Simulation of Time Dependent Degradation of Porous Materials

Foreword Porous mineral materials can be damaged by both physical and chemical attack. The presence of an aggressive solution in the pores may induce dissolution of the porous substrate and precipitation of damaging solids, cause chemical changes, or induce swelling processes, all of which lead to damaging mechanical stresses and substrate loss. These damage mechanisms can be denoted altogether as corrosion. Corrosive processes are dependent on the moisture, the temperature, and the concentration and nature of the carried species in the solution as well as on the flux rate at variable concentration and other boundary conditions. From 2002 until 2009 the DFG has financially supported our research in the field of materials science in civil engineering, which is focused on the time-dependent description and prediction of the cited damage mechanisms of porous mineral materials by using numerical simulation under real field conditions. Hereby, the modeling of microstructures and transport processes has been extensively studied. The present book holds the reports published by the involved institutes. Each report contains a summary of the main results achieved in their research. High mathematical complexity and computing cost linked to thorough knowledge of physical chemistry has been required for the successful achievement of the research goals. Indeed, the implemented numerical models and simulation programs, some of which are in ongoing development, provide for an increasingly useful tool to predict the described corrosive processes in engineering and underground constructions as well as in historic buildings.