The elasticity theory of dislocation of cubic quasi crystal is developed, and analytical expressions of displacement and stress fields for screw dislocation in cubic quasi crystal are obtained by using governing equations of anti plane elasticity problem of the quasi crystal.

This paper discusses method to find special solution of elastic plane problem is worth for practical purpose.

Then, based on the analysis for the expression and multivalue property of the doubly-periodic analytic function (the real part of which is given) and its object function, the general expression of the two complex potentials in plane elasticity for a body with a dou.

In regard of the problems on semi plane, when the calculation of its numerical value proceeds, the calculation accuracy will come under influence if the effectiveness of the infinite far place on the nearby sites are not considered.

This paper, utilizing Flamant formula, has deducted a formula of settlement computation for a semi-infinite planar elastic body acted by trapezoide distribution load and given a method of calculatiy the settlement of semi-infinite planar elastic body acted by arbitary distribution aoad.