An Integrated Computational System of Mass/Energy Generation, Transport and Mechanics of Materials and Structures

Abstract

The authors present an integrated computational system consisting of a 3D FE structural analysis program and a 3D FE thermo-hygro physical analysis system which can model the development and deterioration of concrete materials performance. The thermo-dynamic process provides solutions for temperature, pore pressure, pore distributions, and other material properties in both 3D space and time. By passing this information to the structural mechanics process, the stress and damage to RC members caused by temperature changes and shrinkage can be obtained. The generation of cracks changes the material properties of mass transport, which are controlled by thermo-physics. This proposed integrated system can be used for the simultaneous evaluation of overall structural and material performances without distinguishing between structure and durability.

Modeling of Calcium Leaching from Cement Hydrates Coupled with Micro-Pore Formation

“…The third term of the equation represents the diverging mass flux. The calcium ion flux at a specific boundary surface is expressed by, (Ishida and Maekawa 2000).…”

“…By considering both diffusion and advection (Ishida and Maekawa 2000), the flux of calcium ions transported in a porous media is written as (see Fig. 2),…”

“…By treating the capillary and gel pores in the cement paste as ion transport pathways, the porosity, φ, is expressed by the following equation (Ishida and Maekawa 2000):…”

Modeling of structural performances under coupled environmental and weather actions

“…Recently, in addition to the above modeling related to early age development phenomenon, the authors have been widening the application of DuCOM in order to cover the deterioration and resolution of cementitious materials and steel corrosion under long-term environmental actions [10,11]. For that purpose, concentrations of chloride ion, oxide, and carbon dioxide were added to the thermo-hygro system, as the additional degrees of freedom to be solved (Fig.…”

“…In this paper, coupling with oxygen transport model, this phenomenon can be simulated. The detailed discussion on the formulations of the oxygen is omitted for lack of space, since they are almost same as those of carbon dioxide [10]. Finally, using the Faraday's law, electric current of corrosion is converted to the rate of steel corrosion.…”