Acta Scientiarum Polonorum

The aim of the study is to compare three methods: digital image correlation, acoustic emission and method
with the application of dial sensors in analysis of crack propagation in reinforced concrete composite beam.
The elements without stirrups in the connection surface between precast and complementary concrete failed
in vivid manner while adhesion between concrete layers was lost. Beams without stirrups in the connection
area concerned in current research failed in more discrete way, because of the fact that reinforcement took
part in bearing loads causing separation of the layers. As the result there was not obtained failure of the connection
surface. The article proved usefulness of presented methods to determine the moment of connection
surface cracking and to observe other processes in the element.