FRC structural applications according to the fib model code 2010: A unified approach

In the fib Model Code 2010, fibre-reinforced concrete (FRC) is finally recognized as a cement composite material for construction: this step favours significant structural applications based on new concept requirements. In the Model Code, a strong effort has been devoted to introducing a material classification in order to standardize a performance-based production and stimulate an open market for every kind of fibre, favouring the rising of a new technological actor: the composite producer. From standard classification, the simple constitutive models introduced allow designers to identify effective design constitutive laws, trying to take into account the fibres contribution in term of performance and suitably orienting its structural use. An FRC application concerning tunnelling is discussed here, focusing on the design requirements and structural advantages offered by fibres addition and on further research needs. In this application a useful combination of strain softening and strain hardening materials allowed by the unified Model Code approach can offer designers interesting opportunities and new structural challenges.