Nonlinear analysis of containment structure based on modified tendon model

Abstract

This paper proposes a modified stress–strain relation for bonded internal tendon in containment structures on the basis of the tension stiffening effect and the bond characteristics between a tendon and its surrounding concrete. Differently from general approaches for the consideration of bond-slip, which take the double nodes in defining the displacement field, the proposed model indirectly considers the bond-slip effect through the modification for the stress–strain relation of tendon. Since the proposed tendon model takes into account the bond-slip effect without taking double nodes in the numerical modeling of containment structures, it can effectively be implemented into commercialized programs which have a lot of limitation in considering the bond-slip effect at large complex containment structures. The solution algorithm for an un-bonded internal tendon whose structural response is not section-dependent but member-dependent is also introduced. The different structural responses from those in bonded tendon are evaluated by successive iterations and finally considered by the additional modification for the stress–strain relation of tendon. The validity of the proposed tendon model is verified through correlation studies between analytical and experimental results for PSC beams and 1/4 PCCV containment structures.