To quantify the fracture loads of railway prestressed concrete sleepers the dynamic bending tests were carried out . In the course of tests the initial (first) crack, the crack opening and crash event of presstressed monobloc sleepers were registered by a Method of Acoustic Emission (MАE). It is shown that MAE allows to fix the beginning of cracking and evolution of cracks earlier, than other instrumental and visual inspection. During visual inspections (no longer than 5 min between the dynamic loading steps) for crack shores opening measurement the cracks are “healing”. This effect it is clearly seen by the Acoustic Emission signals movement on the next loading step. The cracs "curing" time is reduced from one load step to another. The received results will allow to define further quality of clutch of armature with concrete, and as consequence, quality of pulling together efforts of any preliminary intense reinforced concrete designs