台11線11K+200崩塌地破壞因子及治理對策

台11線為花蓮通往台東主要道路之一因緊鄰海岸山脈受先天性地質條件脆弱及坡面風化等因素影響，每逢颱風豪雨常導致邊坡崩塌。105年9月梅姬颱風挾帶豪大雨量，造成台11線11k+200處邊坡土壤嚴重流失與崩塌等嚴重災。考量具有潛在崩塌之因素，選定台11線11k+200處道路邊坡作為調查研究樣區。取得樣區鑽探及現地監測資料進行分析，再利用STABL極限平衡分析程式，模擬坡於平時、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台11線後續護坡工程施作之參考。

關鍵字

台11線；邊坡穩定分析；崩塌

並列摘要

The 11 county road is one of the main roads leading Hualien to Taitung. Due to the fragile congenital geological conditions and the weathering of the slopes in the immediate vicinity of the coastal mountains, the typhoon and heavy rain often cause the slope to collapse. In September of the 105th year, the typhoon of Meiji took a heavy rainfall, causing severe disasters such as serious loss and collapse of the 11k+200 slope on the 11 county road. Considering the factors of potential collapse, the roadside slope of 11k+200 on the 11 county road was selected as the investigation and study area. The sample area drilling and local monitoring data were obtained for analysis, and then the STABL limit equilibrium analysis program was used to simulate the stability of the slope in the normal, heavy rain and earthquake states, and the damage behavior mechanism and the position of the possible sliding surface were determined. The safety factor obtained from the analysis results is compared with the design specification. If the safety factor is lower than the standard, the structure of the stable slope is applied and analyzed. The analysis result period can provide reference for the management unit to implement the 11 county roads follow-up slope protection project.