A guideline for tendon support design

CIM Bulletin, Vol. 88, No. 990, 1995

Brian O'Hearn, Mine Safety Division, Northwest Territories Department of Safety and Public Services, and Doug Hanson, Douglyn Enterprises, Inc., Alberta Canada

The most commonly used tendon supports in the Sudbury area include rock bolts, rebars, friction anchors and cable bolts. Due to the fact that these tendons are physically different and employ different anchoring systems they offer varying degrees of stiffness, yield ability, load capacity, anchor dependability and energy absorption. These differences coupled with variable rock mass and changing stress conditions have made it challenging to engineer the design of an effective support system. By tapping into the knowledge and experience gained by ground control practitioners, an empirically based rating system has been assembled that offers a guide to designers of support systems when choosing the most effective tendon support over a range of rock mass and stress conditions. A methodology referred to as support planning can be used to design support systems whose rehabilitation costs will be minimised. The use of multiple tendon types in any one support layout is advocated, particularly when the stress state of the rock mass to be supported is expected to undergo a change.
Keywords: Rock mechanics, Support systems, Rock mass characteristics.