土釘擋土結構最佳化設計之探討

Investigation of Optimum Design of Soil-Nailed Retaining Structures

范嘉程(Chia-Cheng Fan)

《地工技術》 98期 (2003/12) Pp. 27-38

https://doi.org/10.30140/SG.200312.0003

摘要

土釘擋土結構或邊坡穩定工程之土釘設計配置多為由坡頂至坡趾採等距、等長度之均勻配置，此種設計配置雖能提供足夠之邊坡穩定作用，惟就土釘材料使用之經濟性與邊坡穩定安全性之需求而言，土釘於邊面上之均勻幾何配置並非為最佳設計。本文就下列各項影響土釘擋土結構或邊坡安全穩定性之因素進行探討，包括：1）土釘之傾斜角度；2）土釘材料之抗彎勁度；3）土釘於邊坡不同高度之配置長度；4）土釘於邊坡面上之配置位置等。本文結合土釘－土壤互動之力學機制及非線性有限元素數值模式為分析架構，探討土釘之配置方式與材料抗彎性質對邊坡穩定貢獻之影響，並以邊坡穩定安全係數為評估依據，本文之研究成果可提供土釘擋土結構最佳化設計之參考。

關鍵字

土釘 ； 最佳化設計 ； 安全係數 ； 土釘－土壤互動機制 ； 有限元素法

並列摘要

Soil nailing is normally designed with uniform length and equal spacing for the soil nailed walls and slopes. Uniform arrangement of soil nailing on the retaining walls and slopes may meet the requirement of stability. However, it may not be the optimum design in terms of the economic concern. Factors affecting the stabilization of soil nailed structures and slopes are investigated through: (1)inclination of soil nailing; (2)bending stiffness of soil nailing; (3)length of soil nailing at different elevations; (4)location of soil nailing on the outward surface of the walls or slopes. Investigation of mechanical behavior of soil-nail interaction is carried out in this study. Effect of deployment and bending stiffness of soil nailing on the contribution of stabilization of walls and slopes are assessed in terms of factor of safety, analyzed with the nonlinear finite element methodology. Findings of this study are helpful to the optimum design of retaining walls or slopes stabilized with soil nailing.

並列關鍵字

soil nailing ； optimum design ； factor of safety ； soil-nail interaction ； finite element method