Numerical Modelling for Shear Strength Evaluation of a High Performance Fibre Reinforced Concrete Beam According to fib Model Code 2010 Guidelines
Rodolfo Giacomim Mendes de Andrade1; Magno Teixeira Mota1; Michèle Schubert Pfeil1; Romildo Dias Toledo Filho1; Ronaldo Carvalho Battista1; Eduardo de Moraes Rego Fairbairn1
1 COPPE - UFRJ
doi:10.20906/CPS/CILAMCE2017-0627
Resumo
For scenarios where a structure is more susceptible to fail in shear instead of bending and presents a high ratio of transverse reinforcement, dispersed steel fibre reinforcement is found to contribute not only to shear strength but to post-cracking behaviour. A proposed cross-section of a High Performance Fibre Reinforced Concrete (HPFRC) beam fits this scenario due to its slender web thickness. The evaluation of the design shear strength can be performed by either analytical procedures or numerical procedures via nonlinear finite element analyses. The new fib Model Code 2010 presents a calculation method divided into four levels of approximation - levels I to III, to be performed by analytical procedures, and level IV, by numerical procedures - whereas their complexity rises with the calculation accuracy, as well as shear strength. This paper describes the calculations of all four levels of approximation, especially the fourth, in which nonlinear finite element analyses were aided by DIANA FEA BV software. As expected, for the proposed cross-section a gradual increase in shear strength capacity was observed for each Level of Approximation, emphasizing that the simplest level can be very conservative whilst the last can provide considerably higher strength values when compared to analytical methods.
Palavras-chave: HPFRC; Shear strength; Nonlinear finite element analysis