AE monitoring of a concrete pipe for damage evaluation under cyclic loading

Deterioration of a pipeline system is normally realized by an accident of water-leakage due to damage accumulation of pipeline materials. In this study, acoustic emission (AE) method was applied to cyclic-loading tests in pipes made of asbestos-cement materials, and quantitative damage evaluation was attempted on the basis of AE parameter analysis. In the cyclic loading test, the damage of the pipe was evaluated from the relationship between the load ratio (Ratio of load at the onset of AE activity to previous load) and the calm ratio (Ratio of cumulative AE activity under unloading to that of previous maximum loading cycle). It is demonstrated that AE parameter analysis is effective for qualifying the damage levels of pipe materials.