Johannes Rathgen

Johannes Rathgen, M.Sc.

Fachgebiet Massivbau

Beethovenstraße 52

38106 Braunschweig

Telephone: 0531/391-5576

Research project:

Structural safety of existing concrete structures

Existing structures such as concrete bridges are subject to mechanical degradation processes during their service life. In combination with the inherent deficits of the structure, the degradation processes lead to noticeable changes in the structure (damages). In addition, increased operating stresses may occur that an assessment of the structural safety (residual load capacity and advance notice behaviour) is required when the increased operating stresses is combined with the damage. This assessment should be as accurate as possible. In a completed PhD project within the Graduate School 2075, approaches for the evaluation of the residual load-bearing capacity of concrete components under consideration of mechanical degradation were developed. Based on this, the structural safety of existing structures has to be investigated.

The aim of this PhD project is the development of a method of evaluation for the structural safety of aged reinforced and prestressed concrete structures. On this purpose, the residual load-bearing capacity at structural level (system level) will be investigated conceding theoretical and numerical investigations and by taking different degrees of damage (damaged subsystems) with special consideration of system influences (stress redistributions, existing load-bearing mechanisms, etc.) into account. Based on this, an analysis of the failure announcement will be established by comparing the residual capacities of different degrees of damage. Finally, different structural systems and damage scenarios will be investigated and evaluated using the developed method.