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为了研究元谋干热河谷区坡面表层土壤的抗侵蚀性能,通过对燥红土机械组成、团聚体组成、基质吸力、黏聚力c和内摩擦角φ等参数的分析,并用原状土进行冲刷试验测定土壤的抗冲指数ANS,探讨了这些参数对土壤抗冲性的影响。结果表明,土壤分散率和ANS(soilanti-scourability)呈一元三次多项式变化,随着分散率的逐渐增加,ANS逐渐下降,ANS随着平均重量直径MWD的增大呈幂函数增长,随着基质吸力、黏聚力c和内摩擦角φ的逐渐增加,ANS也呈对数函数增长;ANS与各力学参数的相关程度依次为:抗剪强度τf>φ>MWD>分散率>基质吸力>c,逐步回归表明,黏聚力c、平均重量直径MWD和抗剪强度τf与ANS呈较好的线性关系(R2复=0.983),偏相关系数(RMWD(0.915)>Rc(0.829)>Rτf(0.776))表明水稳性团聚体的稳定性、颗粒及团聚体之间的胶结凝聚力和土壤抵抗水流的剪切破坏力对ANS影响较大。
In order to study the anti-erosion performance of surface soils in Yuanmou dry-hot valley, the authors analyzed the mechanical composition, aggregate composition, matrix suction, cohesion c and internal friction angle φ of dry red clay, The soil anti-impact index ANS was measured, and the impact of these parameters on soil anti-scourability was discussed. The results showed that the soil dispersity and soilanti-scourability showed a one-way cubic polynomial change. With the dispersion rate increasing, the ANS decreased gradually. The ANS increased exponentially with the increase of the average weight diameter (MWD) , Cohesion c and internal friction angle φ gradually increase, ANS also showed a logarithmic function growth; ANS and the mechanical parameters of the order: shear strength τf> φ> MWD> dispersion rate> matrix suction> c, Stepwise regression showed that cohesion c, mean MWD and shear strength τf had a good linear relationship with ANS (R2 complex = 0.983) and partial correlation coefficient (RMWD (0.915)> Rc (0.829)> Rτf (0.776 )) Showed that the stability of water-stable aggregates, the cement cohesion between particles and aggregates, and the shear destructive power of soil resistance to water flow had a greater impact on ANS.