To detect the damage to reinforced concrete structure quantitatively

the moment tensor inversion theory was introduced in non-destructive testing by using acoustic emission technique.This technique was originally used for explaining the mechanism of earthquake source.The basic principle of moment-tensor-based AE technique was explained detailedly.Then the methods to detect the damage mechanism

such as crack locations

crack types and orientations of cracks

were established.The method was validated by a four-point bending test of RC beam.The moment tensor analysis of AE was conducted to identify the crack location

crack type and crack orientation of the RC beam.The results show close incidence between the moment tensor analysis and the test phenomenon.