Title: Reversible Creep of Building Materials under Constant and Repeated Loading
Author(s): M.M. Lordkipanidze, L.I. Minkin, and N.K.Chakhvashvili
Publication: Symposium Paper
Appears on pages(s): 77.1-77.6
Keywords: bond rupture, creep, dislocation model, loading, micro-crack, Rebinder’s effect
The results obtained for various materials in liquid surface-active media (SAM) showed that the limit deformation of reversible creep is achieved under cyclic loading many times faster than under constant loading. The only exception is steel in the gaseous hydrogen medium. This suggests an idea that the phase state of a SAM plays the decisive role. The kinetics of the growth of pre-critical Griffith micro cracks is provided by the joint action of mechanical stress and a surface-active medium and is determined by the velocity with which a surface-active medium moves to the crack vertex via fine channels.
An important feature of the phenomenon of reversible creep of solid bodies in SAM is the complete reversibility of creep independently of the number of cycles of placing the specimen in the SAM which is subsequently removed. The specimen’s properties remain constant: in the absence of the SAM, the elastic deformation value does not change and in the presence of the SAM the reversible creep parameters also remain constant.
The phenomenon of reversible creep of solid bodies under the SAM action is a unique tool of investigation of the formation and growth of pre-critical cracks in stressed materials. Further investigation of this phenomenon can facilitate the understanding of the nature and mechanism of catastrophic failures of stressed structures.