Mesoscale Approach to Modeling Concrete Subjected to Thermomechanical Loading
Concrete subjected to combined compressive stresses and temperature loading exhibits compressive strains, which are considerably greater than for concrete subjected to compressive stresses alone. This phenomenon is called transient thermal creep or load induced thermal strain and is usually modeled by macroscopic phenomenological constitutive laws which have only limited predictive capabilities. In this study a mesoscale modeling approach is proposed in which the macroscopically observed transient thermal creep results from the mismatch of thermal expansions of the mesoscale constituents. The mesostructure of concrete is idealized as a 2-D, 3-phase material consisting of aggregates, matrix, and interfacial transition zones. Nonlinear material response of the phases is described by a plasticity interface model. The mesoscale approach was applied to analyze compressed concrete specimens subjected to uniform temperature histories. Analysis results were compared to experimental results reported in the literature.
Grassl, Peter
TRT Terms: Compressive strength; Concrete structures; Cracking; Fracture mechanics; Load factor; Thermal analysis
Subject Areas: Bridges and other structures; Highways; I24: Design of Bridges and Retaining Walls; I32: Concrete;