藤枝林道 5.4K 及6.7K 邊坡潛在崩塌地之探討

Investigating Potential Landslides at 5.4K and 6.7K on the Tengjhih Forest Roads

林泓麒(Hung-Chi Lin)

指導教授 ： 林金炳

國立屏東科技大學/工學院/土木工程系所/碩士(2013年)

https://doi.org/10.6346/NPUST.2013.00159

摘要

屏東林管處所管轄藤枝(荖濃溪)林道，沿線全長約為20公里，為通往藤枝森林遊樂區與周邊聚落主要道路。藤枝林道因受先天性地質條件脆弱加上溯源侵蝕與坡面風化等因素影響，每逢颱風豪雨常導致邊坡崩塌。98年8月8日莫拉克風災挾帶豪大雨量，造成藤枝林道多處路基嚴重流失與邊坡崩塌等嚴重災害。考量具有潛在崩塌之因素，選定林道兩處道路邊坡作為調查研究樣區，分別為5K+400m以及6K+700m。取得二試區鑽探及現地監測資料進行分析，再利用擬靜態STABL 極限平衡分析程式，模擬兩處邊坡於平時、暴雨及地震各狀態下邊坡之穩定性，研判該地區破壞行為機制以及可能滑動面之位置，由分析結果所得安全係數與設計規範比較，其安全係數低於規範者，則施加穩定邊坡之結構再進行分析，分析結果期能提供管理單位對於藤枝林道後續護坡工程施作之參考。

關鍵字

藤枝林道 ； STABL ； 邊坡穩定分析

並列摘要

Tengjhih (Laonong) path, 20km in length, is under administration of the Pingtung Forest District. It is the only and important road to reach Tengjhih Forest Recreation Area and its nearby villages. Along Tengjhih forest roads, due to fragile geological conditions, heavy rainfall, headwater erosion, and weathering processes, slopes often collapse. On 2009.08.08, Typhoon Morakot with a heavy rain that hit Tengjhih forest roads,along which part of roadbed was eroded seriously and hillsides were harmfully damaged. The research adopts 5K+400m and 6K+700m sites to evaluate the potential mudflow and landsides along forest road. The study takes following processes: Firstly, subsurface drilling and monitoring to obtain data which will be analyzed for the two slopes. Secondly, using STABL to perform a static simulation, under rainstorm and earthquake, by using limit balance method to evaluate hillside stability. Thirdly, after judging this area’s damage mechanism and the possible location of slip surface, the study compares the analytical results of safety factor with design specification. Fourthly, if safety factor is lower than a critical value, it would proceed another analysis of the slope with remediation measures being simulated.Finally, the results of analysis provide authorized officials to gain as a reference for Tengjhih forest roads’ follow-up conservation of hillside project.
Keyword：Tengjhih forest roads, STABL, Slope stability analysis

並列關鍵字

Tengjhih forest roads ； STABL ； Slope stability analysis

參考文獻

11. 林俊宏，2011，「藤枝林道4.5K崩塌地邊坡穩定分析」，碩士論文，國立屏東科技大學，土木工程研究所。

16. 許中立、吳重君、施保呈，2010，「藤枝林道莫拉克災損情形調查」，水保技術，第2期，105-117頁。

23. 楊凱勝，2003，「FLAC與STABL程式於邊坡穩定分析之比較研究」，碩士論文，中原大學，土木工程研究所。

34. 潘如蕙，2006，「剪力強度折減法應用於層狀土壤邊坡之穩定性研究」，碩士論文，國立成功大學，資源工程研究所。

35. 蔡明君，2007，「以降雨特性研究阿里山公路邊坡崩塌預警管理」，碩士論文，國立成功大學，土木工程研究所。