結合導電度數據及土壤水力特性評析淺層邊坡穩定性

Combining Electrical Data and Soil Hydraulic Properties to Evaluate the Stability of Shallow Landslides

楊亞欣(Ya-Sin Yang) ； 葉信富(Hsin-Fu Yeh) ； 柯建仲(Chien-Chung Ke) ； 陳耐錦(Nai-Chin Chen)

《中華水土保持學報》 55卷1期 (2024/03) Pp. 1-13

https://doi.org/10.29417/JCSWC.202403_55(1).0001

摘要

本研究探討現地土壤含水量與導電度之關係，從而建立以導電度為變量之抗剪強度評估模型。本研究以嘉義縣八寶寮崩塌地為案例，透過現地導電度及水文參數進行關聯與建模，並透過拓展非飽和土壤的抗剪強度模型，使抗剪強度模型與基質吸力及導電度相關。為驗證模型的合理性，本研究採用有限元素數值模式及局部安全係數評估邊坡穩定性。分析結果顯示局部安全係數變化與抗剪強度變化具有一致性，顯示本研究以導電度為變量建立之抗剪強度模型能做為傳統水文評估的替代方案。本研究提出的架構亦可應用於未飽和土壤水力相關分析。

關鍵字

淺層滑坡 ； 土壤水力特性 ； 導電度 ； 邊坡穩定性

並列摘要

This study investigated the relationship between soil water content and electrical conductivity to construct a model of the shear strength of shallow landslides with electrical conductivity as the primary variable. The Babaoliao landslide site in Chiayi County, Taiwan, was selected as a case study. First, based on in-situ electrical conductivity measurements and hydrological parameters, the study modeled the correlation between electrical conductivity and hydrological parameters. Next, the study extended the shear strength model to unsaturated soils to correlate the shear strength model with matric suction and electrical conductivity. For empirical validation of the proposed model, this study adopted a finite-element numerical model and used the local factor of safety to assess slope stability. Slope stability analysis revealed that the shear strength of the landslide was consistent with observed variations in the local safety factor, indicating that the shear strength model with electrical conductivity as the primary variable established in this study can serve as a useful alternative to conventional hydrological assessments of landslide stability. The model proposed in this study was further extended to analyze the hydraulic properties of the unsaturated soil of the Babaliao landslide.

並列關鍵字

shallow landslides ； soil hydraulic properties ； electrical conductivity ； slope stability

參考文獻

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