Proposal of poro-mechanical coupling among ASR, corrosion and frost action for damage assessment of structural concrete with water

摘要

Concrete durability related events have similar processes in terms of crack initiation and its propagation such as alkali silica reaction (ASR), freeze-thaw cycles (FTC) and steel corrosion. All of them will create additional liquid/solid pore substances and finally lead to volumetric expansion and subsequent cracking in concrete composites. This paper builds a platform of triple poro-mechanical coupling model for micro and meso-scale events of ASR, FTC and steel corrosion in consideration of the mutually interacting processes. The proposed model attempts to cover the most essential aspects, from thermo-chemo coupling at micro-scale to the poro-mechanical coupling at meso-scale, and finally leads to the coupled fracture of structural concrete at macro scale. Several simulation examples are presented for both single and coupled deteriorations of structural concrete, and it is clarified that the combined deformation and damage of concrete are not the simple compilation of each sole effect, but it is highly path-dependent on both crack patterns and deformation levels. This triple coupling model can provide a platform, on which the coupled complex damages to structural concrete are consistently dealt with for damage assessment of structural concrete.