Sensitivity of micro-buckling to 2D and 3D fiber-misalignment

BARULICH, NESTOR DARÍO; GODOY, LUIS AUGUSTO; BARBERO, EVER JOSÉ

Buenos Aires

Congreso; COMAT 2015 6th International Conference on Science and Technology of Composite Materials; 2015

Facultad de ingeniería, Universidad de Buenos Aires

This paper focuses on computational modeling of sensitivity of micro-buckling to imperfection type by including geometric imperfections together with kinematically non-linear behavior for a unit cell domain. Two types of defects are considered for the fiber: one with a helicoidal shape, identified as 3D defect, and another with a sinusoidal plane shape (2D). Both defect models have a maximum misalignment angle of the fiber with respect to the ideal or perfect configuration, as is usually considered in fiber micro-buckling problems. A total of 112 cases were computed; in terms of defect type, volume fraction, arrangement, angle for 2D models and misalignment angle. Homogenization was carried out to obtain macroscopic stress tensor, in which the unit cell has a square or a hexagonal cross section. The results indicate a high imperfection-sensitivity for small misalignment angles. The type of defect and fiber arrangement do not have a large influence on the results.