上部净空的英文

• upper clearance

• 上部:    headpiece; ridge
• 净空:    headroom; freeboard; clearan ...
• 顶部净空:    head clearance
• 净空:    headroom; freeboard; clearance◇净空高度(拱梁等下面) head room; 净空损失 clearance loss
• 上部:    headpiece; ridge◇上部建筑 top-out; 上部截槽 overcut; 上部结构 [土] superstructure; 上部矿层 overlying seam