Based on the small-deflection elastic theory and some simplified assumptions, the initial stiffness,the slack stiffness and the critical slack load have been derived theoretically.

Discussion on bending rigidity anisotropy of fabrics;

Bending deformation and bending rigidity of mechanical components;

Approach to calculating bending rigidity of rubber-reinforced track of tractors and its experimental verification;

Applied investigation on the effects of bending stiffness of machine bed's simulating parts on its thermal geometrical precision;

Analysing parameters of bending stiffness of FRP and designing its structure;

Engineering algorithm on bending stiffness of elastic rubber bushing of car suspension;

The mechanical models of bend stiffness and bend strength of the pallets girder and deck were established.

The relationship between axial stiffness, torsional stiffness, flexural stiffness and deformation has been given.

Based on the bifurcation buckling of abnormal beamcolumn steel frame,it was found that the way to ascertain column s effective length of normal steel frame can also be used in abnormal beam-column steel frame;the principle of virtual work was used to deduce the flexural stiffness of two kinds of Abnormal beams,and its effect on the effective length of rigid steel frame column was analyzed.