Abstract:This paper describes the mechanism of sand fixations by grouting engineering and biological engineering . The grouting veins formed by pipe-g routing act as anchors , and adjacent grouting columns work like soil arches . The deep roots resulted from biological engineering act as anchors , and voluminous flat roots present a reinforcement effect .The authors consider that the combination of civil engineering measures with biological engineering measures can make the best of respective advantages , and thus achieve the effect of managing bothits root cause and symptoms .Finally , countermeasures on No.13 sanding-sliding slope in Zhongba section of the Sichuan-Tibet highway are briefly discussed .