## THERMAL SCIENCE

International Scientific Journal

### ON INTERNAL STABILITY LOSS OF A ROW UNIDIRECTED PERIODICALLY LOCATED FIBERS IN THE VISCO-ELASTIC MATRIX

**ABSTRACT**

In the present paper, the microbuckling or internal stability loss in the viscoelastic composites containing unidirected fibers under compression along the fibers is studied by use of piecewise homogeneous body model. In this model, it is used the Three-Dimensional Geometrically Nonlinear Exact Equations of Viscoelasticity Theory. The composite material was considered as an infinite viscoelastic body with a row unidirected periodically located elastic fibers that have an initial infinitesimal imperfection. When the initial imperfection starts to increase and becomes indefinitely, this is taken as a stability loss criterion and co-phase microbuckling mode out of plane are taken into account. The numerical results about the influence of the interaction between the fibers on the values of the critical time are abtained and presented.

**KEYWORDS**

PAPER SUBMITTED: 2018-11-28

PAPER REVISED: 2018-12-26

PAPER ACCEPTED: 2019-01-15

PUBLISHED ONLINE: 2019-03-09

**THERMAL SCIENCE** YEAR

**2019**, VOLUME

**23**, ISSUE

**Supplement 1**, PAGES [S427 - S438]

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