場鑄樁在複層地層軸向承載行為之探討

近年來鑽掘樁為大型建築物首選的深基礎。然而在世界各地有許多地方的土層構造為複層地層，因此在基樁的分析與設計必須考量由不同土層所提供的阻抗力。本研究蒐集台北地區的樁載重試驗資料進行複層地層的分析模型建立及發展可靠度設計的方法。研究中使用部分安全係數設計法，針對粘土層，砂土層，礫石層和岩石層等不同的地層進行可靠度的設計。本研究依台北地區載重資料庫資料進行樁身單位阻抗的回饋分析，將台灣所得的資料與過去前人的研究結果進行了比較並得出一致的結果後，建立了三種分析模型，進而將此三種分析模型應用於可靠度設計中，再呈獻針對三種設計模型進行可靠度率定分析成果，最後並建議部分安全係數設計法的設計程序及步驟。

關鍵字

鑽掘樁；部分安全係數；承載力；可靠度設計；不確定性

並列摘要

Drilled shafts have been the preferred foundation system for infrastructure and buildings over the past decades. Ground profile with multiple layers is often encountered in several metropolises around the world. Analysis and design of drilled shafts in this type of strata should consider resistances contributed from different geomaterial types. A load test database of drilled shafts in this type of ground profile was compiled for study of three analysis models and development of reliability based design (RBD) equations. The proposed RBD format utilizes multiple safety factor design to consider different level of safety measure required for clay, sand, gravel, and rock layers. In this study, three analysis models for different types of geomaterials were calibrated using the load test database. Whenever possible, results from past studies were compared, and consistent results can be obtained. The three developed analysis models were subsequently used for development of RBD equations. The methodologies for multiple safety factor calibration are given, the calibrated results are discussed, and finally procedures are outlined for selection of multiple resistance factors for the foundation design.

並列關鍵字

drilled shafts ； multiple strata ； capacity ； reliability based design ； uncertaint

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