Engineering approach to nonlinear analysis of concrete structures

The objective of this paper is to explore the potential of the lumped-plasticity program STRUPL-1C and to illustrate its use as a practical engineering tool for the nonlinear analysis of concrete structures. This result is achieved through the development of a moment-rotation constitutive law that uses realistic material laws and is valid for any reinforced, prestressed and partially prestressed concrete planar frame at all behavioral states along the loading history. The effects of the main parameters that influence the moment-rotation relationship are investigated and discussed. Finally, the developed constitutive law is applied to the nonlinear analysis of a few reinforced and prestressed concrete continuous beams. Comparison to both experimental tests and more-complex nonlinear analysis techniques proves the accuracy of solutions obtained by the STRUPL-1C computer program. The examples reported also prove that the proposed approach enables considerable simplification of the structural model required for a historical nonlinear analysis of concrete structures and demonstrate the high potential of the approach with respect to its use in engineering practice. © ASCE.