Examination of rock reinforcement and stability of the hard rock pillars due to the over-break and blast damage

The focus of this study is to identify and understand the behavior of the designed pillars and rock reinforcement in hard rock. The analysis is based on the observations during construction of the new underground bus terminal Slussen, blasted underneath the Katarina Mountain, in the City of Stockholm. A two-dimensional, linear elastic-plastic, finite element model (RS2) is created, and numerical analysis was conducted to investigate the stress concentration in the pillars, yield zones and maximal reduction of the pillar area to retain pillar stability.