Self-drilling Rock Reinforcement Systems

Rock reinforcement and ground control are key issues in

underground excavation. One scope of research,

which is in particular of interest for underground tunnelling,

are self-drilling rock reinforcement systems. In the past decades,

substantial technical advances in the development and design of

these systems have been accomplished. On the basis of some

practical examples, this manuscript illustrates the

development and successful application of self-drilling rock

reinforcement systems1 . Generally speaking, the development of

efficient self-drilling rock reinforcement systems in underground

mining and tunnelling came along with the major developments

and improvements in the field of rock drilling technology which

took place in the 70’s and 80’s of the last century. Here,

some milestones need to be pointed out. Following the successful

introduction of different types of automobile drill rigs,

one major improvement was the introduction of the first hydraulic

rock drill in 1973, allowing much higher penetration rates and

thereby making rock drilling much more efficient [1]. In the 1980’s,

different types of self-drilling hollow bar anchors have been developed

and consequently enhanced, as shown

by different patent applications dating back in these days [2, 3, 4].

In conjunction with further improvements in rock drilling technology,

self-drilling hollow bar bolts became widely

popular in the 1990’s and represent a commonly used rock

reinforcement element in modern tunnelling. In the past decade,

various other self-drilling anchors and rock bolts have been

developed both for mining and tunnelling applications.

Thereby, the same and successful installation principle using

a single-use (sacrificial) drill bit is applied.