Transient nonlinear thermomechanical modelling of a steel ladle

• The behaviour of Equivalent Continuous Media of masonries with and without mortar, that considers the joint state, the brick creep and the temperature dependence, were built using a homogenisation approach. • A thermomechanical finite element model of a steel ladle was created, considering the three first thermal cycles, replacing the refractory masonries by the Equivalent Continuous Media identified previously. • The influence of joint behaviour, joint thickness and brick behaviour was studied. • The simulation has shown the importance of the joint thickness and the material creep on the decrease of stresses in the steel shell. To improve the design and the lifetime of steel ladles in steel industry, a finite element thermomechanical model can be useful. The working layer, in contact with the molten steel (1650°C) is often made of a refractory masonry without mortar. Gaps between bricks (called dry joints) play an important role, decreasing the stresses in the structure. To consider these joints in a numerical model, it is proposed to model the masonry structure (set of bricks and joints) by a continuous medium following a dedicated set of governing equations. This continuous medium must take into account the joint state (open or closed), the masonry orthotropic behaviour and the nonlinear brick behaviour (elastic-viscoplastic) at high temperature leading to creep. A material behaviour law was built with these different aspects, especially for secondary creep. This law was used to represent the working lining masonry in a finite element model of a simplified steel ladle. It allows the quantification of the influence of the joint thickness and their behaviour, and the impact of creep.