关键词: 卵漂石, 铅丝石笼, 西藏, 水土流失治理, 施工工艺

Abstract: Gravel and boulder gabion, which is economical, simple, permeable, flexible, and aesthetic, is widely applied to the blocking, bank protection, and gully stabilization works of water and soil loss control projects in Tibet autonomous region in China. We summarize that when gravel and boulder gabion is applied to retaining walls in various construction projects in Tibet, if the retaining height h≤1.5m, the shape of gravel and boulder gabion’s cross-section can be rectangular, trapezoid, and right trapezoid; while when 1.5m＜h＜5m, stepped rectangular section can be adopted. Moreover, when gravel and boulder gabion is applied to bank protection and shoal protection works (spur dike and longitudinal dike), stepped trapezoid and trapezoid cross-sections are mostly adopted. The embedded depth of gabion is determined according to erosion depth. When erosion depth is larger than 1.0m, the embedded depth of gabion should be controlled within 1.0m, best around 0.5m. In straight river segments with good foundation and less scouring, the length of longitudinal dike can be partitioned into segments according to the length of gabions per roll; whereas in bending rivers with scouring and non-uniform settlement, the length of longitudinal dike is recommended to be 8-15m. Practice proved that longitudinal dike and spur dike made of gravel and boulder gabions have good resistance to deformation and erosion. They can also work even when the foundation is scoured and collapsed under mountain torrents. After mountain torrents, better effect can be obtained to make up further bank protection project on the basis of the collapsed gabions.

Key words: gravels and boulders, gabion, Tibet, soil erosion control, construction technique