基于振动响应的锚杆松弛评判方法

A Kind of Analysis Methods for Bolt Relaxation Based on Vibration Response

锚杆支护是围岩加固的一种重要形式,而锚杆的预紧力则是提高加固质量的重要的环节。但根据现行的工程应用情况,对此重要环节反倒没有引起足够的重视,从而增加了工程质量潜在事故的可能性。因此,本文针对锚杆预紧力常常不足的情况,或者当时满足,而一段时间后又因应力松驰等其他作用所再次导致预紧力不足的现象,通过在锚杆顶端与靠近锚杆处的托盘上分别安装一个同向振动的加速度传感器,利用二者之间是否发生同步振动的动力响应,即相位频谱和振动频率差,对锚杆预紧力是否满足进行快速、准确地定性判断,从而为工程质量监管提供一种可行的简便方法。

The bolt pre-tighten force is very important for bolt supporting,however it has not been paid enough attentions in present applications,ignoring it may lead to potential accidents. Generally,the pre-tighten force is often insufficient or sufficient at certain time but after a period of time insufficient again due to other effects such as stress relaxation,this paper puts forward a shortcut and accurate qualitative standard method to check the force,two acceleration senores with vibration at the same direction were installed separately on the bolt and tray,one was at the top of bolt,another was near the bolt＇s tray,then based on whether the dynamic response of vibration is the same direction,which contained phase-frequency spectrum and vibration frequency difference,a complete set of practicable and convenient detection methods have been set for the supervision of engineering quality.