Based on the finite cover techniques of manifold method

the displacement function of bolt was determined according to the cover system of manifold element; and the numerical manifold model of fully-grouted bolt was established; and the concept of bolt manifold element as well as its numerical calculation form were obtained. This model meets the physical meaning of fully-grouted condition; it is a numerical method of bolt with feature of partial analysis and better calculation accuracy. At the same time

bolt and mathematics cover are relatively independent

only the bolt is required to be in mathematics grid

while no have strict requirement of their relative location has to be met

so general grid can meet complex configuration of bolt. This model can be used in simulating geotechnical bolt and analyzing the interaction of reinforcing bar and concrete.