ballast bed
短語詞組
- asphalt cemented ballast bed 瀝青道床
- integrated ballast bed 整體道床
- integral ballast bed 整體道床
- width of ballast bed 道床寬度
- ballast bed finisher 平整道碴機
- track on ballast bed 碎石道床軌道
- elastic integral ballast bed 彈性整體道床
- integrate ballast bed 整體道床 返回 ballast bed