Cálculo de encofrados de gran altura mediante un Modelo de Elementos Finitos: estudio paramétrico

Eutiquio Gallego; José Mª Mª Fuentes; Álvaro Ramirez; Benjamín Navamuel; Francisco Ayuga

doi:10.3989/ic.2007.v59.i505.501

Authors

Eutiquio Gallego Dpto. de Construcción y Vías Rurales, ETS de Ingenieros Agrónomos, Madrid
José Mª Mª Fuentes Dpto. de Construcción y Vías Rurales, ETS de Ingenieros Agrónomos, Madrid
Álvaro Ramirez Dpto. de Construcción y Vías Rurales, ETS de Ingenieros Agrónomos, Madrid
Benjamín Navamuel ULMA C y E, S. Coop.
Francisco Ayuga Dpto. de Construcción y Vías Rurales, ETS de Ingenieros Agrónomos, Madrid

DOI:

https://doi.org/10.3989/ic.2007.v59.i505.501

Keywords:

fresh concrete, Finite Elements Model, implementation, formwork, parameters

Abstract

This paper deals with the estimation of the lateral pressures exerted by fresh concrete on high-height formwork surfaces by Finite Elements Models. Assuming a behaviour of the concrete similar to a fluid overestimates the pressures, particularly in higher formworks. On the other hand, equations proposed by different international standards can underestimate the pressures when a high formwork is analysed. The Finite Elements Model (FEM) developed by the authors allows a simultaneous study of the fresh concrete and the formwork as a whole. An elasto-plastic behaviour of the concrete has been considered to simulate an intermediate state between a fluid and a solid.
The implementation of a FEM requires knowing the value of some mechanical parameters of the fresh concrete. Their influence on lateral pressures against the formwork surface has been studied for every case. As a result of the parametric analyses, the Poisson’s ratio (), the coefficient of friction between the fresh concrete and the formwork () and the angle of internal friction of the fresh concrete () have been identified as the most influent parameters.

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