Oxide Jacking of Reinforced Concrete
Application ID: 92611
Oxide jacking is the process by which reinforced concrete cracks, due to the corrosion of the reinforcing rebar rods. The corrosion process causes growth of an oxide layer on the rebar, which in turn causes internal stresses in the concrete. If the corrosion process is allowed to continue unchecked, the concrete will eventually crack, compromising the structure.
In the present model, a 2D model for oxide jacking is presented. The corrosion process is driven by oxygen reduction, and is modeled using tertiary current distribution. Oxygen diffuses from one side of the concrete block, which is assumed to have a water pore saturation of 60%. The rebar and concrete surroundings are modeled as linear elastic materials, with initial strains in each time-step based on the thickness of the oxide layer. As a simplification, only one piece of rebar is included.
Under these conditions, a crack from the rebar to the outer surface of the concrete has formed after 750 days.
This model example illustrates applications of this type that would nominally be built using the following products:
however, additional products may be required to completely define and model it. Furthermore, this example may also be defined and modeled using components from the following product combinations:
- COMSOL Multiphysics® and
- either the Geomechanics Module, or Nonlinear Structural Materials Module and
- either the MEMS Module, or Structural Mechanics Module and
- either the Battery Design Module, Corrosion Module, Electrochemistry Module, Electrodeposition Module, or Fuel Cell & Electrolyzer Module
The combination of COMSOL® products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries. Particular functionality may be common to several products. To determine the right combination of products for your modeling needs, review the Specification Chart and make use of a free evaluation license. The COMSOL Sales and Support teams are available for answering any questions you may have regarding this.