An Investigation of Square Delamination Effects on the Buckling Behavior of Laminated Composite Plates with a Square Hole by using Three-dimensional FEM Analysis

Abstract

In the present study, the effects of the square delamination, around a square hole, on the buckling loads of the simply supported and clamped woven steel-reinforced thermoplastic (LDPE, F.2.12) laminated composite plates have been investigated. Three-dimensional finite element models of laminated plates with four layers have been established. The square delaminations exist between second/third layers. The stacking sequences are chosen as [0]4, [15 / 15]s, [15 / 15]2, [30 / 30]s, [30 / 30]2, [45]4. Firstly the harmony between theoretical and finite element solution results of the plate without hole and delamination has been shown. Then, the buckling loads have been determined for each of the models having different square delamination dimensions. Significant decreases in the buckling loads occur after a certain value of delamination dimension. It is seen, for clamped plates that the changing ratios of the results of the symmetric or antisymmetric cases are approximately the same and there is a linear relationship between the values of the fiber angles and buckling loads.

Experimental and Numerical Buckling Analysis of Delaminated Hybrid Composite Beam Structures

“…By decreasing the H/t ratio the critical buckling resistance load decreases for all non-hybrid and hybrid laminated composite beams. 4 indicates that global buckling mode occurs for the defect position of H/t = 0.5, as well as mixed buckling mode for defect position of H/t = 0.25, and local buckling mode for defect position of H/t = 0.125 (see Fig. 8).…”

“…The delaminated composite beams of [G 90 4 were manufactured from the unidirectional GFRP and CFRP composites. The thickness of all laminated beams was 2 mm.…”

“…It can occur in several ways during manufacturing process, maintenance and impacts of foreign objects [2,3]. Laminated composite materials containing one or more delamination can buckle at a lower level of compressive load than laminated composites without delamination, and this level depends on the size, position and shape of the delamination [4].…”

“…In the present study, the effect of delamination position on the critical buckling load of non-hybrid and hybrid composite laminates of CFRP and GFRP with single delamination position is studied. 4 were chosen to compare the buckling resistance of hybrid and non-hybrid composite beams. The delaminated composite beams were manufactured and tested to find the critical buckling load.…”

“…Experimental and numerical studies are carried out to determine the buckling load of delaminated composite beams. The laminated composite beams with various laminate designs of [G 90 4 were manufactured and tested to find the critical buckling load. Three different defect positions were placed through the thickness to find three main buckling modes.…”