NotePrediction of early age curling in thin concrete topping over wood floor systems

Abstract

This paper presents finite element simulations of curling of unreinforced concrete topping laid over wood floor systems. The finite analysis consists of two parts. The first part calculates the relative moisture distribution with respect to the age of the concrete, while the second determines the topping curling deformation based on modulus of elasticity, density, and shrinkage of the concrete. With the finite element model the curling profile at any point in time can be predicted. Predictions agree reasonably well with measurements from a full-sized wood floor with a thin concrete topping. A model-based parametric study was performed. For the floor size investigated the results of the parametric study indicate that curling is greatly influenced by topping thickness and relative humidity of the surrounding air. Although the modelling as discussed is a preliminary approach, it provides a basis for further enhancements that will address factors such as creep and relaxation of concrete and deformation of the underlying floor system. Key words: finite element analysis, concrete topping, wood floor, curling, shrinkage.