Variational principles and generalized variational principles on flow theory of plasticity;

On the generalized variational principle of viscoelastic beam columns with damage;

Application of generalized variational principle to calculation of additional expansion and contraction forces of CWR on bridge;

The generalized variational principles for rigid-body-fluid interaction problems are presented,and the rigid-body are thought to be linked by elastic elements each other.

For the dynamic coupling problem, variational principles of minimal potential energy, generalized variational principles and complete generalized variational principles of three variables are built and they are strictly proved.

From Maxwell s equations in electromagnetic field theory and by the method of variation integral, a group of variational principles and generalized variational principles are built for the initial value problems of electromagnetic field theory.

Based on the generalized variation principles and the bi-stable characteristics of a post-buckling beam,the nonlinear relationship between the transversal force and displacement is deduced by considering the effects of axial compression on the beam length constraint.

Based on the generalized variation principle and the complex solution of plane problems, an analytical_numerical scheme is developed to solve the soil pressure on an arbitrarily displaced retaining wall.

With the one dimensional plane wave theory,the expression of load on the structural periphery is developed,and the generalized variation principle for the dynamic analysis of undergrou.