Numerical modeling of biogenic sulphide corrosion in concrete sewer pipes

In order for concrete sewer pipes to properly fulfil their function, the load bearing capacity should be sufficient to withstand the loads experienced during operation. Sulphuric acid produced by the bacteria present in the sewer system may deteriorate the concrete pipe significantly, thereby affecting the load bearing capacity. This study presents a first step in the development of a numerical model for describing the chemical degradation processes in sewer pipes, which is done by coupling the diffusion processes of chemical omponents to a continuum damage model that mimics the resulting degradation. The model should be able to provide useful guidelines regarding the durability of concrete sewer pipes in engineering applications. The main results of a literature study on the chemical processes in concrete sewer pipes are presented, followed by an analysis of a basic two-dimensional benchmark problem in which three (diffusion-)reaction models are coupled to an isotropic damage formulation to simulate the chemical deterioration processes of a sewer system