Abstract：in order to meet the aircraft stiffness requirments of the typical rectagular fuselage with large opening, a design scheme of adding four side beams to the groove large opening structure to strengthen the stiffness was designed and its engineering analysis model is constructed. The bending stiffness and torsional stiffness are compared with the typical rectagular fuselage without openings.The stiffness ratio of the two kinds of configuration are obtained, and then the formula for sectional area of side beams are given under a certain stiffness index. Besides, the curves of stiffness ratio with area of side beams and the stiffness strengthen process for rectangular fuselage with large opening are also shown. This study can be used in the scheme phase of the large opening structure plane strengthen design.
2022, Vol. 43 
