Study the behavior of prestressed concrete deep beams using FEM simulations
Abstract
The objective of this master‘s thesis is to study and analyze the behavior of prestressedconcrete deep beams and how prestressing changes the strut and tie model.
The method used for analyzing the behavior is finite element modeling in ATENA. The strutand tie models are developed by analyzing the principal tensile and compressive stresses forthe different models at yield. The models are analyzed without prestressed reinforcement,with 25 MPa prestressed reinforcement and 100 MPa prestressed reinforcement. In orderto analyze how different load patterns affect the principal stresses, this paper analyzesthree different load patterns.
In total, two different models are analyzed, each containing three different load patterns.The models are analyzed without prestressed reinforcement, with 25 MPa and 100 MPaprestressing. The prestressed reinforcement is placed straight and curved. One of themodels is also analyzed with two openings with three different placements of the openings.
The results show a decrease in the distance between the bottom of the deep beam and thetie when adding prestressed reinforcement. A proposed equation to calculate the distancefrom the bottom of the deep beam to the tie is included in this thesis. The equationtakes both the height of the deep beam and the amount of prestressing into account. Theequation is based on the results gathered in this thesis.