Background: The reactor structure may be destroyed by steam explosion
which could cause serious accident.Purpose: To evaluate the damage caused by the steam explosion outside the reactor.Methods: The method to evaluate the structural response of reactor cavity is established.Firstly
the flexural capacity and shear resistance are assessed.Secondly
based on the elastic-plastic FEM established in this paper
the dynamical response under different soil stiffness is analyzed.Results: The time displacement curve of the reactor structure is obtained.Conclusions: The structural integrality could be estimated and the possibility of leak accident can be judged.