參數研究中，依據Hong等人(2005)所提出模型邊坡與原型間的系統相似律關係，配合前人建議的臨界滑移量觀念，求得60°~90°陡坡於不同地震力作用下所需的最小釘長。此外，基於最小滑移量的原則選擇邊坡的最佳土釘傾角，經分析邊坡坡度為60°、70 °、80°及90°之最佳土釘傾角分別為48°、43°、37°及25°，亦即，邊坡坡度越陡最佳土釘傾角越緩。最後，觀察土壤阻尼比與彈性模數於塊體動態行為分析中，對上塊體相對變形量與延遲現象的影響。 This study applies Newmark method with two wedge failure mode to analyze the sliding behavior of steep nailed-slops under seismic excitation. The analytic model has considering decay of the soil internal frictional angle when occur lager shear displacement. In order to confirm the validity of the mode, results of the present study are compared with those obtained from shaking table tests (Chen, 2002). A preliminary discussion regarding the deformation of upper block is also proposed. By comparing preceding steps of analytic block deformation with experimental observations, proper stiffness attenuation in the analysis can be obtained. Analytic results showed that prediction of two wedge sliding block method from the present study and those of shaking table test have good agreement when the nailed slopes belong to translation failure mode (model 1). The results underestimate displacement of sliding block when the nailed slopes tend to rocking failure mode except model 3. Due to incremental sliding shear displacement considering the decay of internal frictional angle of the soil to be contributive to improve the results in incipient collapse phase. In the results of slope deformation analysis are close to the observation from shaking table tests before the incipient collapse. However, the soil strength discrepancy between the original and the incipient collapse phase, the results from this study are lower than shaking table tests when nailed-slopes are into the incipient collapse phase. In accordance with the critical sliding displacement concept, the shortest nails lengths for steep slopes are obtained based on the similar relationship between the reduced scale model and the prototype-scale structure (Hong et al., 2005). The optimum nail inclinations are respectively 48°, 43°, 37° and 25° for slope angle 60°, 70°, 80° and 90°. The effects of damping ratio and elastic modulus of soil mass are also considered in the study.
