Applications of rock strength borehole probe (RSBP) in underground openings

Safe, cost-effective tunnel construction is possible when the ground is stabilized in a reasonable pace. To ensure that an optimized support system is used, detailed in-situ geological data is needed. Currently, one of the main measures to address this issue is monitoring the ground and support components (i.e. in SEM or NATM systems). However, improving ground support requires reliable data. The most common support system used in underground spaces is rock-bolt, its drillhole can be used for probing and obtaining geological data, e.g. rock strength. This paper will introduce a recently developed probe (Rock Strength Borehole Probe) designed to estimate the rock strength by scratching the borehole wall. The probe uses a micro-controller to record the data from various sensors onto a mini-SD card. RSBP applications and design considerations will be discussed in this paper, along with the results of preliminary laboratory and field tests.