Internally Statically Indeterminate Coupling between Bonded Reinforcement and Concrete

A system is internally indeterminate to the first degree only as long as all the reinforcement may be represented by one tendon. For the analysis of prestressing, tension members may be combined into one member only if they are in approximately the same location within the cross section and if they have the same prestress. On the other hand, when studying the effect of a sustained load or a constraint, including shrinkage, neighboring reinforcing bars may be combined into one tendon, regardless of the degree of prestressing.