This paper aims to determine the corrosion expansive pressure and its change rule

study the process of concrete cover cracking under corrosion expansive pressure

and improve the service life of concrete structure. Considering the concrete strain softening and concrete damage

finite element simulation and analysis of the process of concrete cracking caused by rebar corrosion and the distribution and variation of corrosion expansive pressure were carried out by changing the parameters such as cover thickness

diameter of steel bar

and concrete strength. Results show that the expansive pressure of uniform corroded steel bar was nonuniform

which was influenced by crack. The expansive pressure reached its peak before the crack penetrated the cover

then it decreased quickly

and finally remained stable. The influence of cover thickness c and bar diameter d on expansive pressure was linear

and parameters c and d could be described with a unified c/d value. Furthermore

the larger the c/d value was

the larger the expansive pressure and corrosion rate were

which means the concrete cover cracking was delayed. Finally

a simplified formula was proposed to estimate the maximum expansive pressure

and the validity and precision of the formula were validated by experimental data.