挖面土壤應力的解放而造成地表沉陷，從過去之案例中知潛盾施工沉陷是無可避免的。由於施工沉陷是無可避免，所以於施工過程中所產生之沉陷量能合乎規範之要求為工程師所期望。本文係使用台北捷運土城線CD551標之施工監測資料，將監測點埋設之深度正規化建立任一深度之正規化數值與沉陷之關係式。另外由監測資料以Peck方式求得沉陷槽反曲點，將監測點埋設之深度正規化建立任一深度之正規化數值與沉陷槽反曲點關係式。工程師可由沉陷量及反曲點與正規化數值之關係，預估任一深度及距離之沉陷量。本文中亦利用施工監測資料及隧道地質與潛盾鑽掘記錄，建立潛盾施工參數與地表沉陷之相關趨勢。

ABSTRACT
Because of the soil stress release from the face of excavation, some surface settlement was created during the period of tunneling construction. Historic cases indicated that the surface settlement is inevitable. Since the surface settlement is inevitable in the construction stage, so, settlement amounts can comply with the requirements of specification is expected by engineers. Field driven log and instrumentation data of Tucheng Line Project CD551, MRT was used in this article. By means of normalizing the depth of instrumentation, than, the relationship between normalize data and settlement can be obtained. Furthermore, we can get length of the inflection point by means of Peck method, compare the normalize data with length of the inflection point. An equation can be established. Since relationship among the normalize data, length of the inflection point and settlement amounts has been created, than, engineer can predict settlement amounts at any position. The relationship among the boring log data, TBM driven log and instrumentation data has been analysis in this article also, and a tendency between TBM driven parameters and settlement can be observed.

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