As part of a previously completed research project (Project No. 82/95), minimum reinforcement requirements for reinforced concrete were investigated and presented in a technical position paper. A model used for the investigation of the deformation capacity of structural concrete - the Tension Chord Model - was further developed to deal with crack development and minimum reinforcement requirements. This allowed for a consistent comparison of the minimum reinforcement requirements specified in different design norms (SIA 162, ENV 1992-1, and ENV 1992-2) and the formulation of the current project's research requirements.
The objective of the current project is to broaden the use of the Tension Chord Model to include prestressed concrete elements and design applications.
Updated Tension Chord Model which includes prestressed concrete elements.
Theoretical model used for deformation capacity considerations is extended to treat problems of crack formation and minimum reinforcement. Assuming a rigid perfectly plastic bond stress slip relationship the behavior of reinforced and prestressed concrete members subjected to loads and external and internal restraints is analysed.
The presentation of the tension chord model and the different code requirements is supplemented by remarks on bond behaviour, on the assumption of the concrete cross-section, on the concrete tensile stength needed in tension chord model calculations, and on the question of permisssible crack widths.