Luchko J. Methods for evaluation of crack growth resistance and durability of ferroconcrete structural elements.

Effective methods for evaluation of the carrying ability, crack growth resistance and the stress-strain state in ferroconcrete beam elements, investigated on the basis of the concepts of a elasto-plastic fracture mechanics and ferroconcrete mechanics have been presented. Theoretical methods for determination of the boundary state characteristics for the ferroconcrete structures under short-term and long-term loading have been developed. Calculational models have been formulated and the problem of crack initiation and subcritical crack growth in non-stationary formulation has been solved. Investigations of common work of cement and reinforcement and adhesion of reinforcement connected by pipe elements have been carried out. Problems for distribution of tangential stresses between the cement and reinforcement have been solved. New models of corrosion degradation of cement and the influence of stresses on its corrosion resistance have been developed. Experimental results have been compared with theoret i cal data.