Chloride initiation can be approximated by Ficks law. First crack depends on the rate of formation of rust. Rust formation may be modeled by Liu and Weyers law. Cracking models are review in "Modeling of corrosion-induced concrete cover cracking: A critical analysis"

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Many empirical relations are available in literature. You can search papers authored by Kapilesh Bhargava (about 5 papers) to start with and find cross references in them. That was empirical.

If you want to go analytical, there are papers by Josko Ozbolt (there on research gate) which deal with modeling the ingress of ions towards the reinforcement in concrete by solving diffusion equations applicable to concrete environment. The effects of corrosion process on the consequent cracking are well captured in those studies. 

Hello There

Many empirical relations are available in literature. You can search papers authored by Kapilesh Bhargava (about 5 papers) to start with and find cross references in them. That was empirical.

If you want to go analytical, there are papers by Josko Ozbolt (there on research gate) which deal with modeling the ingress of ions towards the reinforcement in concrete by solving diffusion equations applicable to concrete environment. The effects of corrosion process on the consequent cracking are well captured in those studies. 

You can review the PhD dissertation by Chin-Wei Lee entitled "Simulations of long-term bridge deck deterioration due to corrosion" (2011) at the University of Wisconsin-Milwaukee. It address chloride penetration, crack formation and delamination of concrete.