Narrow Results

Deformation rules and acoustic emission characteristics of granite under repeated loading-unloading are studied using the MTS Mechanics Testing System and Disp. acoustic emission instrument. It's found that the axial stiffness of granite as well as Poisson's ratio increases with the development of the plastic strain while the change trend of lateral stiffness is negative. For brittle rocks, strain is produced by three mechanisms: elastic deformation, axial micro-cracking and compaction. The peak AE rate is increasing with the plastic strain, which indicates that using the axial plastic strain as the internal damage variable to represent rock damage is reasonable.

The axial stiffness and the yield strength are the two fundamental structural parameters of a buckling restrained brace (BRB) member and can be obtained by existing design procedure. However, they are inter-related in a certain sense. This paper starts from the formulas of the axial stiffness and the yield strength, and based on the discussion on the reasonable range of geometric parameters of a BRB member, establishes the matching relationship between them.