短語詞組短語rock blasting in cut 路塹石方爆破blasting cut out height 切口高度blasting cut length 切口長度position of blasting cut 切口位置blasting cut method 掏槽方式height of blasting cut 爆破切口高度blasting cut height 爆破缺口高度blasting cut out 爆破切口 返回 blasting cut