短语词组短语tieback sub 回接接头tieback prestress 锚杆预应力tieback equipment 回接装置tunnel tieback 隧道式锚碇tieback riser 回接立管tieback method 锚拉挡土墙施工法tieback stinger 回接插入管prestress tieback 预应力锚杆directional tieback 定向回接 返回 tieback