It introduces prevention measures for common problems in construction of aluminium alloy door and window from bad integral rigidity of aluminium alloy door and window、low-protection for production and leakage of door & window,and puts forward matters need attention in construction to ensure construction quality.

Bearing capacity and security decreased due to the loss of integral rigidity of rigid frame arch bridge caused by the crack of bridge deck concrete.

Mechanics characteristics of two-way curved arch bridge reinforced by increasing its whole rigidity;

Then,the method that certain structural measure was taken to raise the whole rigidity of structure to resis.

The influences of the change of the structural global stiffness or local stiffness for pipe platform on the dynamic responses of the structure are analysed(by changing the size of structural size or the arrangement of structural members).

Technique for integrating an assembled stiffness matrix of rectangular rigid frame with side displacement;

As for the structure of axial deformation,it costed huge computation when calculating the element stiffness matrix and the assembled stiffness matrix under the global coordinate system of the structure by using the methods of coordinate change and local integration for element localization vector.