Abstract: In Ref [1] a model of 3-D composite laminate theory was described In the present paper,based on the basic equations about 3-D linear elasticity and classicalrariational principles,by the block matrix operation and the Lagrange’s method of multipliers a series of basic equations and variational principles are obtained whichare more complere and more systematic than that in Ref [1]

Key words: magnetic field of constant intensity, flow through a rigid tube, pulsatile flow, velocity distribution, flow, composite malerials, coinposite laminate, 3-D linear elasticity, impedance