关键词: 黏聚力, 柳杉, 稳定系数, 拉伸强度

Abstract: [Objective] Shallow landslides is relatively frequent in Beichuan county of Sichuan province.Therefore,our objective was to study the effects of Cryptomeria fortunei roots of different ages on slope stability in this area.[Method] Determination the length of 3-,6-and 9-year yearold C. fortunei root in soil within different depths were measured in length,and calculate its vertical weakening coefficient was calculated.The measuring the tensile strength power and strength of root of different diameters and tensile strength of the root were analyzed.The soils were transported back to investigate root soil shear specimen shear strength,and a simple calculation to calculate of factor of slope stability factor.[Results] βvalue of 9-year-old C. fortunei root was the highest.There were no clear differences in tensile power and strength when root diameter was smaller.However,the differences became significant when the diameter >4 mm.The direct shear specimen cr was the best in 9-year-old C. fortunei.Cohesion was decreased when soil water content was relatively high.The existing vegetation increased stability coefficient by 33.53%-88.93% compared to bare slope.[Conclusion] Root biomass increased with C. fortunei ages and reinforced role of roots in the slope stability was improved.

Key words: cohesive strength, Cryptomeria fortunei, stability factor, tensile strength