TENSILE STRENGTH IMPROVEMENT OF SINGLE BOLT DOUBLE SHEARING BY VARIABLE STIFFNESS PLACEMENT

Abstract

Abstract: The variable stiffness placement along the direction of the maximum principal stress can enhance the strength of composite laminate. By focusing on the area around the hole, the optimization objective is defined as the minimization of the directional difference between the velocity vectors at the cells in the flow field and the maximum principal stress obtained by the FE. Based on this optimization objective, the optimum parameters of the flow field are calculated. Then the tape paths on the variable-stiffness ply are determined, what are consistent with the direction distribution of the maximum principal stress as far as possible. The comparative experiments of the laminates show that the average ultimate tensile strength of the variable stiffness laminates was increased. Moreover, the declining of the load bearing capability of the variable stiffness laminates is slowing when the tensile load exceeds the ultimate strength, which reduces the occurrence rate of instantaneous failure.

Key words: variable stiffness placement, single bolt double shearing joint, potential flow field, maximum principal stress direction

CLC Number:

TB332

NIU Xue-juan, YANG Tao, LI Yang. TENSILE STRENGTH IMPROVEMENT OF SINGLE BOLT DOUBLE SHEARING BY VARIABLE STIFFNESS PLACEMENT[J]. Fiber Reinforced Plastics/Composites, 2017, 0(2): 26-31.

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