淺談地質改良於軟弱粘土中深開挖之應用

A Note on Application of Ground Improvement in Deep Excavation in Soft Clay

林永光(Yung-Kuang Lin) ； 孫一鴻(I-Hung Sun) ； 呂芳熾(Fang-Chih Lu) ； 黃志祥(Chih-Hsiang Hwang)

《地工技術》 78期 (2000/04) Pp. 103-111

https://doi.org/10.30140/SG.200004.0007

摘要

地質改良經常應用於軟弱黏土中之深開挖工程，其目的在減少連續壁之變形量並增加開挖之穩定性，進而達到鄰房保護之目的。因地質改良施工不良或因灌漿工法選擇不當，造成地改樁體（樁徑、強度）無法達成設計之要求，導致基礎開挖失敗或無法達成鄰房保護目的之案例時有所聞；另設計方面因採用改良率過高或地質改良深度不足等設計觀念錯誤因素，在施工過程中造成開挖擋土結構外擠甚至擋土結構開裂損壞，或開挖過程中隆起失敗之個案亦不在少數。因此本文擬經由設計面及施工實務面探討，如何將地質改良成功的應用於軟弱黏土中之深開挖工程，提供給各位讀者參考。

關鍵字

地質改良 ； 軟弱黏土 ； 深開挖

並列摘要

Ground improvement have been widely used to support deep excavation in soft grounds mainly for the following objectives: to reduce diagram wall deformation during excavation; to increase wall stability; and to maintain existing structures' integrity immediately adjacent to the excavation. Nevertheless, occasionally excavation induced failures are still being reported. Some of the failures could be attributed to improper grouting procedures selected (resulting in insufficient treated column diameter and material strength); insufficient treatment depth used (resulting in bottom heave); and excessive treatment ratio used (resulting in bulging and/or cracking behind diagram walls).This paper focuses on various design and construction aspects of ground improvement. By using case histories, it demonstrates how the proper techniques and appropriate procedures should be used for ground improvement in association with deep excavation in soft ground.

並列關鍵字

ground improvement ； soft clay ； deep excavation