| Structural Engineering and Mechanics Volume 12, Number 6, December 2001, pages 685-698 DOI: http://dx.doi.org/10.12989/sem.2001.12.6.685 | |
Stress path adapting Strut-and-Tie models in cracked and uncracked R.C. elements | |
Fabio Biondini, Franco Bontempi and Pier Giorgio Malerba(Italy)
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| Abstract [Full Text] | |
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In this paper, a general method for the automatic search for Strut-and-Tie (S&T) models representative of possible resistant mechanisms in reinforced concrete elements is proposed. The representativeness criterion here adopted is inspired to the principle of minimum strain energy and requires the consistency of the model with a reference stress field. In particular, a highly indeterminate pin-jointed framework of a given layout is generated within the assigned geometry of the concrete element and an optimum truss is found by the minimisation of a suitable objective function. Such a function allows us to search the optimum truss according to a reference stress field deduced through a F.E.A. and assumed as representative of the given continuum. The theoretical principles and the mathematical formulation of the method are firstly explained; the search for a S&T model suitable for the design of a deep beam shows the method capability in handling the reference stress path. Finally, since the analysis may consider the structure as linear-elastic or cracked and non-linear in both the component materials, it is shown how the proposed procedure allows us to verify the possibilities of activation of the design model, oriented to the serviceability condition and deduced in the linear elastic field, by following the evolution of the resistant mechanisms in the cracked non-linear field up to the structural failure. | |
| Key Words | |
| Strut-and-Tie models; R.C. analysis and design; structural optimisation. | |
| Address | |
| Fabio Biondini, Department of Structural Engineering, Technical University of Milan, Piazza L. da Vinci 32, 20133 Milan, Italy Franco Bontempi, Department of Structural and Geotechnical Engineering, University of Rome \"La Sapienza\", Via Eudossiana 18, 00184 Rome, Italy Pier Giorgio Malerba, Department of Structural Engineering, Technical University of Milan, Piazza L. da Vinci 32, 20133 Milan, Italy | |
