青藏公路边坡防护试验研究

The results brought out in the trials of slope protection along Qinghai-Tibet Highway are presented in this paper. The trials were carried out simultaneously at 5 sites in Qinghai-Tibet Plateau from 2000 to 2002. Altitudes at the experimental sites range between 4 240 m and 5 040 m. 4 sites are in permafrost area, and 1 site is in seasonally frozen ground. According to the trials of slope protection, vegetation is preferred to protect slopes along Qinghai-Tibet Highway. Road-GoodR, a chemical stabilizer, is proved as a good material for slope protection, and soil engineering system, combined with vegetative component and grade stabilization structures is proved as the best slope protection measure in these are as. The results showed that high-altitude areas at an altitude lower than 5 040 m, annual average temperatures higher than -5.6 ℃ and annual rainfall more than 262.2 mm, slopes can be protected using vegetative components.Trials for plant species selection proved that cold resistant grasses, Elymus nutans and Elymus sibiricus can be used for vegetation recovery along Qinghai-Tibet Highway. The results demonstrated that high-altitude areas at an altitude lower than 5 040 m, annual average temperatures higher than -5.6 ℃ and annual rainfall more than 262.2 mm, could be replanted. Hydroseeding proved to be a good planting technique, and mulch materials benefited vegetation recovery in such area.The experiment also proved that planting could improve slope stability, protect the ecological environment, and improve the roadside landscape.