木钙+玄武岩纤维对黄土边坡力学性能及抗蚀性的影响

Effect of Calcium Lignosulfonate+Basalt Fiber on Mechanical Properties and Erosion Resistance of Loess Slope

木钙与玄武岩纤维均可作为土壤改良剂,玄武岩纤维可有效提高土体黏聚力和抗剪强度,木钙可有效提高土体的水稳性和持水性,为探讨二者复合使用的效果,通过土工试验和人工降雨冲刷试验,研究了在黄土中单独掺加木钙、玄武岩纤维及二者复合掺加对黄土边坡力学性能及抗蚀性的影响。结果表明:玄武岩纤维和木钙复合使用可显著改善黄土的力学指标,木钙掺量为1.5%+玄武岩纤维掺量为0.4%是二者复合使用的最优配比,按此配比改良的黄土的黏聚力、内摩擦角与单掺1.5%木钙相比分别增大67.2%、17.8%,与单掺0.4%玄武岩纤维相比分别增大14.4%、9.8%,且崩解速率较素土显著降低;改良黄土边坡抗渗能力显著提高、渗透系数减小、雨水入渗减缓、抗蚀性显著增强,在雨强为50 mm/h、降雨时长3 h的情况下累计冲刷量比素土边坡累计冲刷量减少99.8%。

Both calcium lignosulfonate and basalt fiber can be used as soil amendments.Basalt fiber can effectively improve the cohesion and shear strength of soil,while calcium lignosulfonate can effectively improve the water stability and water holding capacity of soil.In order to explore the effect of their combined use,the effects of adding calcium lignosulfonate,basalt fiber and their combined addition on the mechanical properties and erosion resistance of loess slope were studied by soil tests and artificial rainfall erosion tests.The results show that the composite use of basalt fiber and calcium lignosulfonate can significantly improve the mechanical indexes of loess,and 1.5%calcium lignosulfonate plus 0.4%basalt fiber is the optimal dosage.Under the optimal ratio condition,the cohesion and internal friction angle of the improved soil have been increased by 67.2%and 17.8%respectively,compared with that of 1.5%calcium lignosulfonate and 14.4%and 9.8%respectively,compared with that of 0.4%basalt fiber.In addition,the disintegration rate is significantly lower than that of plain soil.The permeability of the improved loess slope has been increased significantly,the permeability coefficient decreased,the rainwater infiltration slowed down,and the corrosion resistance increased significantly.Under the condition of rainfall intensity of 50 mm/h and rainfall duration of 3 h,the cumulative brush amount is 99.8%less than that of plain soil slope.