松散堆积体及碎裂岩地层中锚索成孔技术研究

Drilling Methods of the Long Pre-stressesd Anchors in Talus and Broken Rock Masses

大量工程实践证实,松散堆积体及碎裂岩地层中锚索成孔难度大。潜孔锤跟管钻进工艺是在破碎、漏失、流砂等复杂地层中成孔的有效办法,但是该工艺还存在一些急需解决的问题。通过开展在松散堆积体及碎裂岩地层中进行钻孔试验,探索相关参数(给进风压、钻压、泵压等)在不同地层中的变化规律,对于完善锚索成孔工艺等具有较大的现实意义。

It is generally recognized that the difficulties in borehole advancement in the installation of pre-stressed ground anchors in talus formations and broken rock masses. The down-hole hammer with a casing immediately followed method is an effective way to advance boreholes in complicated subsurface conditions, such as, broken rock, loose soil and running sand condi tions. This paper discusses the potential difficulties of apply down hole hammer in the talus and broken rock mass formations through trial tests. The parameters such as, air entry pressure, drill bit pressure, and pump pressures, are also discussed under different subsurface conditions.