Zur Innenverankerung von Spanngliedern unter Beruecksichtigung nichtlinearer Materialgesetze fuer Beton und Betonstahl

The state of stress and strain near tendon - anchorage - assemblies which are placed in plane parts and within the span of prestressed structural members is analysed assuming linear and non-linear constitutive laws. Especially the resulting tensile force at the rear of the tendon - anchorage - assembly is considered. The linear elastic analysis and well known experimental results show that the prestressing force causing cracks at the rear of the tendon - anchorage - assembly can be calculated by simple formulas based on equilibrium. For that only the definition of a special anchorage area depending on the use tendon -anchorage - assembly is necessary. The connection between the rear of the tendon - anchorage - assembly and the concrete should be assumed to be able to transfer tensile stresses. The non-linear analysis describes the structural behaviour near tendon - anchorage - assemblies realistically and the resulting tensile force after cracking at the rear of the tendon - anchorage - assembly can be determined depending on the prestressing force and several other parameters. For example it is revealed that the influence of an existing concrete pressure in the direction of the prestressing force cannot be taken into account according to the rules in the German DIN 4227. Based on the results of the non-linear analysis a simple mechanical model consisting of two bars with a spring between them is developed. It can simply be used in practice. (orig.)Available from TIB Hannover: RR 275(1996,1) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman