@MASTERSTHESIS{ 2021:854099111,
 	title = {Chemical and creep models applied for concrete Affected by alkali-aggregate reaction.},
 	year = {2021},
 	url = "http://tede2.unicap.br:8080/handle/tede/1952",
 	abstract = "Concrete structures suffering from Alkali Aggregate Reaction (AAR) are also affected by other deleterious mechanisms such as creep and shrinkage. In Brazil and many other countries worldwide, numerous cases of building foundations and concrete dams were investigated due to the damage associated to AAR. Macroscopic AAR models must have to consider the influence of the main environmental parameters, such as temperature, saturation degree and the speed of the evolution of the chemical reaction. To be relevant in structural applications, concrete creep models have to consider several important phenomena, such as non-linearity, multi-axiality, thermal and drying effects. In order to prevent those pathologies, plan rehabilitation works or create new design procedures, the numerical simülation through finite elements method (FEM) is recognized as a very useful tool. The aim of this work is to implement a chemical model to simulate the advancement of the reaction and a mechanical model to simulate creep and shrinkage phenomena in COMSOL Multiphysics®, as a way to reassess concrete structures suffering from those mechanisms. The model to represent the AAR was developed by Morenon (2017) and the creep and shrinkage models were developed by Sellier et al. (2016), currently in use on other commercial softwares like CAST3M and Code_Aster. The models were implemented in COMSOL separately in order to evaluate their responses, comparing to theoretical results and experimental benchmarks proposed by the developers of such models. The chemical model to reproduce AAR was compared to the theoretical results shown by the developer of the model (Morenon, 2017), and the creep model was compared to experimental data regarding creep strains in different directions of a specimen under various loads and different temperatures. The results of the simulations were in reasonable good agreements with the results taken from the literature, with a maximum error of 10%, showing that the implementation in COMSOL was a success. Although, the shrinkage model didn't show any good results, and some numerical instability was encountered when the coupling of such models was done, and to fully reproduce a concrete structure affected by those deleterious phenomena, a coupled chemo-mechanical-damage model in a rheological framework must be implemented, which will be the aim of the next research projects.",
 	publisher = {Universidade Católica de Pernambuco},
 	scholl = {Mestrado em Engenharia Civil},
 	note = {Departamento de Pós-Graduação}
}