Assessment of the influence of gravity load in RC beams’ critical zones subjected to cyclic loading

Assessment of the influence of gravity load in RC beams’ critical zones subjected to cyclic loading, Gião, Rita, Lúcio Valter, and Chastre Carlos , Proceedings of the fib Symposium 2019: Concrete - Innovations in Materials, Design and Structures, May, 27-29, 2019, Kraków, Poland, p.497-504, (2019) copy at

Date Presented:

May, 27-29, 2019


The aim of the present paper is to evaluate the gravity loads effect in the behaviour of reinforced concrete beams critical zones subjected to cyclic loads. A numerical study to assess the influence of gravity load on RC beam critical zones subjected to cyclic loading is presented, assuming the level of gravity load as a variable parameter. For this purpose, the non-linear model was previously validated with an experimental campaign carried out on RC beam connection subject to cyclic loading with and without gravity loads. The consideration of the gravity load effects led to an accumulation of negative (hogging) deformation and the formation of an unidirectional plastic hinge. In order to validate this behaviour in an overall structural response, a non-linear numerical analysis of a RC frame system under cyclic loads, subject to different levels of gravity load, is also presented. The numerical results are analysed in terms of global hysterical response, accumulated energy dissipation and equivalent viscous damping ratio. In this numerical study was observed that the hysteretic response depends on the load path. In the presence of higher gravity loads levels, the structure hysteretic behaviour exhibits higher damage levels and the failure mechanism is prone to the formation of four plastic hinges. This phenomenon is analysed and discuss in the present paper. © Federation Internationale du Beton (fib) - International Federation for Structural Concrete, 2019.


1. (1994) Behaviour and Analysis of Reinforced Concrete Structures under Alternate Actions Inducing Inelastic Response, CEB Bulletin D’Information Nº. 220 Frame Members;
2. Chopra, A.K., (2001) Dynamics of Structures: Theory and Applications to Earthquake Engineering, , Englewood Cliffs, NJ, Prentice-Hall; 3. Dhakal, R.P., Fenwick, R.C., Detailing of Plastic Hinges in Seismic Design of Concrete structures (2008) ACI Structural Journal, 105-106, pp. 740-749;
4. (2004) Eurocode 8 - Design of Structures for Earthquake Resistance. Part 1: General Rules, Seismic Actions and Rules for Buildings EN 1998-1;
5. (2003) Seismic Assessment and Retrofit of Reinforced Concrete Buildings (State-of-Art Report Prepared by Former TG7.1); fib Bulletin Nº. 24 Fédération Internationale du Béton (fib), Lausanne, Switzerland;
6. Gião, A.R., Lúcio, V., Chastre, C., Assessing the Behaviour of RC Beams subject to significant gravity loads under cyclic loads (2014) Engineering Structures, 59, pp. 512-521;
7. Mazzoni, S., Mckenna, F., Scott, M.H., Fenves, G.L., (2006) Opensees: Open System for Earthquake Engineering Simulation, ,,;
8. (2004) New Zealand Standard: Structural Design Actions. Part 5: Earthquake Actions, , NZS 1170.5 New Zealand

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