An analysis model is proposed for evaluate rigid evolution of displacement jump in elastoplastic solid

which based on displacement jump condition and a specific single freedom degree dynamic system

i.e. condition of displacement jump is educed with strength theory of materials; after displacement jump occurs

the part of free movement is taken as a rigid body; and evolution of displacement jump depends on the stiffness of jump joint (or called interface)

friction law of rate and state dependent

input loading and other parameters of the dynamic system. An example of frictional solid is given to illuminate the model how to work

in which the transformation of static to dynamic and loosing of material cohesion as input are stated especially.