The rapid fracturing and deformation that occurs around excavations during rock bursts demand that support and reinforcement systems have both deformability and damping capabilities. The energy demand and supply approach currently used in design is considered to be too simplified to represent adequately the rock burst process and the support and reinforcement system requirements. Momentum change may be a necessary second criterion for the analysis of dynamic loading situations. At the St Ives Gold Mining Company, DE plates made from conveyor belt rubber, and dynamic cables with sliding anchors have been developed and used to improve the dynamic performance of support and reinforcement systems.
La fracturation rapide et la deformation qui se produisent autour des excavations lors de coups de terrain demandent que les systèmes d'armature et de support soient deformables et aient une capacite d'amortissement. L'approche basee sur l'energie actuellement utilisee pour la conception est consideree être trop simplificatrice pour representer adequatement les coups de terrain et les paramètres de conception des systèmes d'armature et de support requis. Le changement de quantite de mouvement pourrait être un second critère necessaire pour l'analyse des cas de charge dynamnique. St Ives Gold Mining Company a developpe et utilise des plaques « DE » constituees de caoutchouc de courroie de convoyeur et des cables dynamiques avec ancrage coulissant afin d'ameliorer la performance dynamique des systèmes d'armature et de support.
Die ploetzliche Rissbildung und Verformung, die sich in Baugruben waehrend eines Felseinbruchs ereignet, verlangt Stuetzund Verstaerkungssysteme, welche verformbare und mildernde Eigenschaften aufweisen. Die derzeitlich gebraeuchliche Methode den Entwurf auf den Energiebedarf und dessen Abdeckung zu basieren, wird als eine unannehmbare Vereinfachung betrachtet, da sie den Felseinbruch und die benoetigten Unterstuetzungs- und Verstaerkungssysteme unzulaenglich darstellt. Die Aenderung der Umstaende kann einen zweiten Ansatz fuer die Analyse der Lastsituation erforderlich machen. Die St.Ives Gold Mining Company hat DE Platten aus Foerderband-Gummi und elastischen Kabeln mit verschiebbaren Verankerung entwickelt und dazu verwendet, die dynamische Kapazitaet der Unterstuetzungs- und Verstaerkungssysteme zu verbessern.
Alleviating the rock burst hazard is important to the safe and economic operation of many underground metalliferous mines. The most commonly used approach to the design of dynamically capable support and reinforcement systems for underground rock burst conditions is based on energy considerations. In the energy approach, it is postulated that the reinforcement elements should possess yielding capability for a specified deformation velocity and displacement. This has led to an emphasis being placed on the development of yielding reinforcing elements, although attention has also been paid recently to improved surface support techniques such as sprayed liners.
In recent years, the Geotechnical Team at St Ives Gold Mining Company (SIG), Gold Fields Ltd (formerly WMC) has questioned the existing design methodology and systems. An alternative approach has been developed which is based on momentum change and emphasises the importance of the damping capability of the support and reinforcement system. As part of this effort, new products.
