Improved empirical hard rock pillar strength predictions using unconfined compressive strength as a proxy for brittleness

Pillars are a critical component of underground mining systems, and for this reason, pillar mechanics has historically been a major topic of rock mechanics research. In the late 20th century, many empirical studies on hard rock pillar strength were conducted, culminating in the development of a pillar strength formula by Lunder & Pakalnis( Lunder and Pakalnis, 1997) 1 based on a large database of pillar cases with different performance outcomes....