弯束预应力锚碇模拟施工试验研究

隧道锚因具有性价比高、环境扰动小的特点,成为山区中大型悬索桥理想的锚碇型式。隧道锚锚碇的预应力管道一般设有弯束转向部分。对于管道内灌注油脂的无粘结可换式锚碇,弯束转向部分设置了由分丝管组成的转向器。与直束管道相比,转向器的存在使得穿束、灌油、密封的困难增加了。本文针对湖南矮寨特大悬索桥,进行了弯束预应力锚碇模拟施工的试验研究：通过穿束试验检验穿束工艺的可行性,试验表明穿束顺利,钢绞线穿束过程中不会打绞;通过换索试验检验换索工艺的可行性,试验表明能顺利实现单根换索;通过灌油密封试验检验灌油工艺的可行性与密封效果,试验表明能顺利灌满孔道且系统无泄漏。通过模拟试验积累了经验,为实际工程及以后相似的工程提供借鉴。

Experimental study on simulated construction of bent beam prestressed anchorage

Tunnel anchors are ideal for large suspension Bridges in mountainous areas because of their high cost performance and low environmental disturbance. The prestressed pipe of the tunnel anchor is generally equipped with a bending beam steering part. For an unbonded replaceable anchor filled with grease in the pipe, a steering device composed of a splitter pipe is provided in the bending beam steering part. Compared with the straight pipe, the existence of the steering device makes it more difficult to thread, fill and seal the pipe. In this paper, an experimental study on the simulated construction of prestressed anchor with bent beam is carried out for Aizhai extra-large suspension bridge in Hunan province. The feasibility of the beam threading process is tested through the beam threading test, and the test shows that the beam threading is smooth and the steel strand will not be twisted during the beam threading process. The feasibility of cable changing process is verified by cable changing test, which shows that single cable changing can be realized smoothly. The feasibility and sealing effect of the oil filling process were tested by the oil filling sealing test, which showed that the hole could be filled smoothly and the system had no leakage. The experience accumulated through the simulation test provides reference for the practical project and the similar projects in the future.