Numerical analysis of the post-tensioning Anchorage region of a prestressed beam

The post-tensioning technique, widely known in the prestressed concrete industry, consists of inducing a generalized state of compressive stresses into a structural element, which is prestressed through the application of an external force onto a steel cable embedded in concrete, anchored on the edges of the structural element. Based on this simple idea, researchers have developed different simplified methods of design which have been used for structural engineers worldwide. However, these methods seem to be inefficient in some cases to evaluate the distribution of stresses at the local scale: This is the case of the extreme anchorage zone in post-tensioned beams during construction, in which the high concentration of effects induces cracks into the concrete. The aim of this paper is to study the linear and non linear mechanical behavior on this region using a tridimensional finite element model, analyzing the different fields of stresses in the post-tensioned beam edge and comparing the distribution of effects predicted by the standard construction codes and those obtained from the finite element simulations.